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All devices on the network can be connected to each other through the Internet of Things. The Internet of Things is slowly evolving into the next stage of the Internet world. At the same time, the need for people to use the Internet of Things is increasing day by day. This enables IT devises to work automatically without any human intervention by sending information, which we know as robotic devices. Automating objects makes them smarter. From smart cities to health centers, agricultural systems, logistics and small businesses, education, government, even smart daily life and smart environments are going to be made possible by IoT. Although technologies have evolved in recent years, there is a need for more observation and human awareness as improvements are made. Since IoT has evolved through a lot of technology and research, it is only natural that challenges arise. By Kevin Ashton, IoT was first proposed in 1999. IoT devices are used throughout our lives. And it is very important in various studies of computer science. In this way, it has taken a leading place in the world of research today. IoT was used during the Covid 19 epidemic for contact tracing.
Internet networks can keep the human world connected to information. The Internet can easily operate IoT related objects such as various degrees of processing, actuation capabilities, and sensing devices because these objects are connected to each other through the Internet and can communicate data. So from this, we can say that the main reason for the use of the Internet of Things (IoT) is that different objects, from different places, at different times, to do the same thing, or to do different things can be used very easily, single network or internet connection. The Internet of Things is slowly being considered the next stage in the evolution of the Internet. In the future, IoT will achieve countless goals by integrating many common devices through the Internet. The number of devices that could be part of IoT is now as low as 0.6%. But by 2022, about 60 billion devices will probably be connected to the Internet. As the days go by, IoT devices and with it the Internet, become an integral part of our lives. By using quantum and nanotechnology, we have been able to control storage, processing speed, and sense. Smartphone, automobiles, systems, cameras, toys, cars, and home appliances can all communicate with each other through the Internet and the Internet of Things, and we can call it the Smart City.
IoT plays an important role in improving the smartness of cities and improving general infrastructure. IoT needs some sophisticated applications to make any city a smart city parts of the city, taking appropriate action before natural disasters, as well as monitoring the physical condition of bridges and buildings.
Different Install sound monitoring devices in places, such as hospital school courts etc. As well as monitoring the movement of pedestrians and vehicles. Artificial intelligence (AI) enabled IoT applications are being utilized in these smart cities. To keep the environment clean, IoT applications are used to install weather-adapted street lights and identify environmental waste. Large highways have been alerted by this IoT to provide alert messages and important information, and alerts can also be made easily depending on the weather conditions or the dangers such as traffic jams and accidents. Some of its advanced applications are Aware Home and Smart Santander functionality. Some big cities have plans on how to apply the Internet of Things to most systems, from their parking meters, streetlights, sewerage gates, all set to connect to the Internet. .This kind of applications will make significant progress in saving both money and energy.
All smart roads use IoT sensors and IoT technologies that make driving easy and safe. It provides drivers with real-time information about the weather and road conditions. Warns drivers about finding parking spaces and incoming traffic. This helps to prevent accidents. These technologies are especially helpful on mountain roads. Landslides are a common occurrence in the mountains. Roads that have car charging capabilities can also charge their electric vehicles with the help of electromagnetic processes. Starting from the direction of the road, how far is the petrol pump, where is the road broken, where is the road closed, what will be the traffic signal next all type of information are easily available.
Cities have been illuminated with the help of smart lights in a scientific way at a low cost in different places based on the demand for light. These smart lights run on solar energy (solar panels) and thus collect energy during the day and illuminate the sun at night. Smart street lights are turned on whenever a vehicle or person passes through its vicinity. By understanding the different places, they increase and decrease the light and stop the propagation of light. Home School-College Courts Roads Government Offices Hospital Nursing Homes Solar-powered smart light system is used by these solar panels everywhere so that electricity money and the environment can be saved.
Smart Parking Management:
The smart parking management system is enabled by in-ground vehicle detection sensors. These systems allow drivers to park their cars immediately by locating an empty parking spot in the city. As a result, the management of car parking has become very easy. This system allows the driver of any vehicle to send and book an acknowledgement to park their car in the nearest location, where there is a parking spot, to see if there is any vacancy in that parking spot. GPS system location trackers need to be in the car and in the parking spot. This greatly reduces traffic jams. Maintains vehicle security. And time-to-time vehicle acknowledgement is available on mobile phones.
Smart Traffic Signals:
A part of the CV2X (Cellular Vehicle for All) network is the Smart Traffic Light Signals in IoT. Using this network a traffic light is always in contact with road vehicles. Vehicles send real-time information to traffic signals, which are based on the traffic conditions of the vehicles. This enables you to switch lights on traffic signals. This helps reduce traffic congestion at road crossings and enables the flow of traffic in a busy city.
Water Level Monitoring System:
It can using water level monitoring system, smart buildings maintain the required amount of water. This wireless tank level monitoring system will alert the building members whenever the water level falls below a certain level. Water quality can also be accurately estimated by the presence of TDS, pH, and other sensors attached here. Gives members of the building enough time to call the municipality or water tanker supplier before running out of water in a building.
Security and safety measures:
Devices such as IP surveillance cameras and wireless alarms are attached to this system. CC cameras prevent unknown people from entering the building and assist in remote observation of the building. This reduces the risk of theft and helps identify people in unauthorized areas of the building.
Smart Waste Management:
About 4.6 kg of solid waste is generated per capita in any city The Internet of Things has come up with groundbreaking smart waste management solutions for collecting and managing such a huge amount of waste. This will reduce the cost of municipal waste collection, reduce the overflow of waste in any dustbin, and be able to predict the amount of waste generated anywhere. Smart lightning management will be able to prevent the release of harmful diseases and gases.
IoT Smart Waste Management whenever a dustbin is full so that the dustbin is emptied as soon as possible. Dustbins are embedded with sensors that constantly alert the municipality about their level and location. This makes it easy to keep the environment beautiful and dust free. The right decision can be made for smart waste management systems to keep the environment clean at very low cost and in a short period of time. All of these measures are very helpful in making life more digital in smart cities.
- Fleet Management and Vehicle Tracking
Fleet management solutions help keeps track of vehicles. GPS Fleet Management Solutions can be used by a city’s emergency authority for public safety. This system can be used to track stolen vehicles, ambulances and fire trucks can use it to get to the fire truck as quickly as possible.
Fleet management solutions in smart cities increase the use of couriers and smart delivery A fleet manager can keep his trucks and ships ’trucks and make sure, that his ship’s products are safe and secure at every stage. A delivery person can easily know the delivery location and the shortest distance to get there by connecting to the smart city network.
IoT Security and Privacy:
There are risks with the unprecedented growth in the deployment of smart IoT technology. As the rate of data protection and privacy has increased rapidly. Security has deteriorated on IoT devices to exclude some limited resources and sophisticated cryptographic techniques. As a result, all of these places are at risk of various types of Internet attacks, such as privacy of service leaks, personal data attacks, and data theft, Virus attack. Recently, there have been numerous research proposals on IoT security and privacy. Nevertheless, there is still a security gap. For example, most of the proposed methods target one or two security requirements, such as privacy and authentication. An efficient and reliable IoT needs to share the necessary services for data sharing All organizations need to keep in mind that just as IoT devices are advancing people towards the well-being of society, they should not ignore its darker aspects.
The easiest and most natural way of communicating with human society is through the medium of sound. Research over the past few years has made it possible for humans to communicate with machines using natural language, thus giving birth to the AI conversational machine-human environment. It connects human conversations to machines using text-based or voice-based applications.
These conversational agents can be imagined as a natural interface for IoT devices. The integration of IoT and AI has successfully developed a conversational approach. Many applications are already being used in people’s daily lives, such as smart offices, smart homes and smart vehicles. Google Home is the first to transform our home into a smart IoT home. Which is very flexible to work Amazon’s Echo is another sophisticated device that offers more and more advanced features than Google Home. Listening to the surroundings of the house for Amazon echo sounds or alarms can guard the house in the absence of the owner. It only helps to make purchases from Amazon through voice instructions and informs the owner when the parcel arrives. Each user can know their account details using voice activation. Along with the advantages, this system is plagued with many limitations can be considered as research challenges Many times the user’s personal information is leaked Disclosure of this user’s confidential information may pose a risk to one’s privacy, For this reason, technology is needed where multiple users can provide their data with security and confidence IoT conversations such as “Turn on the TV” or “What is room temperature?” works on such simple instructions. In this way, a medium has been created between man and machine by easily accepting complex and simple conversations. This requires extensive research.
In many countries, most healthcare services are inefficient, slow and flawed. It can be easily changed and improved depending on the IoT smart device This technology can facilitate various activities in a very short time This IoT Smart Platform can further improve healthcare by keeping records of multiple people and providing medicines. The IoT smart application has many advantages over patient, staff and object tracking, identification and data processing. This makes it easier to maintain each patient’s record and research the next step with the help of sensor devices, it becomes very quick and easy to examine patients and reach health-conscious conclusions.
Smart Agriculture and Water Management:
IoT tests soil moisture and strengthens and improves the agricultural sector by monitoring stem diameter. This can control the number of vitamins found in agricultural products Microclimate conditions can be controlled to produce and preserve vegetables and fruits and to judge their quality. Weather studies, snow levels, drought measurements, wind changes, and rain or snow forecasts are possible. In addition to fungi, other bacterial contaminants can be prevented Temperature and humidity levels can be controlled In the case of cattle. IoT can detect animals in the open, detecting harmful gases from farm excrement. This can contribute to the health and survival and the growth of children. By implementing IoT in agriculture, a lot of waste and looting can be avoided through agricultural monitoring techniques and management. It can control the supply of electricity and water very well.
IoT plays an essential role in human life, from humans to animals, and plants, everyone is affected by an unhealthy environment in one way or another. Much effort has been and is being made to reduce pollution and waste of natural resources, as well as to create a healthier environment. Ways of a smart environment are needed to help monitor and manage environmental waste. It can provide the right amount of data As a result. The government takes the initiative to do proper monitoring and beneficial work. Such systems are being used to protect the environment. This leads to the dream of creating a beautiful life and a green world. IoT technology allows for monitoring and management of air quality by collecting data from remote sensors. Provides round-the-clock geographic coverage to handle traffic jams in major cities along the way. IoT technology can measure levels of water pollution. In weather forecasting, IoT can provide an accurate and high resolution through weather monitoring through data exchange and data planning. Through this technology, it can collect barometric pressure, humidity, temperature, light, speed and other information from moving vehicles and transmit the information to weather stations.
Advantage of IOT:
It provides various benefits in our daily life. Some of the benefits are:
- Minimize human performance: The use of IoT devices has greatly reduced human labour. As a result, people’s thinking has improved and their efficiency has changed.
It has been possible to save time: it saves us a lot of time. One of the primary benefits of using the IoT platform is.
- Data Collection: Even if we are far away from our actual location, we will continue to get the data we need from time to time. This is possible for real-time updates. This allows these devices to access data from anywhere at any time on any device.
- Improving security: If we have a mobile phone and an internet connection, it is possible to communicate with the rest of the world at home. As a result, these methods focus on greater security and privatization
- Reduce the use: With very few tools in this management, everything can be limited. Data can be exchanged with the rest of the world through a mobile phone and an internet system. That is why the use of additional electronic equipment is slowly declining As a result, waste of electricity is reduced
- Traffic Systems: Proper tracking systems are maintained using IoT technology.
- Useful in the healthcare industry: Patient care, doctor’s advice, and additional equipment meet the need for this IoT smart healthcare system.
The disadvantages of IoT are:
Just as the Internet of Things has its advantages, its disadvantages cannot be forgotten. Here are some of the disadvantages of IoT:
- Security issues: IoT systems communicate over a network. Thus, despite having a security system, they are not fully reliable and can result in a variety of network attacks.
- Loss Privacy: Our own personal data can be stolen by any type of network attack.
- Unemployment Causes: Unskilled workers or skilled people are also at high risk of losing their jobs as a result, resulting in high unemployment rates day by day. Today, people are getting intelligent surveillance cameras, robots, intelligent ironing systems, intelligent washing machines and other facilities at very low cost. As a result, people no longer need to do these tasks manually
- Increasing system complexity: The complexity of any system for designing, developing, and maintaining advanced technology in IoT systems is increasing day by day.
- Full System Crash: If for any reason the whole system is lost then all the data will be lost at once.
- Internet: Since IoT is an entire system online and dependent on the Internet, this system is completely reliant on the Internet to run all devices simultaneously around the world.
- Mental and physical effects: As the days go by, people are becoming increasingly dependent on the internet and smart devices, resulting in mental and physical disabilities. This is the way to do it today by clicking a button on a smart device instead of using physical force.
IoT sensors and advanced smart devices serve as the basis for building smart cities. This allows the public to experience living in a digital and smart environment. Cities are gaining the ability to improve their day-to-day operations, and city infrastructure is becoming more advanced and modern.
All of these IT centres and smart devices have made cities safer, faster, brighter and smarter. As the acceptance of IoT in various fields has increased, these smart cities are going to be the next big thing.
The Internet of Things (IoT) has been a very important place for research and development for more than two decades. However, there has been a lot of exciting activity in other areas, including the government sector, self-development and research, thanks to the contribution of this IoT device. In this research paper, we have identified the uses and disadvantages of IoT in various fields and hope to stimulate further research in this vibrant area.
- https://thesai.org/Downloads/Volume10No6/Paper_11 Internet_of_Things_IOT_Research_Challenges.pdf
- L. Militano, M. Nitti, L. Atzori, and A. Iera, “Enhancing the Navigability in A Social Network of Smart Objects: A Shapely-Value based
- Approach,” Computer Networks, vol. 103, pp. 1–14, 2016.
- M. Nitti, L. Atzori, and I. P. Cvijikj, “Network Navigability in the Social
- Internet of Things,” in Proc. of the IEEE world Forum on Internet of Things (WF-IoT 2014), Seoul, South Korea, 2014, pp. 405–410.
- M. Nitti, V. Pilloni, and D. D. Giusto, “Searching the Social Internet of Things by Exploiting Object Similarity,” in Proc. of the IEEE World Forum on Internet of Things (WF-IoT 2016), Reston, VA, USA, 2016, pp. 371–376.
- M. Nitti, R. Girau, L. Atzori, A. Iera, and G. Morabito, “A Subjective Model for Trustworthiness Evaluation in the Social Internet of Things,” in Proc. of the IEEE 23rd International Symposium on Personal, Indoor and Mobile Radio Communications (PIMRC 2012), Sydney Australia, 2012, pp. 18–23.
- M. Nitti, R. Girau, and L. Atzori, “Trustworthiness Management in the Social Internet of Things,” IEEE Transactions on Knowledge and Data Engineering, vol. 26, no. 5, pp. 1253–1266, 2013.
- N. B. Truong, H. Lee, B. Askwith, and G. M. Lee, “Toward a Trust Evaluation Mechanism in the Social Internet of Things,” Sensors, vol. 17, no. 6, p. 1346, 2017.


Anser EMT is an open-source electromagnetic navigation platform for research use. The system can be readily build from the design files provided in this project. This page provides a brief summary of the system design. Detailed implementation details can be found in the wiki.
The Anser system is comprised of eight systems.
- A signal generator
- An AC amplifier
- A field generator
- A tracking sensor coil
- A sensor amplifier
- A data acquisition unit
- A signal demodulator
- A position and orientation algorithm
This provides the source signal for the emitter coils of the field generator. Eight individual waveform generators ICs produce a set of sinusoidal signals in to 20kHz band for amplification.
AC current amplifier
A closed loop AC amplifier increases the power gain of the generated sinusoidal signals. This power gain allows the signal to drive the eight emitter coils to produce a time-varying magnetic field.
This coil produces a time-varying voltage signal when placed in the working volume of the field generator. The signal is a superposition of voltages induced by the time-varying magnetic field from each emitter coil.
The induced sensor voltage is very weak, on the order of microvolts, and requires filtering and amplification before being sampled. This instrumentation amplifier circuit conditions the signal in preparation for sampling.
Once conditioned, the tracking sensor is sampled by a data acquisition unit (DAQ). A current sense signal from the emitter coils is also sampled in order to determine the relative phase angle sensor voltage. Anser uses a National Instruments DAQ solution, but alternative/custom solutions may be used instead.
The tracked sensor signal and emitter current sense signals are both superpositions of eight frequency components, with each component due to a single emitter coil. Synchronous demodulation in software allows the magnitude and phase of each frequency component to be measured.
Position and orientation algorithm
The magnitude and phase information of each frequency components is fed into the position and orientation algorithm. The algorithm's minimisation process yields the position and orientation of the tracking sensor in space as a 5 degree of freedom vector:


A cable modem transmits digital data over existing cable television lines and it operates without a phone line, so you always stay connected at all times. The speed at which it sends and receives data varies from just a few Megabits per second (Mbps) to many Megabits. In larger towns and cities, cable continues to offer higher speeds at lower cost. We work with all major cable operators and you work with us.
Where available, Fiber Optic Service (FiOS) offers virtually unlimited data access speeds, unprecedented quality and high reliability. Unlike DSL which uses an existing business phone line, FiOS requires that a fiber optic cable be run to your business. DSL is fast, but FiOS is incredibly fast and can send data over much greater distances while maintaining speed.
Remarkable technological improvements in recent years have produced robust and reliable wireless services. As one of the leaders and early adopters of terrestrial wireless service more than a decade ago, we’ve been at the forefront of providing service to thousands of rural customers in the midwest.


Many people use wireless networks for convenience and flexibility. Wireless can be provided at hotels, coffee shops, or libraries. If not properly configured, wireless networks could provide a way to listen in on your computer's communications, risking your personal information.
Wireless networks should be configured for encryption, specifically a form called WPA or WPA2. This type of encryption should require a password that is complex and unguessable to access.
|Tip: For best security, use WPA2 – AES and a very long pass-phrase (20 or more complex characters). Don’t worry; you usually only have to use that pass-phrase once!|
If you have wireless at home, configure it for security, and customize important settings. Default passwords (those provided by hardware makers) should be changed, and wireless passwords should be something you choose.
If you are a business and provide customers with wireless Internet access, ensure these wireless systems are completely isolated from your internal computer systems.
Not all types of your personal information are at risk from unsecured wireless networks. Certain secure sites (like www.associatedbank.com) employ security that prevents eavesdropping, but you should still take extra precautions. If you have to use unsecured wireless networks, use them only for casual web browsing.
To learn more about wireless security, visit the Federal Trade Commission’s website Onguardonline.


Designing a social network system is not an easy task. As currently social networking systems are the most used internet services with huge, connected users and data generators. These services ingest and flow TBs of data daily. Due to this these systems poses many challenges which need to be addressed such as scalability, security, privacy, moderation, and user experience.
When designing such a system, some of the main challenges include Scalability, High Availability, Performance, and Security. I will not cover Compliances in this post.
In this post, I will try to come up with a system design for Social Networking services with the following basic functional and non-functional requirements.
In this post, I am going to touch following functional requirements.
- User management
- Users can follow each other.
- Make a friend.
- Users can post on their own and friends’ timelines and can post photos, Videos, and other media.
- Should be able to see posts with likes and comments.
- Followers/Friends can see others’ posts on their timelines.
- Users can like and comment.
- Users should get a notification for likes, comments, follow, and friends’ requests.
- Very Basic analytics for Post encasements, User activity, Hash Tag Trends, etc.
Social networking services are platforms that allow users to interact with each other through various types of media. Users can post text, photos, videos, and other content, as well as like, comment, and share them with their connections. These activities generate terabytes of data every day, which need to be stored and processed efficiently. Social network systems are designed to handle more read operations than write operations, so they must be optimized for performance and scalability.
- High Availability
Storage Size Estimation
A simple storage estimation will help in understanding scalability and performance requirements. For this check table below.
Imagine a system with 5 million active users who each do 5 activities per day and generate 1 MB of data per activity. That means the system needs 25 TB of storage every day and 9 PB every year. That’s a lot of data to handle, process, and store. It makes the system’s scalability, availability, and performance more challenging, but also more exciting.
Basic Data Modeling for Social Graph
Let’s define basic entities for our social network requirements and establish relationships among them to create a basic graph for our system. Using these related entities our system would be able to create a social graph of our connected users. For more details read this
- user: User table to store user information, id is the primary key, email, and mobile number are unique fields.
- user_follower: This table records the user followers and their types. The types can be Like, Dislike, or Follow, indicating how the followers interact with the user
- user_friend: The User Friend Table keeps track of the user’s friends. The friend status column indicates the current state of the friendship and the type column specifies the kind of friendship.
- user_post: The User Post Table stores the posts made by the users. The sender can choose to let other users with the right permissions post on their wall.
- user_comment: The post comment table stores comments by users on posts. The ParentCommentId column would be used to store nested comments.
- user_notification: The user notification table stores notification generated for different events for users with a status column which would be used to track notification status like generated, delivered, and viewed.
- user_media: The metadata and object URI of the media files uploaded by users and included in their posts will be stored in this table.
- user_post_media: This table will store information for the media files used in a post.
High-Level View of the System
We are going to design a Social Networking Service where users can register themselves using a client app, then can make friends and follow others. Users can post status text, photos, videos, etc. on their timelines and others as well. Users can view others’ statuses like a comment which is naturally going to make this service high-read and highly eventful (Comments, like, etc.).
First, we are going to describe very high-level components going to be used in this system. Later in this post, we are going to detail these components.
- Client: A social network client application is a software program that allows users to access and interact with a social network service. It may provide features such as browsing, posting, messaging, commenting, liking, sharing, and following other users. A social network client application can be web-based, desktop-based, or mobile-based, depending on the platform it runs on.
- API Backend: The API backend consists of a set of backend API services that handle various operations. These services interact with OLTP Datastore, Object Store, Message broker, and OLAP to store and retrieve information efficiently.
- Data API: This system will offer a layer of abstraction for the underlying database and enable very high-performance read-write APIs for the datastore, allowing the API backend to operate independently.
- OLTP Datastore: To store our data, we need a database system that can handle high volumes of transactions and ensure data availability. This is why we will use an OLTP data store for our OLTP needs. We will use a shared database with global replication to support the Peta Byte scale.
- Object Store: This is a storage system that can handle and deliver any media file. It has high availability and scalability features.
- Message Broker: A message broker is a software component that enables asynchronous communication between different systems or applications by handling events and data with high performance.
- Processes: This component consists of multiple processes that run in the background and handle asynchronous and batch operations. This will communicate with the message broker, OLAP, OLTP, and cache to read input and update results.
- OLAP: These systems are software tools that enable users to analyze data from multiple perspectives and dimensions. We will use this to generate different insights for users.
- Cache: To improve performance and reduce latency, any scalable system needs a cache. Our system will use a cache (both distributed and in-memory) with most of its components.
- CDN: To speed up the delivery of media files, static resources, and post content, we would use CDN. CDN is a network of servers that caches and distributes these assets to the users. This way, we can enhance performance, reduce latency and increase scalability.
All the above components should be designed and used to achieve our functional and non-functional requirements. Let’s keep the client for later or we can keep out of this design scope.
API Backend Design
An API backend is a service that runs behind a load balancer and offers an HTTP-based API for communication with other services or databases. It provides the data, computation, actions, activities, and events that the front-end interface needs to interact with the user.
In the case of our Social Networking Service API backend will look like this.
We can use Microservices style architecture for API backends. Frontend and client requests will come through one Application load balancer which will be further routed to API gateways.
API gateways will do some basic checks on request the route request to the respective service. Services will communicate with backing services like database, object store, message queues, and cache and perform operations.
Each service is scalable, highly available, resilient, secure, and concurrent.
- Load Balancer: A load balancer is a device or software that distributes network traffic across multiple servers. It improves the performance, reliability, and scalability of web applications. In our case, this load balance will be Infront of the API gateway service to distribute loads across multiple API gateway servers.
- API Gateway: An API gateway server is a software component that acts as an intermediary between clients and backend services. It provides a single-entry point for all requests and can perform tasks such as authentication, routing, load balancing, caching, and monitoring. An API gateway server can improve the performance, security, and scalability of an application.
- Authentication Service: This service will verify the identity of users and API requests. It will also check the permissions and roles of the users and requests. API Gateway will rely on this service for authentication and authorization.
- User Service: This service allows users to sign up, manage their profiles, and connect with other users.
- User Read-Only Service: This service provides read-only access to user data, such as profile details, friend lists, and follower connections.
- Post Comment Like Service: This service provides API to create and manage posts, comment and liken on posts, etc.
- Media Service: This service will provide functions to upload and manage users’ media used in posts.
- Timeline Service: The timeline service is responsible for creating the timeline data for each user, which shows their activities and updates. The service relies on cached data and other OLAP processes that run in the background to generate the timeline for each user.
- Notification Service: This service is responsible for providing and managing notifications to users of different activities and recommendations. The service relies on other service data, cached data, and other OLAP processes that run in the background to generate the notification for each user.
- Post Rendering Service: This service is responsible for displaying posts. It will access the post content, media information, comments, and likes, and send them to the user application for rendering. This service can also use CDN to reduce latency and enhance performance.
- Cache: To reduce the delay and enhance the efficiency of any social media platform that handles a lot of read requests, we will employ a distributed cache system along with all services.
- Search Service: This service will act as a proxy to the OLAP database, free text search, analytics results, etc.
Data API Design
Data API is an abstraction over the OLTP database to Backend API services. It will provide API to perform the read and write of data. All underlying operations like Shard Identification, database connection, and unique id generation for each record will be done by this component.
- Load Balancer: This Load balancer will distribute read/write data requests based on the shard key. Underlying services would be connecting to assigned shard db to perform database operations via Shard Proxy.
- Unique ID Generator: This service will be used to generate global unique database id keys only. This service will have n nodes across the data center connected via a gatekeep to generate a unique id for database table keys. This service can be discussed in a separate post. System design : Distributed global unique ID generation | by Sandeep Verma | Medium
- Data API Nodes: For read operations only a read replica of a shard will be used and for write operation master node of the shard will be used. Each node has a connection pool of assigned shards. We can use a gatekeeper to shard assignments and rebalance dynamically.
- Shard Proxy: This component routes requests based on sharding keys. It is essential for the whole system and may need a third-party or open-source solution. Alternatively, one can create it using custom techniques. This component deserves a separate topic for discussion.
OLTP Datastore Topology
Online transaction processing (OLTP) is the term for using computer systems to manage transactional data. OLTP systems capture and store the data from business interactions that happen in the daily operations of the organization and allow querying of this data to draw conclusions.
For this service, we will use RDBMS as this is best suitable for structured and transactional databases with strong consistency.
But all transactional features of RDBM create challenges in achieving scalability, availability, and performance for the Peta Byte scale. This scale cannot be achieved out of the box from RDBMS systems. We need to go for some Enterprise grade licensed database systems like Oracle, Google Cloud Spanner, or some third-party managed Open-source databases.
To handle massive amounts of data with open-source RDBMS, we need to design systems that can manage shards, connections, and some aspects of replication. This is the approach that Facebook, Twitter, and other companies use.
We can think of the following sharded RDBMS topology with across-data center replication for our service.
- Shard Manager: The Shard Manager is in charge of handling the distribution and coordination of shards among different data centers. It can also create new shards or delete existing ones, and adjust the shard allocation as needed.
- DB Instance: This is the master node of a shard. This topology will support multi-master replication across data centers.
- Read-only Replica: Read-only replica is replicated data node of a shard this can be used for reading and standby nodes and also for any failover. For each shard replication will be across data centers for high availability.
- Replication: This component will be used to manage the replication of the shard.
Events and OLAP
For social network event real-time and analytics processing, we need one highly scalable Message Broker to ingest millions of messages per minute and one highly scalable OLAP database (No SQL) with text-based search and analytics capabilities. To handle a burst of query requests to OLAP we will use one proxy in API Backend.
- Message Broker: All events will be pushed to message broker topics for asynchronous processing. The broker processor process will process messages and store them in the NoSQL database.
- API Backend will also update some data like text posts and comments to NoSQL for search and analytics.
- Process: These are message and batch processes and those will also update the cache, OLTP, and OLAP database with analytics and aggregation results.
Database Table Partitioning & Duplication
In Database partitioning, You can split tables, indexes, and index-organized tables into smaller parts, which makes it easier to manage and access these database objects. Most of the Database engines including open-source community editions support different types of table partitioning which is transparent in SQL and can be used with any application. Read more here
- MySQL :: MySQL 8.0 Reference Manual :: 24 Partitioning
- Partitioning Overview (oracle.com)
- PostgreSQL: Documentation: 15: 5.11. Table Partitioning
Table partitioning in a single node is basically of two types ie. horizontal and vertical. Since by doing sharding, we are already horizontally partitioning tables across the shard nodes but we can still partition tables in one shard for better performance. For example, take below 2 cases:
- In the post table, we can partition the post table vertically. As post content is text type can be long size text, which can increase table size very rapidly, we can store post content in another table or in some key-value store system(NoSQL). This will help in performance improvement.
- As there can be thousands of comments and likes for a post, we can partition the comments and likes table horizontally in the same shard using the post id hash or putting some virtual column(expression-based horizontal partition or interval partition post created month).
Apart from Partioning, we can replicate both the lookup table and the user table across all shards. This will help in executing queries by using joins.
The flow of Some Functional Requirements
For all use activities, the client will send requests to Backend API services via API Gateway. API Backend will call Data API to perform data read-write into OLTP.
For write requests, API backends will update the cache, and for read first API backend will try to get data from the cache. We can also leverage caching in Data API services to improve performance.
For each user activity API backend services will publish the activity message to the message broker to do OLAP processing. OLAP will also update data in the cache and OLTP.
When any user opens the client app, the first thing he sees is his timeline. So rending a user’s timeline in milli seconds latency is very critical for a great user experience.
To Build a timeline we can think to show his friends and followers post updates, notification counts, and a list of notifications and other updates. To build a timeline we can use a ranking system with parameters like date create, no of like, no of comments, no of views, etc.
To provide a great user experience we need to show a timeline in very less time for this we can use background processing to keep updating the user’s timeline in a scheduled interval in the cache. Here we can also filter users by their activity frequency means we will keep updating the user’s timeline according to his/her activeness in the service.
After showing the user’s timeline from the cache, we can send another request to update the user’s timeline immediately with the latest updates.
As in design, we are using CDN for the delivery of media files, we can also leverage CDN to search post-rending. We just need to configure the post rending service as a source for CDN and send CDN URL as a post URL. In case of post edit, we can make the post URL with a different version
Handling of Like, Comments, and Views
Post likes, comments, and views are asynchronously written to the database because in many cases there will be thousands of events per second and synchronous write will cause problems. All these events are sent into a very scalable messaging system where they are processed in batches to OLAP and OLTP systems to handle bursts.
This message broker’s ques can also be used to update posts and users ‘KPIs and send real times notifications.
Analytics for real-time trends and #tags
In the OLAP system, we can use ElasticSearch for a period to compute trending topics and #tags. A background process will do the processing of post text to count topics, #tags, view, and other KPIs to rank topics and #tags.
Challenges Involved In the Development of Social Networking System
Social networking systems are platforms that allow users to interact with each other online. Developing such systems involves many challenges, a few are given below.
- Maintaining the performance and scalability of the system, especially when dealing with large volumes of data and traffic.
- Ensuring the security and privacy of user data, especially in the face of cyberattacks and malicious actors.
- Providing features and functionalities that meet the diverse needs and preferences of users, such as personalization, customization, and accessibility.
- Balancing the trade-offs between innovation and regulation, such as complying with ethical and legal standards while offering novel and creative services.
Basically, all non-functional requirements are challenges in developing such systems. But according to me scalability, performance, and legal compliance are some of the most challenging tasks.
A good architecture and system design can solve all these problems so one can say good system Architecture and design is the most challenging task.
If you go by all the items discussed in this post then we can say the design of the OLTP part is the most challenging, Data API, Database sharding, and Replication is the most challenging part.
Sample Tech Stack over public cloud
Now we can explore what tech stacks we can use to develop this service.
- K8S: For Microservices
- Redis culture for cache
- For OLTP, MYSQL sharded database with the regional replication or we can use both the Graph Database and RDBMS of our choice. Google cloud spanner is also a good choice for Managed Database which provides scaling, and replication across regions.
- For OLAP, Elastic Search with regional replication or Elastic Search with global Cassandra.
- Cloud object storage like S3
- Managed cloud CDN service
- Managed Cloud API gateway.
- Managed Kafa clustered with regional replication.
- Cloud-managed DNS service for regional request routing.


What is it: The Afterglow Karga headset is an exclusive Xbox One headset wireless to the console. The headset sports a hybrid of the newest Afterglow headset design with a split cushion headband to relieve tension from the apex of your head, but also blends traditionally favored assets such as the 50mm driver speakers, rounded ear cushions with extra back padding, and the retractable noise canceling microphone boom. This headset is compatible with the Xbox One, but also includes an auxiliary cable for mobile device compatibility.
- The comfortable ear cushion material and design are engineered for long lasting gaming periods.
- Over the ear cups bring users into an immersed experience with amazing sound quality that their games deserve.
- The noise cancelling microphone is flexible and allows users to communicate clear and effectively with fellow gamers.
- The Karga is compatible with the Xbox One and other mobile devices (using the grey auxiliary cable included).
- The split headband cushion design prevents pressure build up on the apex of the user’s head, allowing a comfortable, long lasting gaming experience.
Did I Like It? In a nutshell yes! The headphones synched effortlessly to the console and the cans and strap fit perfectly over my head without digging in and becoming a hindrance.
The battery life surprised me and the ability to use the AUX cable, meant I could use it on my PS Vita (blasphemy!) and phone for music as well. The chord was a small annoyance but only because I was used to using these wirelessly with the console.
Chat wise the quality was crisp and clear, a lot of this does come down to internet speed, but I found it be to perfectly suited to frustratingly annoying wait times in Halo matchmaking.
Overall these headphones are the real deal, they look beautiful with their green glow, and the functionality delivers high audio quality for in and out of the gaming environment.
Afterglow Karga Headphones can be picked up at EB Games
Be the first to leave a review.


A tire pressure sensor programmer is a device that is used to program or reprogram the sensors in a vehicle’s tire pressure monitoring system (TPMS).
TPMS is a safety system that monitors the air pressure in the tires of a vehicle. The sensors are mounted inside each tire and send data to the vehicle’s computer, which will alert the driver if the tire pressure falls below the recommended level or if there is an issue with the system.
The tire pressure sensor programmer is a common automotive electronic device, which is mainly used to detect and adjust the pressure of the vehicle tires. Its working principle is to transmit the real-time pressure data to the programmer for analysis and processing by detecting the pressure sensor inside the tire and calculating the accurate tire pressure value according to a specific algorithm.
1. Working principle of tire pressure sensor programmer
The tire pressure sensor programmer is a tool for the tire pressure monitoring system of the vehicle, which can program and calibrate the tire pressure sensor of the vehicle. The operation of this device is very simple, just insert the programmer into the OBD port of the vehicle, and then operate according to the prompts of the programmer to program and calibrate the tire pressure sensor. The vehicle’s tire pressure monitoring system is a very important safety device. It can monitor the tire pressure of the tire. Once the tire is abnormal, such as the tire pressure is too low or the tire pressure is too high, the system will immediately send out an alarm to remind the driver Handle it in time to avoid traffic accidents. Therefore, it is very necessary to program and calibrate the tire pressure sensor of the vehicle, which can not only ensure driving safety but also prolong tire life, improve fuel efficiency, protect the environment, and save money. The tire pressure sensor programmer is widely used in the vehicle maintenance industry and tire pressure monitoring system manufacturers, which greatly facilitates vehicle maintenance and management, and also improves the operating efficiency and safety of the vehicle tire pressure monitoring system.
2. Introduction of tire pressure sensor programmer
In some cases, such as when new tires are installed or when the system is repaired, the sensors may need to be programmed or reprogrammed to ensure that they are working properly. This is where a tire pressure sensor programmer comes in, allowing the user to communicate with the sensors and adjust them as needed.
The tire pressure sensor programmer can receive information from the vehicle’s computer about the number and location of the sensors and can then program them to operate at the correct frequency and pressure levels. Some programmable sensors can also be configured wirelessly, using devices like smartphones or tablets, or they can be programmed manually through a dashboard display.
The tire pressure sensor programmer is a very practical automotive electronic device, which can effectively ensure the driving safety and comfort of the vehicle, and also prolong the service life of the tire. With the continuous development of intelligence and automation technology, the application prospect of the tire pressure sensor programmer is also expanding, and it will become one of the important research directions in the field of automotive electronic equipment in the future.


- Google Wifi is a new kind of Wi-Fi solution that replaces your router (and works with your modem and ISP) to give you seamless coverage throughout your home.
- Say goodbye to dead zones with Wi-Fi that's made to fit your whole home.
- Family-friendly tools, Google Wifi allows you to pause the Wi-Fi on kids? devices, like during bedtime or dinnertime.
- A single Wi-Fi point covers up to 1,500 sq. ft., and a set of three covers homes up to 4,500 sq. ft. Wi-Fi points work together so you can add more if you need additional coverage.
- Requirements: Google account, Android device (Android 4.0.3 or higher) or iOS device (iOS 8.0 or higher), Google Wifi app, Broadband Internet connection, Each Wifi point requires a nearby electrical socket
|Compatible devices||Smart Television, Smartphone|
|Item weight||703 Grams|
|Number of ports||3|
|Item dimensions L x W x H||14 x 10.2 x 14 Centimetres|
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[winswitch] Xpra for linux, windows, osx,
lonnie at outstep.com
Tue Apr 2 00:39:44 BST 2019
I have recently been looking at Winswitch but think that now maybe Xpra is
more of what I need for my project in that I need to be able to use
seamless mode to be able to connect windows and linux applications to
display seamless on a desktop.
I know that Xpra can handle Linux seamless windows but can it handle
windows applications in seamless mode as well?
Also, I am interested in being able to pass audio and video streaming, too
Lonnie T. Cumberland, PhD.
Email: Lonnie.Cumberland at Outstep.com
More information about the shifter-users


Wi-Fi has become an essential part of daily life, seamlessly connecting you to the internet without the clutter of cables. It’s a technology that uses radio waves to enable wireless networking among devices.
When you use Wi-Fi, your device communicates with a wireless router that’s connected to the internet. This allows you to browse the web, stream videos, and check emails without a physical connection.
There are various types of Wi-Fi networks to consider, each with its own features and specifications. You might have come across terms like 802.11ac, 802.11b/g/n, and more recently, Wi-Fi 6.
These names refer to different Wi-Fi standards that dictate the speed, range, and capacity of wireless networks. Upgrading to a newer standard usually means better performance, but compatibility with your devices is key.
Securing your wireless network is vital to protect your personal information from unauthorized access.
Simple steps like setting a strong password, enabling network encryption, and keeping your router’s firmware up to date can make a significant difference.
Also, be aware of where you’re accessing Wi-Fi; public networks can be convenient, but they’re also more vulnerable to security risks.
Fundamentals of Wi-Fi
Before diving into the nitty-gritty, you should know that Wi-Fi lets you access the internet wirelessly through radio waves, enabling connections without physical cables.
Wi-Fi Technology Explained
Wi-Fi is essentially a wireless technology that allows your devices—like smartphones, laptops, and smart TVs—to connect to the internet or communicate with one another without being tethered by wires.
At its core, Wi-Fi converts data from your device into a radio signal, which is transmitted by a wireless adapter and received by a Wi-Fi router. That router then decodes the signal and sends the information to the internet through a wired connection.
Standards and Protocols
Your Wi-Fi isn’t a one-size-fits-all technology; it operates based on specific protocols known as IEEE 802.11 standards. These standards define how Wi-Fi networks communicate and vary in speed, range, and frequency.
Important Wi-Fi standards include:
- 802.11a/b/g/n/ac/ax: Each represents an evolution in speed and efficiency. The latest, 802.11ax (also known as Wi-Fi 6), is all about higher data rates and tackling congestion when multiple devices are connected.
|Max Speed (approx.)
|802.11n (Wi-Fi 4)
|802.11ac (Wi-Fi 5)
|802.11ax (Wi-Fi 6)
Wi-Fi operates mainly on two frequency bands:
- Better at penetrating obstacles, hence, wider range.
- More susceptible to interference because many devices use it (microwaves, Bluetooth, etc.).
- Offers higher data rates and less interference.
- Has a shorter range due to higher frequency, which doesn’t penetrate solids as well.
Understanding these bands is key to optimizing your Wi-Fi network’s performance.
Types of Wi-Fi Networks
Wi-Fi networks vary based on their intended use, coverage area, and security protocols. Here’s what you need to know about the different setups.
Your home network is typically set up with a single Wi-Fi router that provides internet access to your devices.
This router connects to your internet service provider (ISP) and broadcasts a wireless signal throughout your home. Home networks usually support a protocol called WPA2 for security.
Public Wi-Fi networks are available in places like coffee shops, airports, and libraries. These networks are convenient, but they’re not always secure since they’re open to everyone.
They often have no password, or a shared password displayed in the area, which makes them more vulnerable to security threats.
For businesses or large organizations, enterprise solutions are more robust. These networks use advanced security protocols like WPA2-Enterprise or WPA3 which incorporate individual user credentials for access.
They also typically involve more sophisticated network hardware to accommodate a larger number of devices and to provide coverage over greater areas.
Setting Up a Wireless Network
When setting up your wireless network, the right equipment and proper configuration are crucial for a seamless online experience.
Begin by choosing a Wi-Fi router suitable for your space and usage needs. This is your network’s backbone, determining coverage and speed. Consider routers with dual-band capability, which support both 2.4 GHz and 5 GHz frequencies, for better performance.
Next, ensure your devices are equipped with Wi-Fi adapters. If they aren’t built-in, USB or PCIe adapters are available.
For larger homes, consider mesh network systems or Wi-Fi extenders to eliminate dead spots.
|Broadcasts Wi-Fi signal, connects to modem
|Speed, frequency, range, brand reliability
|Enables devices to connect to Wi-Fi
|Compatibility with router’s Wi-Fi standards
|Mesh Network Systems
|Provides extensive coverage without signal loss
|Number of units needed, compatibility with router
|Increases range of existing Wi-Fi signal
|Compatibility with existing network, placement
Installation and Configuration
Once you have your equipment, follow these steps:
- Position your router centrally and raised to maximize signal distribution.
- Connect the router to your modem using an Ethernet cable, then power it on.
- Configure your network through the router’s web interface or app. This will typically involve setting a network name (SSID) and a secure password.
- Enable security features such as WPA3 encryption to protect your network.
- For better control, consider creating a guest network and setting parental controls if needed.
Remember to regularly update firmware to maintain security and performance. Keep a note of your settings and passwords for future troubleshooting.
Enhancing Wi-Fi Performance
In your quest for a seamless online experience, fine-tuning your Wi-Fi performance is crucial. Small changes can yield significant improvements.
Your Wi-Fi router is the heart of your wireless network. Place it centrally in your home, elevated, and in the open—these tweaks let the signal spread evenly. Avoid closets and cabinets; they throttle your Wi-Fi’s potential.
Wi-Fi dislikes competition. Household electronics and neighboring Wi-Fi networks can cause interference. To dodge this:
- Switch channels: Your router can broadcast on several channels. Use tools to find the least crowded one.
- Update firmware: Keep your router’s software up-to-date for optimal operation and security enhancements.
If your router’s reach isn’t sufficient, consider these remedies:
- Mesh Network: An interconnected system of nodes that spread Wi-Fi throughout your space.
- Wi-Fi Extenders: Devices that boost your Wi-Fi signal range—place them at the edge of your current signal’s reach.
Securing Your Wireless Network
Keeping your wireless network secure is critical to protect your personal information and prevent unauthorized access. By using strong encryption, effective authentication measures, and keeping an eye on network activity, you can greatly enhance your Wi-Fi security.
To shield your data, it’s important to know that Wi-Fi Protected Access 3 (WPA3) is currently the most secure encryption standard you can use.
However, if your devices are older, they may only support WPA2, which is still reasonably secure. Always avoid using Wired Equivalent Privacy (WEP) because it’s outdated and vulnerable.
- Standard: Most advanced, secure
- Availability: Found on newer devices
- Standard: Secure, widely adopted
- Compatibility: Good for older devices
- Standard: Outdated, not recommended
Authentication and Access Control
Ensuring that only authorized users have access to your network is another key step in security.
- Unique and Strong Passwords: Create a password that’s a mix of numbers, symbols, and both upper and lower case letters.
- Network Name (SSID): Modify your Service Set Identifier (SSID) to something unique but not personally identifiable.
- MAC Address Filtering: This allows you to specify which devices can connect to your network. However, be aware it offers limited security as MAC addresses can be spoofed.
- Separate Guest Network: Enable a guest network to keep your main network more secure.
Stay vigilant by monitoring your network for any unusual activity.
- Regularly check the list of devices connected to your network.
- Use network monitoring tools designed for home use to keep an eye on incoming and outgoing traffic.
- Install firmware updates for your router. These updates often contain security improvements.


In an era of wireless and broadband communication, there are a plethora of companies offering competent services. The best among the best is, however, the ones that consider providing customer-centric services. Verizon Wireless is one such company based in New Jersey providing wireless services to most of the population in the U.S.
It is the biggest telecommunication company with over 159 million subscribers and providing 4G LTE services to 98 percent of Americans. What has been its success story? Who founded it? Through this article, we are going to reveal all this information & the current market value of the company. So read on!
The foundation stone of Verizon wireless was laid back in September 1999 when two established phone companies i.e., American Bell Atlantic and Vodafone AirTouch PLC of U.K. joined hands. This mutual venture of wireless phone service was of worth $700 billion. In 2000, the name Bell Atlantic was changed to Verizon wireless. Verizon then became the largest wireless company in U.S.A as approved by Federal Communications Commission in 2000.
Growth & Operations:
The company stood firm at its position until 2014. Verizon expanded it’s worth by acquiring more phone companies all through the 2000s. Companies acquired by it include SureWest Communications, West Virginia wireless and Ramcell among others.
The company did other big deals too such as buying Alltel which made Verizon wireless again the largest cellphone network of U.S. Verizon communication has acquired 45 percent shares of Vodafone becoming the sole owner of itself in 2014. New York Times has estimated the worth of the company at $290 billion.
Verizon wireless utilizes the “supercookie” mechanism a deep packet inspection tool which though is transparent to customers, was frowned upon by Electronic Frontier Foundation for possible violations. The company then established a system where the customers can choose to opt-out. Ronan Dunne was the company’s new president as of August 2016.
Verizon announced the unlimited data plan in 2017 to improve its quality and to win the race amongst other companies. It resulted in customer-oriented alterations in other company’s services too.
Continuing with the journey, Hans Vestberg is the new CEO from August 1,2018 as announced by Verizon.
Market Value & Large Acquisitions:
As you must have already adjusted yourself to the fact of Verizon being a large company both in worth & name, you might not know that the company has acquired lesser worth companies like AOL and Yahoo for combined $9.23 billion. If it was back in 2000, it must have cost Verizon no less than $364 billion, but as of today Yahoo and AOL might restore their lost value with the most prominent mobile company at their back.
The three most significant acquisitions done by Verizon include buying Alltel in 2008 for $28.1 billion, GTE in 2000 for $64.7 billion and 45 percent of Vodafone stakes in Verizon Wireless for $130 billion.
They have spent a lot and have accumulated enormous riches too. Being the highest ranking company as per annual revenue, Verizon stands at the market value of $188.7 billion with a grand turnover of $100 billion annually.


Greensboro, NC -- This week, March 3-9, has been declared North Carolina's Severe Weather
Awareness week for 2013. So far this week topics have included knowing
your risk, developing a severe weather action plan and building a severe weather preparedness kit.
Today's focus is on ensuring that you get the alert when severe weather threatens your area.
A quick and easy way to get severe weather alerts is to sign up for free severe weather text alerts from WFMY News 2. From tornadoes to winter storms WFMY will send you a free text message anytime a watch or warnings gets issued for your area. Sign up for these free text alerts by clicking HERE.
A NOAA weather radio remains one of the best ways to receive weather warnings, especially at night. NOAA Weather Radio is a nationwide network of radio stations broadcasting continuous weather information directly from the nearest National Weather Service office. NOAA weather radio broadcasts official weather service warnings, watched, forecasts and other hazard information 24 hours a day, 7 days a week.
In North Carolina nearly 30 NOAA weather radio broadcast stations provide weather forecast and warning information for all 100 counties. No matter where you live there is a NOAA weather radio station nearby.
NOAA weather radio will alert you 24 hours a day to the follwing weather hazards in your county: tornadoes, severe thunderstorms, flash floods, river floods and winter storms. Broadcasts are found in VHF public service band on seven frequencies ranging from 162.400 MHz to 162.550 MHz. These special receivers range in price from $20 to $65, though most cost less than $40.
The weather radios round-the-clock protection can be a life-saving investment and they can be found in most electronic stores and on many popular websites. When purchasing a NOAA weather radio, consumers are recommended to buy a radio with Specific Area Message Encoded technology, otherwise know as S.A.M.E. This technology allows the user to program specific counties into the radio so that it only receives alert for the desired county or counties.
More information about NOAA weather radios can be found here: http://weather.gov/nwr
To enhance public safety, a free Wireless Emergency Alert (WEA) service was introduced nationwide late in June 2012. WEA messages are text-like alert messages received by your mobile device during an emergency in your area. The purpose of WEA is to provide an increasingly mobile American public with a free and fast way to receive critically important information, including extreme weather alerts and other threatening emergencies in your area such as AMBER Alerts and Presidential Alerts during a national emergency.
For more information about WEA and other alerting methods visit www.ready.gov/warning-systems-signals.
Continue to check in on digtriad.com and watch WFMY News 2 for more valuable severe weather information. Severe weather season in
the Triad is from March-May, but severe weather can occur at any point
throughout the entire year.
WFMY News 2


Broadband Access For All U.S. Citizens by 2020
Matt | On 16, Mar 2010
I thought this was an interesting piece of info when I came across it on the BBC. The Federal Communications Commission (FCC) recently unveiled it’s “broadband plan” to give all U.S. residents high-speed Internet by 2020. This plan has had the strong backing of the tech industry for years.
My first thought was, “Well, I thought everyone had high-speed access?” Of course not! In 2010, nearly one-third of Americans (100 million) are without access to high-speed Internet. I live in a major city where I can call a cable provider or the phone company and get access. But, there are people that live in rural or under-served areas that have no access to high-speed Internet. Many have to use dial-up services, if they are even available. And let’s not bring wireless into the picture. You can almost forget it in certain places – especially since you need high-speed access to make wireless happen.
So, why do we need this? It’s very simple. In the 21st century, our citizens cannot be competitive in the global market without Internet access. The FCC, rightfully so, says that the Internet is changing education, healthcare, job creation, and quality of life. Very true. How else are we going to get those 100 million people reading Prune Juice Media?!?!
This plan does NOT give away free Internet access. It simply makes the option available, much like electricity, water, or gas. You have the OPTION of buying the service because it’s available in your area. The FCC is trying to step up the game the same way for the Internet too.


The Rugged Panel PC with an integrated “Rugged Display and Computing Unit” combines the durability and reliability needed for harsh environments with powerful processing capabilities, making it ideal for a wide range of applications in military, maritime, industrial, and other challenging environments.
Mentioned below are some of its key features:
- Integrated 15.1" LCD and Intel Core i7 or Xeon E3 or latest Processor: The rugged panel PC can include a 15.1" LCD display with a high resolution and brightness suitable for outdoor and challenging environments. is powered by an Intel Core i7 or Intel Xeon-E3 or the latest processor to ensure sufficient computing power for demanding applications.
- Custom Specific Function Keys, Storage Capacity, IO Ports, Input Power, and Mounting: The rugged panel PC can be tailored to include custom function keys, allowing quick access to specific functions or applications. It can also offer customizable storage capacity, providing ample space for data storage. Furthermore, the panel PC can be equipped with a range of IO ports to facilitate connectivity with various devices. The input power options can be designed to accommodate specific voltage requirements, and the mounting options can be flexible to support shipborne and ground deployment.
- Environmental Compliance as per MIL-STD-810F: The rugged panel PC is designed to meet the environmental standards outlined in MIL-STD-810F. This means it can withstand extreme temperatures, humidity, vibration, and shock, making it suitable for deployment in challenging environments.
- EMI/EMC Compliance as per MIL-STD-461E: To ensure electromagnetic compatibility, the rugged panel PC complies with MIL-STD-461E standards. This ensures that the system can operate without interference from electromagnetic fields and provides protection against electromagnetic emissions.
- Custom Designs: It can be customized to match specific requirements and designs. This includes considerations for the form factor, enclosure materials, sealing, and additional features needed for the intended application.


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Cisco TMS is unable to manage endpoints and an engineer is required to capture logs to determine the cause. What is the menu path that the engineer should follow to capture and download logs from Cisco TMS?
A. Administrative Tools > Diagnostics > TMS Tickets
B. Administrative Tools > TMS Server Maintenance > Download Diagnostic Files
C. Systems > Navigator > Diagnostics > Download Diagnostic Files
D. Systems > Navigator > TMS Logs
Correct Answer: B
A technician is trying to pair a Touch 8 with a Cisco TelePresence SX20 endpoint, but the codec is not automatically listed in the touch panel. What are two possible reasons for this behavior? (Choose two.)
A. The codec firmware version is below version TC 6.1.
B. The codec and the Touch 8 are on separate subnets.
C. Pairing visibility mode is not active on the codec.
D. The codec is not compatible with a Touch 8 device.
E. The Touch 8 is connected via the second Ethernet port on the codec.
Correct Answer: B,C
Which bridge solution requires Cisco TelePresence Conductor? 210-065 dumps
A. Cisco TelePresence Server operating in remotely managed mode
B. Cisco TelePresence Server operating in locally managed mode
C. Cisco TelePresence MCU operating in remotely managed mode
D. Cisco TelePresence MCU operating in locally managed mode
Correct Answer: A
Which two additional items can be configured for an endpoint to register with the Cisco TelePresence Video Communication Server for H.323 to function correctly? 210-065 pdf (Choose two.)
A. unique system ID
B. unique H.323 ID
C. unique DNS entry ID
D. unique E.164 alias
E. unique real-time transport protocol port numbers
F. unique NTP server IPv4 address
Correct Answer: B,D
Which Cisco TelePresence Multipoint Control Unit Layout view mode gives prominence to one conference participant over the other conference participants while still allowing conference participants to view multiple participants at the same time?
A. enhanced continuous presence
B. active speaker
C. continuous presence
D. room switching
E. speaker switching
Correct Answer: A
A video conference user that is connected via a Cisco TelePresence Codec C40 to a conference that is hosted on a Cisco TelePresence MCU 5300 would like to switch the local layout view. Which two options describe how to switch the local layout view without affecting the view of remote users? (Choose two.)
A. Use the Administrator settings from the local touch control.
B. Use the Participant settings from the MCU 5300 web interface.
C. Use the Call settings from the remote control.
D. Use the Call Control settings from the codec web interface.
E. Use the Conference settings from the codec web interface.
Correct Answer: B,D
Management would like to set up a permanent recurring Cisco TelePresence meeting where the team would dial into to a preconfigured number. 210-065 dumps Which meeting type should be used?
A. scheduled conference
B. ad hoc conference
C. rendezvous conference
D. multiway conference
Correct Answer: C
A large company wants to procure video conference devices that allow multipoint conferences from C-Series and immersive endpoints that are registered to a Cisco VCS and Cisco Unified Communications Manager. Which two components meet the requirements of this company? (Choose two.)
A. Cisco TelePresence Multipoint Switch registered to Cisco VCS
B. Cisco C-Series endpoint with a multisite option key registered to Cisco VCS
C. Cisco TelePresence Server registered to Cisco VCS
D. Cisco C-Series endpoint with a multisite option key registered to Cisco Unified Communications Manager
E. Cisco TelePresence Multipoint Switch trunked to Cisco Unified Communications Manager
Correct Answer: C,E
A technician has installed and powered on a Cisco TelePresence MCU 5320 and is connected via the console port. 210-065 pdf The technician needs to determine the IP settings that were automatically assigned via DHCP. Which command should be entered?
B. show network eth0
D. help static
Correct Answer: C
A Cisco TelePresence VCS displays this alarm: “Root password is set to default.” 210-065 dumps How can this security warning be addressed?
A. Use the Cisco TelePresence VCS web user interface, choose Administration > User Settings, and change the root password.
B. Use SSH to log in to the Cisco TelePresence VCS as Administrator and issue the command xconfig root set passwd.
C. Use SSH to log in to the Cisco TelePresence VCS as Root, issue the command set password, and enter the new password when prompted.
D. Use SSH to log in to the Cisco TelePresence VCS as Root, issue the command passwd, and enter the new password when prompted.
E. Use the Cisco TelePresence VCS web user interface, choose Administration > System Settings, and change the root password.
Correct Answer: D
Reference: https://www.lead4pass.com/210-065.html dumps exam questions and answers.
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Description: When trying to place a call to our Support line (888-360-9639), people making the call from Skype are unable to get through. This is a known issue.
Scope: All calls initiated from Skype.
Work-around: Following these steps will allow you to reach us using a Skype connection:
1. Enter +118883609639 on dial-pad (Adding an extra 1 here before 1-888-360-9639)
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After the first call goes through successfully, you will be able to call with Skype by dialing the number as normal (1-888-360-9639).


I recently moved, so I decided to change my cell phone number so that the area code would be local. Today I received two phone calls from collection agencies, presumably for the person who used to have my new cell phone number. I hadn’t thought about the possibility of getting someone else’s old number, but I guess there are a limited number of numbers.
According to this article, a cell phone number may only be dormant for as few as 30 days before it is reissued! Also, if the old owner was subscribing to a text-messaging service, such as news flash updates, or daily haiku poems, the new phone may start receiving them.
So my advice is to never move out of your area code so you don’t have to change your cell phone number.


A team from the Institute for Print and Media Technology at Chemnitz University of Technology, Saxony, had been working on the project for just two and a half years when they managed to make a successful prototype.
The paper loudspeaker was made by printing several layers of a conductive organic polymer and a piezoactive layer which is an active element of most acoustic transducers onto a regular piece of paper.The paper is then fitted with a cable which is connected to a computer or MP3 player. Sounds are produced when the layers vibrate against each other and push out sound. The printable loudspeakers can produce up to 80 decibels which is about the same as a ringing telephone or alarm clock. Amaseing!
Researchers say the speakers are surprisingly robust and can be produced at a low-cost because of the mass printing possibilities of polymers. Dr. Georg Schmidt, senior researcher at pmTUC explained that, as polymers are cheap to make in big batches, the printable speaker could not only become a practical, cheaper alternative to normal speakers. That is as long as you don’t mind a slight lack of bass – the speakers cannot yet deliver heavy sounds when turned up to 11. Ok, so no thumping bass, but these researchers are thinking ahead. Printable electronics are expected to generate around $13 billion by 2016. In fact, a market research report says this printable electronics will see a compound annual growth rate of 29.4% over the next five years. And, even though it’s just a prototype, this printable loudspeaker creates a possibility for new applications.
The team in Chemnitz have high hopes for the printable speaker, which is highly flexible and even “produces a better sound when it is being bent” Schmidt said, but refrained from going into the complicated physics behind this. While the speaker could be a great alternative to regular speakers, the team are particularly interested in the idea of developing “intelligent packaging”. The speakers will be on display in Düsseldorf, at the “drupa” – an international print-media expo that takes place between May 3 and May 16.


As the Chief Inspector of the U.S. Marshals’ Office of Emergency Management Tactical Operations Division, Michael Pyo is in charge of three major programs — Mobile Command Centers, the Communications Center and the Explosive Detection Canine Program.
Pyo who has been with the service for 17 years was honored at the Director’s Honorary Awards Ceremony on Tuesday for his “tireless efforts and outstanding contributions” to the U.S. Marshals.
Last year, Pyo served as the project manager for the acquisition of two new mobile command centers — rolling offices equipped with satellite communications equipment that deploy anywhere — and in 2008, he oversaw the relocation of the communications center to a new facility in Springfield, Va.
Pyo oversees three mobile command centers in Oklahoma City, Okla., Pineville, La., and Springfield, Va.
The technology used in the mobile command centers needs to be updated consistently because it provides the backbone for communications after a natural disaster or other incident. The mobile unit also supports the radio communication abilities of local law enforcement officials.
“The infrastructure typically goes down, your cell service is not going to be up and running, so you have to rely on the satellite,” Pyo said.
The mobile command units also are deployed to other situations that require U.S. Marshal protection — most recently to the trial of Scott Roeder who was convicted of murdering abortion provider George Tiller.
“It’s not just a matter of parking a big truck in the bay area and leaving it, because you always want to make sure it’s always up and running,” said Pyo.


Airbus Ventures congratulates Qunnect, the leader in quantum internet technologies, for announcing its Series A funding of more than $8 million. The round was led by Airbus Ventures, with additional participation from Quantonation, SandboxAQ, NY Ventures, Impact Science Ventures and Motus Ventures.
Spearheaded by CEO Dr. Noel Goddard and founders Dr. Mehdi Namazi and Mael Flament, Qunnect is developing a quantum-safe network technology designed for scalable deployment on existing telecommunications fiber infrastructure. These new funds will be used to further develop its product suite, scale manufacturing and launch a multi-node R&D quantum network test bed to demonstrate entanglement distribution protocols. This network, connected to existing fiber optic cable in New York City, will be the first of its kind in the US.
Qunnect’s products, including an entangled photon source with unmatched compatibility with atomic devices and high-fidelity quantum memory, are key enablers for applications in quantum sensing and computing. The true value of Qunnect will be in the integration of these technologies, in a holistic suite to perform long-distance quantum communication protocols. These protocols remove the vulnerabilities of first-generation quantum key distribution systems, which are fundamentally limited in distance and require relay nodes to scale, creating security risks.
Most of the quantum networking technologies seen in the research community require extreme cooling and/or high vacuum support infrastructure. In contrast, Qunnect’s world-class solutions support real-world deployment and scalability, designed to operate at room temperature, rather than in fragile, climate-controlled laboratory environments.
In September 2021, the company commercialized the world’s first quantum memory, a critical component in enabling secure long-distance quantum communication protocols. Building on this achievement, once its first-generation product suite is complete in mid-2023, Qunnect will be ready to provide the first distributed entanglement network to the commercial market.


The In-car Audio System Market has evolved dramatically over the years, enhancing our driving experiences and transforming our vehicles into mobile concert halls. From AM radios to advanced infotainment systems, the evolution of in-car audio technology has been nothing short of astonishing. In this article, we will delve into the dynamics of the in-car audio system market, exploring its growth, innovations, and what the future holds for audio enthusiasts on wheels.
The Evolution of In-car Audio
In this section, we will take a nostalgic journey through the history of in-car audio systems, from the rudimentary beginnings to the sophisticated systems of today.
Key Players in the Market
We will examine the leading companies that dominate the in-car audio system market, their market share, and the innovations they bring to the table.
Types of In-car Audio Systems
From traditional car radios to cutting-edge surround sound systems, we will explore the various types of in-car audio systems available to consumers today.
Sound Quality and Performance
In this section, we will discuss the critical factors that determine sound quality in a car audio system and how technology is continually pushing the boundaries of audio excellence.
Integration with Smart Technology
The integration of in-car audio systems with smartphones and other smart devices has revolutionized the way we interact with our cars. We’ll discuss the seamless connectivity options available.
Trends and Innovations
Stay up-to-date with the latest trends and innovations in the in-car audio system market, from voice assistants to personalized audio profiles.
Car enthusiasts love to personalize their vehicles, and audio systems are no exception. Learn about the customization options available in the market.
As sustainability becomes increasingly important, we will explore how in-car audio system manufacturers are making strides in reducing their carbon footprint.
Market Growth and Projections
Get an insight into the growth of the in-car audio system market and projections for the coming years, including market size and potential challenges.
The Future of In-car Audio
What can we expect from in-car audio systems in the future? We’ll discuss emerging technologies and their potential impact on our driving experiences.
In conclusion, the in-car audio system market is on a continuous journey of innovation and improvement. As technology advances and consumer demands evolve, we can anticipate even more exciting developments in the world of in-car audio.
- Are in-car audio systems only for music? No, modern in-car audio systems offer a wide range of features, including navigation, hands-free calling, and even internet connectivity.
- How can I improve the sound quality of my in-car audio system? Upgrading your speakers, adding a subwoofer, or soundproofing your car can significantly enhance the sound quality.
- What is the role of digital signal processing in car audio systems? Digital signal processing (DSP) is used to fine-tune audio signals, ensuring optimal sound quality in various driving conditions.
- Are wireless audio connections reliable in cars? Yes, Bluetooth and other wireless technologies have become very reliable for audio streaming in vehicles.
- Can I install a high-end in-car audio system in my older vehicle? Yes, it’s possible to retrofit your older vehicle with a high-quality in-car audio system, but it may require some customization.


Reflector Antennas (Synthesis Lectures on Antennas)
- September 7, 2007
- 2.39 MB
- 4816 Downloads
Morgan & Claypool Publishers
Communications engineering / telecommunications, Engineering - Electrical & Electronic, Technology & Engineering, Science/Mathem
|Contributions||Constantine Balanis (Editor)|
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Handbook of Reflector Antennas and Feed Systems: Volume 1 - Theory and Design of Reflectors (Artech House Antennas and Propagation Library) [Satish K Sharma, Satish K Sharma, Sudhakar Rao, Lotfollah Shafai] on *FREE* shipping on Reflector Antennas book offers.
Handbook of Reflector Antennas and Feed Systems: Volume 1 - Theory and Design of Reflectors (Artech House Antennas 5/5(1). The intent of this book volume Reflector Antennas book to provide practical applications and design information on reflector antennas used for several communications systems.
This book covers recent developments of reflector antennas used for satellite communications, terrestrial communications, and 5/5(2).
Reflector Antennas Paperback – Decem by A.W. Love (Editor) See all 4 formats and editions Hide other formats and editions. Price New from Used from Hardcover "Please retry" $ $ $ Paperback "Please retry" $ Format: Paperback.
Handbook of Reflector Antennas and Feed Systems: Volume 2 - Feed Systems (Artech House Antennas and Propagation Library) [Lotfollah Shafai, Lotfollah Shafai, Satish K Sharma, Sudhakar Rao] on *FREE* shipping on qualifying offers. Handbook of Reflector Antennas and Feed Systems: Volume 2 - Feed Systems (Artech House Antennas and Propagation Library)5/5(2).
This most excellent book presents a detailed discussion on the theory and design of the different aspects of reflector antennas, which will serve as a handy reference book for the interested readers.
In other words, interested readers will be able to find most of the significant reference material related to reflector antennas, feed systems, and their applications.5/5(1).
This is the first truly comprehensive and most up-to-date handbook available on modern reflector antennas and feed sources for diversified space and ground applications.
There has never been such an all-encompassing reflector handbook in print, and no currently available title offers coverage of such recent research developments.
Description Reflector Antennas (Synthesis Lectures on Antennas) FB2
Analysis of Reflector Antennas provides information pertinent to the analysis of reflector-antenna systems. This book provides an understanding of how design data have been and can be derived.
Organized into four chapters, this book begins with an overview of the history of focusing reflector-antenna systems characterized by a highly variable level of general interest.
Reinaldo Perez, in Wireless Communications Design Handbook, Reflector antennas have been in use since World War II. Their main purpose is to converge the energy in a given direction, and therefore they tend to provide higher directivities.
Download Antennas By John D. Kraus – This text is for the course on antennas offered to the senior/graduate level by most electrical engineering departments.
It will also appeal to practicing engineers working on antenna development. The text explains both the basic theory of antennas and its application to practical designs. The success of the three previous editions of Practical Antenna Handbook has been most gratifying. Clerks in radio stores told me that this book was outselling other titles They confirmed that the types of people who buy the book meet the profile above.
It was with surprise and delight that I noted that clerks in one radio. Analysis of Reflector Antennas provides information pertinent to the analysis of reflector-antenna systems.
This book provides an understanding of how design data have been and can be derived. Organized into four chapters, this book begins with an overview of the history of focusing reflector-antenna systems characterized by a highly variable Book Edition: 1. An antenna reflector is a device that reflects electromagnetic waves.
Antenna reflectors can exist as a standalone device for redirecting radio frequency (RF) energy, or can be integrated as part of an antenna assembly. Standalone reflectors. Types of parabolic antennas.
Corner reflector part of a UHF television antenna. Antenna Reflector basics and types-Plane,Corner,Parabolic. This page on Antenna reflector basics and types cover different reflector antennas viz. plane reflector, corner reflector and parabolic reflector. The equations of these reflector antennas are also mentioned.
Plane Reflector Antenna. The figure-1 depicts plane reflector antenna type. Handbook of Reflector Antennas and Feed Systems Volume 3: Applications of Reflectors Sudhakar Rao, Sudhakar Rao, Lotfollah Shafai, Satish K. Sharma This is the first truly comprehensive and most up-to-date handbook available on modern reflector antennas and feed sources for diversified space and ground applications.
Lens antennas with their quasi-optical characteristics, also have low loss, particularly at near millimeter and submillimeter wavelengths where they have particular advantages.
This book systematically conducts advanced and up-to-date treatment of lens antennas. The aperture, gain, and efficiency of an antenna were all defined in Chapter 1 for antennas in general.
The aperture A of a dish antenna is the area of the reflector as seen by a passing radio wave: A = πr2 where r is the radius, half of the diameter of the dish. If we replace a dish antenna with a much larger one, the greater aperture of the File Size: KB.
Throughout the book numerous illustrative design examples including numerical and experimental results are provided. The reflectarray antenna is a hybrid design combining many of the best features of reflector antennas and printed arrays, in a low-profile, low-mass, highly cost-effective design.
Additional Physical Format: Online version: Reflector antennas. New York: IEEE Press, © (OCoLC) Document Type: Book: All Authors / Contributors.
A corner reflector antenna is a type of directional antenna used at VHF and UHF frequencies. It was invented by John D.
Kraus in It consists of a dipole driven element mounted in front of two flat rectangular reflecting screens joined at an angle, usually 90°. The intent of this book volume is to provide practical applications and design information on reflector antennas used for several communications systems.
This book covers recent developments of reflector antennas used for satellite communications, terrestrial communications, and remote sensing applications. Casse grain is another type of feed given to the reflector antenna. In this type, the feed is located at the vertex of the paraboloid, unlike in the parabolic reflector.
A convex shaped reflector, which acts as a hyperboloid is placed opposite to the feed of the antenna. It is also known as secondary hyperboloid reflector or sub-reflector. In he moved to the Antenna Department at Ericsson where he was involved with broadband polarizers and twist reflectors, stripline and waveguide slot arrays, and phased array antenna systems.
He is responsible for the introduction of new antenna technology and systems, internal R& D projects, and internal courses relating to s: 1.
The most well-known reflector antenna is the parabolic reflector antenna, commonly known as a satellite dish antenna. Examples of this dish antenna are shown in the following Figures.
The "big dish" antenna of Stanford University. A random direcTV dish antenna on a roof. Parabolic reflectors typically have a very high gain ( dB is common. antennas, a lower cost, similar gain, light weight antenna can be produced to attract more consumers.
The goal of this project is to design and build high gain, low cost, low profile antenna that can beFile Size: 2MB. Antenna Fundamentals Introduction, Radiation mechanism - Single wire, 2 wire, Dipoles, Current distribution on a thin wire antenna.
Antenna parameters - Radiation patterns, Patterns in principal planes, Main lobe and side lobes, Beamwidths, Beam area, Radiation intensity, Beam efficiency, Directivity, Gain and resolution, Antenna apertures, Aperture efficiency, Effective height related /5(10).
a flat reflector such as used in a Short backfire antenna or Sector antenna. a corner reflector used in UHF television antennas.
Details Reflector Antennas (Synthesis Lectures on Antennas) PDF
a cylindrical reflector as used in Cantenna. Design criteria. Parameters that can directly influence the performance of an antenna with integrated reflector: Dimensions of the reflector (Big ugly dish versus small. Part 1 — Practical Antennas. Antenna Basics - 25 September 2.
Electromagnetic Horn Antennas - March 3. Metal-plate Lens Antennas - April 4. Parabolic Dish Antennas - March 5. Offset-fed Parabolic Dishes - 29 April Appendix 5A - Common Offset Dishes - October 6. Feeds for Parabolic Dish Antennas - in progress. The parabolic reflector antenna theory also shows the emanating beam will tend to be parallel.
Download Reflector Antennas (Synthesis Lectures on Antennas) FB2
Parabolic antenna focal length. One important element of the parabolic reflector antenna theory is its focal length. To ensure that the antenna operates correctly, it is necessary to ensure that the radiating element is placed at the focal point.
Book:Antennas rf. Jump to navigation Jump to search. WARNING. The in-house PDF Download as PDF. This is a Wikipedia book, a collection of Wikipedia articles that can be easily saved, imported by an external electronic rendering service, and ordered Corner reflector antenna Turnstile antenna Patch antenna T-antenna Rubber ducky antenna.
Get this from a library. Handbook of reflector antennas and feed systems. [Sudhakar Rao, (Aerospace engineer); Lotfollah Shafai; Satish Sharma;] -- This is the first truly comprehensive and most up-to-date handbook available on modern reflector antennas and feed sources for diversified space and ground applications.
There has never been such an. A reflectarray antenna (or just reflectarray) consists of an array of unit cells, illuminated by a feeding antenna (source of electromagnetic waves).
The feeding antenna is usually a unit cells are usually backed by a ground plane, and the incident wave reflects off them towards the direction of the beam.A phase distribution of concentric rings is applied to focus the wavefronts from.
Parabolic Reflector Antennas. Click here to go to our main page on antenna design. This rule is attributed to Robert E. Collin, in his book, Foundations for Microwave Engineering.
Click here to go to our page on recommended books on all microwave engineering topics. Robert Collin wrote some outstanding textbooks back in the s and s.DIY Antenna with reflector.
My wife and I finally decided to cut the cord and paid off DirecTV to go away. To that end, we bought an antenna and tried to pull in the basic stations (NBC, CBS, ABC, FOX and PBS). Being fairly far out we went ahead and paid a bit more for one which advertised that it would pickup signals over 50 miles out.
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