The internet has become an essential part of our daily lives, and with the increasing number of devices connected to it, the demand for IP addresses is higher than ever. IPv4, the most widely used protocol for internet communication, has a limited number of addresses available. As a result, the world is facing an IPv4 shortage. But don’t worry! In this article, you’ll learn some tips to avoid the IPv4 shortage and ensure your business stays connected.
Understand the IPv4 Shortage
Before diving into the tips, it’s essential to understand the IPv4 shortage. IPv4 uses 32-bit addresses, which means there are approximately 4.3 billion possible addresses. However, with the increasing number of devices connected to the internet, these addresses are running out. This shortage has led to the development of IPv6, which uses 128-bit addresses and provides a virtually unlimited number of IP addresses. However, the transition to IPv6 has been slow, and many businesses still rely on IPv4 addresses.
Consider IPv6 Adoption
One of the best ways to avoid the IPv4 shortage is to adopt IPv6. As mentioned earlier, IPv6 provides a virtually unlimited number of IP addresses, ensuring that your business will not face any shortage issues in the future. Additionally, IPv6 offers improved performance, security, and efficiency compared to IPv4. To adopt IPv6, you need to ensure that your network infrastructure, devices, and applications are compatible with the new protocol. You can also use dual-stack technology, which allows your network to run both IPv4 and IPv6 simultaneously.
Buy IPv4 Addresses from a Trusted Broker
If your business still relies on IPv4 addresses, you can avoid the shortage by purchasing additional IPv4 addresses from a trusted broker like prefixbroker.com. By visiting Prefixbroker.com, you can find a wide range of IPv4 address blocks available for purchase. Buying IPv4 addresses from a trusted broker ensures that you get legitimate and clean IP addresses, which are essential for maintaining your business’s online reputation and avoiding potential blacklisting.
Optimize Your Existing IPv4 Address Space
Another way to avoid the IPv4 shortage is to optimize your existing IPv4 address space. You can do this by:
1. Implementing Network Address Translation (NAT): NAT allows multiple devices to share a single public IPv4 address, reducing the number of addresses your business needs.
2. Using private IP addresses: Private IP addresses are reserved for use within a private network and are not routable on the internet. By using private IP addresses for your internal devices, you can save public IPv4 addresses for devices that need internet access.
3. Subnetting: Subnetting involves dividing your IP address space into smaller, more manageable segments. This can help you use your existing IPv4 addresses more efficiently and reduce the need for additional addresses.
4. Reclaiming unused IP addresses: Regularly audit your IP address usage and reclaim any unused addresses. This can help you free up valuable IPv4 address space and reduce the need for additional addresses.
In conclusion, the IPv4 shortage is a real concern for businesses that rely on internet connectivity. By understanding the issue, considering IPv6 adoption, buying IPv4 addresses from a trusted broker, and optimizing your existing IPv4 address space, you can avoid the shortage and ensure your business stays connected.


Smart Phone Screen Magnifier For All Phones Screen Amplifiers Projector.
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Regular price Rs.320.00
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1. This is a mobile phone holder for eye protection, which can enlarge the screen of the mobile phone.
2. This product is suitable for mobile phone models under 7 inch.
3. Designed according to ergonomic principles, fine-tuning the operating distance can meet the needs of different users.
4. Abandoning the injection molding technology, it is made of ordinary lenses, and the top Fresnel lens is produced by pressing technology to make the picture clearer.
5. The combination of fashion and scientific and technological innovation can create a smooth product technical appearance, which is more in line with the aesthetic needs of modern people.


Amaya Freebuds Sport True Wireless Earbuds
Non-in-ear, 3D sound effect, stable for sport
The Amaya Freebuds Sport are a pair of wireless earphones that offer great value for money. They feature Bluetooth 5.3 connectivity, IPX4 water resistance, and up to 48 hours of playback time on a single charge.
With their comfortable design and snug fit, the Amaya Freebuds Sport are perfect for listening to music, podcasts, or audiobooks on the go. They also feature touch controls so you can easily adjust the volume, skip tracks, or answer calls without having to take your phone out of your pocket.
Here are some of the key features of the Amaya Freebuds Sport:
- Bluetooth 5.3 connectivity for a stable and reliable connection
- IPX4 water resistance for sweat and splash resistance
- Up to 48 hours of playback time on a single charge with 90 days stand-by time
- Touch controls for easy operation
- Built-in microphone for hands-free calling
- IPX5 Water resistance
If you are looking for a pair of wireless earphones that offer great sound quality, battery life, and features, the Amaya Freebuds Sport are a great option.
Here are some additional details about the Amaya Freebuds Sport:
- The earphones come with a charging case that provides an additional hours of playback time.
- The earphones are compatible with all smartphones and tablets that support Bluetooth 5.3.
- The earphones come with a 12-month warranty.


Desktop and embedded software development
Windows, Mac, QNX, iOS, web and embedded user interfaces
Analogue and digital electronics design
Schematic capture and PCB layout
Wired communications - RS-232, RS-485, Ethernet, MVB Wireless communications - Bluetooth, Wi-Fi, Cellular
Alonyx provided software development and electronics design for a handheld test device to power a multi-function railway sensor and enable installers and maintainers to view the outputs of the sensor by the side of the track.
Alonyx provided system engineering support, software development and electronics design in the development of a new range of on-train equipment.
Two interconnected units were developed, one for installation in the cab close to all the necessary input and output signals and driver indications, the other under the rear of the vehicle where the system control was required. These were. subjected to EMC and environmental testing then over 120 systems were delivered for installation on a fleet of long distance inter-city trains. In 2019 not only did these systems win the Rail Business Awards in the Technical Innovation Excellence category, but IMI Norgren exhibited the next generation of the system on their stand at Railtex!
Alonyx developed the software embedded in a stylish self-cleaning fish tank. Adopting our preferred incremental approach saw us start with a commercially available development board, adding temperature sensors, heating control, lighting control, a real-time clock and finally a user interface. The electronics module closely matched the development platform, minimising risk when migrating to the production system, and allowing the software development to be largely completed before the production hardware was ready.
Alonyx provide the software development for DB ESG Rail's WSPER test rig, a "hardware in the loop" test facility for train braking systems. A Windows PC runs the configuration, control and results analysis applications, whilst a number of PCs running the QNX real-time operating system are used to model the behaviour of a train to the system's control. National Instruments hardware is used to provide the interface to the system under test. A number of development cycles have been undertaken to improve the features offered to match the ever increasing sophistication of on-train equipment.
Some key facts about us:
- Established in the East Midlands in 2013
- Provide clients with access to our software and electronic systems product development expertise
- Extensive experience in developing asset condition monitoring and train control products for the rail industry
We love developing software and electronic systems, and look forward to helping you with your project.
We've used Macs, PCs, embedded microcontrollers, all sorts of communications layers from the humble RS-232 and RS-485 serial ports to ethernet, wi-fi, bluetooth, or mobile cellular systems such as GPRS/3G/4G.
The projects have ranged from handheld test and measurement devices for use in intriniscally safe environments to rack based systems hardened against life on-trains and around the railway.


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The Global System for Mobile Communications (GSM) is a second generation (2G) standard for mobile networks. In the early 1980s, a group was formed by the European Telecommunications Standards Institute (ETSI) to develop a digital mobile communication system.
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GSM Tutorial. GSM (Global System for Mobile communications) is an open, digital cellular technology used for transmitting mobile voice and data services. GSM differs from first generation wireless systems in that it uses digital technology and Time Division Multiple Access (TDMA) transmission methods.
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GSM (Global System for Mobile Communications, originally Groupe Spécial Mobile), is a standard developed by ETSI European Telecommunications Standards Institute. An independent, not-for-profit, standardization organization in the telecommunications industry in Europe, developing global telecommunications standards. to describe the protocols for second-generation (2G) digital cellular …
GSM (Global System for Mobile communications) is a standard developed by the European Telecommunications Standards Institute (ETSI) to describe the protocols for second-generation digital cellular networks used by mobile devices such as mobile phones and tablets. It was first deployed in Finland in December 1991. As of 2014, it has become the global standard for mobile communications ...
What is GSM (Global System for Mobile communication ...
GSM (Global System for Mobile communication) is a digital mobile network that is widely used by mobile phone users in Europe and other parts of the world. GSM uses a variation of time division multiple access and is the most widely used of the three digital wireless telephony technologies TDMA, GSM and code-division multiple access . GSM ...
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Dec 12, 2015 · The base stations (towers) used in mobile communication use two types of antennas. Rectangular Antenna - These antennas transmit signals from the base station to the mobile phone. The y are directional and in a normal implementation, every base s...
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BSC is connected to the Mobile Switching Center (MSC), which is a part of NSS. Figure shows the key functional elements in the GSM network architecture. 1. Mobile Station (MS) A mobile station communicates across the air interface with a base station transceiver in the same cell in which the mobile subscriber unit is located.
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In my homelab overview post, I briefly touch on how I use KVM VMs - mostly for work - on my NUC. I wanted to provide a little more detail on that setup, because it's not the normal out-of-the-box experience of KVM/libvirt on Ubuntu.
I manage my VMs with Virtual Machine Manager, a cross-platform desktop GUI for managing KVM VMs, their networks, and storage. By default, a NAT network is created - similar to Docker default networks, a DHCP server is run by the hypervisor which provides a separate subnet to the VMs and translates traffic in and out at the host level. This is fine for testing software or a new Linux distro, but I often need traffic from outside my network to reach my VMs. For this, you need to create a new network of the routed type. Routed networks still use DHCP by default, so there's no convenience lost, there are just a few extra setup steps to take after creating it. While there are libvirt tools to do this work via config files and the CLI, I find them completely incomprehensible - partly because the documentation is pretty poor. So I use virt-manager to set things up.
The virt-manager GUI provides a wizard to create new networks - access this from the Details window and Network tab of the hypervisor connection. Virt-manager can manage both local and remote hosts, so there are usually at least 2 connections listed in virt-manager; one for the local machine, and one for the remote hypervisor. Right-click the appropriate connection and go to Details to bring up that hypervisor's configuration.
My LAN is pretty flat, so I only have the NAT network and the single routed network, but you could set up any number of separate networks to provide additional segmentation if you want.
Router and DNS Setup
With the routed network in place, I then set a static route on my router to point the LAN clients on the top-level network to the NUC for the lab subnet. This lets me directly address the VMs connected to that network from my wider LAN.
Naturally I don't want to have to use these IP addresses when I'm interacting with the virtual services, so I also create Local DNS records in Pihole for both the wider LAN devices as well as the devices in the routed KVM network.
Maybe it's a bug, maybe I'm skipping a step, but for some reason, virt-manager doesn't actually configure the routing in the host OS for some reason. It's quite possible I do something wrong or unexpected, but as I said, the documentation is pretty poor, so just finding this rule that had to be set was quite a challenge - if you're aware of a better way to do this, please let me know. In order to allow traffic following the static route to actually reach the VMs, I have an iptables rule set up on the host to NAT the traffic through the bridge:
iptables -t nat -A POSTROUTING -s 192.168.100.0/24 -o eno1 -j MASQUERADE
I mentioned in the homelab post that I'll be doing a more-detailed post on my Caddy setup, but following on the DNS setup above, I also set up hosts in Caddy for anything in the VMs that needs to be fronted with a web server and LetsEncrypt certificate. I do use Pihole's local DNS to keep LAN traffic on the LAN in the cases where the VMs are exposed to the internet; there's no reason for my traffic to route all the way back out to Cloudflare when Caddy has a perfectly valid certificate on it anyway.
Unlike some of the rest of the homelab, I don't really have any projects planned for my KVM setup. I have sufficient compute and storage, and no need to set up more advanced network-level firewalling or VLANing in my architecture, so this part of the architecture is actually complete.


Since 2004, MARCOM Telecomms & Consulting (MARCOM), is involved in the field of Distributor to Product / Project Management and Marketing of broadband (xDSL) Customer Premises Equipment (CPE), conducting business with major South African and regional companies, as well as customising the overall product to individual customer requirements, such as software, firmware implementation on the product and specific customised packaging criteria. Whether, you the customer require a generic off the shelf product, or customised units reflecting the look and feel of your company profile, we are able to accommodate and cater for such requirements.
Our DSL CPE product portfolios of xDSL (ADSL, SHDSL) router / gateways pertain to the Residential and Business segments as well as its associated networking WiFi equipment. The modems range from the single user PC environment to WiFi router gateways for residential and business applications, as well as DSL VPN functionalities.
Of course our product portfolio strongly markets the VoIP concept and products, having also All-in-one solution in a box comprising ADSL, WiFi, VoIP functionalities. Naturally we also market the IP Telephony phones with SIP, MGCP, DECT functionalities. Our product portfolio doesn't just stop at the modem / router / gateway domain but also cover the Set Top Boxes (STB) with triple play functionality - Voice, Data and Video applications and now involved in Fixed Mobile Convergence (FMC) Broadband FEMTO.
We are also the official distributors for Technicolor, previously Thomson. With more than 95 years of experience in entertainment innovation, Technicolor serves an international base of entertainment, software, and gaming customers. The company is a leading provider of production, postproduction, and distribution services to content creators, network service providers and broadcasters.
Technicolor is the worlds largest film processor; the largest independent manufacturer and distributor of DVDs (including Blue-ray Disc) and a leading global supplier of set-top boxes and gateways. With this partnership, MARCOM Telecomms is moving into the next phase of Content Capitalisation were we can offer an End to End (E2E) approach on media services such as IPTV etc. to work seamlessly into our CPE product portfolio.


With ever growing capacity requirements generated by iPads and other tablet devices the time is right to move to the latest wireless network solutions. After an exhaustive process evaluating many products ICT Services have selected Meraki to deliver next generation wireless to Nottinghamshire schools.
One of the many great advantages of the Meraki solution is the removal of the wireless controller from school and the cloud based management of the devices by ICT services.
From the inbuilt remote support of all devices on your network to the 5 minute set up of guest wireless networks via web splash pages the solution will transform the way networks are utilised in schools. With the ability to also traffic shape internet bandwidth by devices and applications the benefits are huge.
The solution even doubles up as an integrated mdm solution for all your iPad, Android and Windows devices. So if you want to create a lock code for your tablets or make apps available to all your estate in one action then Meraki delivers that too.
With around 10 schools, both primary and secondary, already making the move within 2 days of the solution being made available we're expecting a rapid take up as school's continue to grow their tablet environments and require the functionality that Meraki can deliver.
ICT Services have secured some very special prices, based on the number of schools we support and are part of our procurement frameworks, which you simply won't find anywhere else. So let us know if you're interested and we'll get you up and running in no time.


M6 is internet radio platform with TFT display integrating IR/ FM/ DAB+/ BT/ CD/ USB/ Aux-in.
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Magic Systech was established in 2004.
Our major business is to provide WiFi-based audio solution that includes hardware, software, database and App.
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The engineering language comprises concepts, rules and structures for the specification of an ODP system from the engineering viewpoint.
An engineering specification defines the mechanisms and functions required to support distributed interaction between objects in an ODP system.
The engineering language contains the concepts of ITU-T Rec. X.902 | ISO/IEC 10746-2 and those defined here, subject to the rules of 8.2.
8.1.1 Basic engineering object: An engineering object that requires the support of a distributed infrastructure.
8.1.2 Cluster: A configuration of basic engineering objects forming a single unit for the purposes of deactivation, checkpointing, reactivation, recovery and migration.
NOTE - a segment of virtual memory containing objects is an example of a cluster.
8.1.3 Cluster manager: An engineering object which manages the basic engineering objects in a cluster.
8.1.4 Capsule: A configuration of engineering objects forming a single unit for the purpose of encapsulation of processing and storage.
NOTE - a virtual machine (e.g., a process) is an example of a capsule.
8.1.5 Capsule manager: An engineering object which manages the engineering objects in a capsule.
8.1.6 Nucleus: An engineering object which coordinates processing, storage and communications functions for use by other engineering objects within the node to which it belongs.
NOTE - an operating system (kernel) is an example of a nucleus.
8.1.7 Node: A configuration of engineering objects forming a single unit for the purpose of location in space, and which embodies a set of processing, storage and communication functions.
1 A computer and the software it supports (operating system and applications) is an example of a node.
2 A node may have internal structure which is not of concern in an engineering specification. Thus a node can be, for example, a parallel computer under the control of a single operating system.
8.1.8 Channel: A configuration of stubs, binders, protocol objects and interceptors providing a binding between a set of interfaces to basic engineering objects, through which interaction can occur.
NOTE - Bindings that require channels are referred to as distributed bindings in the engineering language; bindings between engineering objects that do not require channels (e.g., between engineering objects in the same cluster) are referred to as local bindings.
8.1.9 Stub: An engineering object in a channel, which interprets the interactions conveyed by the channel, and performs any necessary transformation or monitoring based on this interpretation.
NOTE - For example, a stub can perform marshalling of parameters into communications buffers, or the recording of activity for audit purposes.
8.1.10 Binder: An engineering object in a channel, which maintains a distributed binding between interacting basic engineering objects.
8.1.11 <x> Interceptor: An engineering object in a channel, placed at a boundary between <x> domains. An <x> interceptor
-- performs checks to enforce or monitor policies on permitted interactions between basic engineering objects in different domains;
-- performs transformations to mask differences in interpretation of data by basic engineering objects in different domains.
NOTE - an inter-subnetwork relay is an example of an interceptor.
8.1.12 Protocol object: An engineering object in a channel, which communicates with other protocol objects in the same channel to achieve interaction between basic engineering objects (possibly in different clusters, possibly in different capsules, possibly in different nodes).
8.1.13 Communications domain: A set of protocol objects capable of interworking.
8.1.14 Communication interface: An interface of a protocol object that can be bound to an interface of either an interceptor object or another protocol object at an interworking reference point.
8.1.15 Binding endpoint identifier: An identifier, in the naming context of a capsule, used by a basic engineering object to select one of the bindings in which it is involved, for the purpose of interaction.
1 A memory address (for a data structure representing an engineering interface) is an example of an binding endpoint identifier.
2 The same form of binding endpoint identifier can be used, whether the binding involved is either local or distributed.
8.1.16 Engineering interface reference: An identifier, in the context of an engineering interface reference management domain, for an engineering object interface that is available for distributed binding.
NOTE - an engineering interface reference is necessary to establish distributed bindings, and is distinct from the binding endpoint identifiers used by a basic engineering object for the purposes of interaction.
8.1.17 Engineering interface reference management domain: A set of nodes forming a naming domain for the purpose of assigning engineering interface references.
8.1.18 Engineering interface reference management policy: A set of permissions and prohibitions that govern the federation of engineering interface reference management domains.
8.1.19 Cluster template: An object template for a configuration of objects and any activity required to instantiate those objects and establish initial bindings.
8.1.20 Checkpoint: An object template derived from the state and structure of an engineering object that can be used to instantiate another engineering object, consistent with the state of the original object at the time of checkpointing.
8.1.21 Checkpointing: Creating a checkpoint. Checkpoints can only be created when the engineering object involved satisfies a pre-condition stated in a checkpointing policy.
8.1.22 Cluster checkpoint: A cluster template containing checkpoints of the basic engineering objects in a cluster.
8.1.23 Deactivation: Checkpointing a cluster, followed by deletion of the cluster.
8.1.24 Cloning: Instantiating a cluster from a cluster checkpoint.
8.1.25 Recovery: Cloning a cluster after cluster failure or deletion.
8.1.26 Reactivation: Cloning a cluster following its deactivation.
8.1.27 Migration: Moving a cluster to a different capsule.
8.2 Structuring rules
An engineering specification defines the infrastructure required to support functional distribution of an ODP system, by
-- identifying the ODP functions required to manage physical distribution, communication, processing and storage;
-- identifying the roles of different engineering objects supporting the ODP functions (for example the nucleus).
An engineering specification is expressed in terms of
-- a configuration of engineering objects, structured as clusters, capsule and nodes;
-- the activities that occur within those engineering objects;
-- the interactions of those engineering objects.
An engineering specification is constrained by the rules of the engineering language. These comprise
-- channel rules (8.2.1), interface reference rules (8.2.2), distributed binding rules (8.2.3) and relocation rules (8.2.4) for the provision of distribution transparent interaction among engineering objects;
-- cluster rules (8.2.5), capsule rules (8.2.6) and node rules (8.2.7) governing the configuration of engineering objects;
-- failure rules (8.2.9).
8.2.1 Channel rules
A channel supports distribution transparent interaction between engineering objects. This includes, for example,
-- operation execution between a client object and a server object;
-- a group of objects multicasting to another group of objects;
-- stream interactions involving multiple producer objects and multiple consumer objects.
Interaction between engineering objects entails the transfer of some or all of
-- engineering interface references;
-- cluster templates;
A channel is a configuration of stubs, binders, protocol objects and interceptors interconnecting a set of engineering objects. The configuration is an acyclic graph with stub objects at the outermost vertices as illustrated in figure 2 and figure 3. Each path through the graph between stub objects consists of, in sequence, either
-- a binder, a protocol object, a protocol object and a binder; or
-- a binder, a protocol object, an interceptor, a protocol object and a binder.
The behaviour of a channel with respect to channel configuration or quality of service management is controlled via control interfaces of stubs, binders, protocol objects and interceptors. Such control interfaces are optional.
1 Stubs, binders, protocol objects and interceptors in a channel can have (local or distributed) bindings to other engineering objects outside the channel providing, for example, relocation or coordination functions.
2 Depending upon the kind of transformation involved, an interceptor may be decomposed into stubs, binders, protocol objects and basic engineering objects, mirroring the channel structure.
Objects in a channel can themselves be basic engineering objects supported by channels.
Basic engineering objects which interact via channels are locally bound to stubs. In a channel, stubs provide the conversion of data carried by interactions. Stubs can apply controls and keep records (e.g., for security and accounting). Stubs can interact with engineering objects outside the channel (e.g., a security function) if required. A stub in a channel has an interface for use by the basic engineering object it supports and an interface for interaction with a binder. It can also have a control interface.
When interconnected stubs use different transfer syntaxes, there must be an interceptor in the path between them which can transform data from one syntax to the other.
A stub can be of one of the following forms:
a) specific to the basic engineering object interface instance to which it is bound;
b) specific to the interface type of the basic engineering object interface to which it is bound (therefore the stub may be shared between a number of channels of the same type);
c) generic (i.e., not specific to any single interface type); such stubs may be shared between a number of channels of different types.
1 In a) interactions between the engineering object and the stub only convey interaction data (e.g., operation names and parameters in the case of an invocation). The stub acts as a local proxy for other basic engineering objects bound to the channel.
2 In b) interactions must additionally include an identifier for the channel to be used.
3 In c) interactions must additionally include an identifier and type for the channel to be used, to enable the stub to ensure the interaction data are compatible with the channel type.
The binders in a channel manage the end-to-end integrity of that channel. When required, binders provide relocation transparency by monitoring communication failures and repairing broken distributed bindings. Binders in a channel can interact with engineering objects outside the channel to obtain additional data needed to perform their function (e.g., a relocator to obtain location data). A binder in a channel has at least an interface for interaction with a stub and one or more interfaces for interaction with protocol objects. A binder can have a control interface. If present, the control interface enables changes in the configuration of the channel and deletion of the channel.
22.214.171.124 Protocol objects
Protocol objects provide communication functions. Protocol objects can interact with engineering objects outside a channel (e.g., directory functions) to obtain the information they need. A protocol object has an interface for interaction with a binder and at least one communications interface for interaction with other protocol objects (via interceptors if required). A protocol object can have a control interface. When protocol objects in a channel are of different type, they require an interceptor which provides protocol conversion. All protocol objects in a communication domain can communicate directly using facilities of the communications domain (which fall outside the scope of this Reference Model).
At any given location in time, a protocol object is identified by its location in space, but different protocol objects can occupy the same location in space at different times (i.e., network addresses can be recycled). When protocol objects in a channel are of the same type, but in disjoint communications domains, naming conflicts are possible (e.g., names for communications interfaces might be ambiguous). In this circumstance, an interceptor is required to transform names exchanged in the process of establishing and maintaining the integrity of the channel.
An <x> interceptor in a channel stands at the boundary between <x> domains and provides checks and transformations on interactions that cross <x> domain boundaries. Depending upon the boundary crossed, interceptors require different information to perform their task. Some interceptors will need to know the signature types of the basic engineering object interfaces bound to the channel in which the interceptor is located so that they can interpret interactions supported by the channel. An interceptor has at least two communication interfaces. It can have a control interface.
8.2.2 Interface reference rules
For the purpose of distributed binding, engineering interfaces are located in space and time by engineering interface references. Engineering interface references are defined relative to an engineering interface reference management domain which determines policy for the content, allocation, tracking and validation of engineering interface references within that domain. An engineering interface reference management domain consists of a set of nodes. Engineering interface reference domains can be federated if their engineering interface reference management policies do not conflict.
An engineering interface reference contains information which enables bindings to be established to engineering object interfaces. This information both enables nucleus objects to create channels and also enables binders within channels to maintain a distributed binding between interconnected engineering objects. The information within an engineering interface reference can take the form of
-- identifiers for interfaces giving access to such data;
-- a combination of data and identifiers.
The data necessary for binding can include any or all of the following items:
-- the interface type of the referenced interface;
-- a channel template describing the interceptors, protocol objects, binders and stubs that can be selected when configuring a channel to support the distributed binding;
-- the location in space and time (e.g., a network address) of the communication interfaces at which the binding process can be initiated;
-- information to enable the detection and repair of distributed bindings invalidated by engineering object relocation.
An interface reference management domain can be divided into subdomains. In this case interface references within the domain are organized as a set of alternative sets of information, one for each subdomain in which binding is to be enabled.
1 If the nucleus supporting the engineering interface supports different protocols, binding processes and transfer syntaxes, the engineering interface reference will indicate the valid combinations that can be selected in any particular distributed binding; different bindings might make different selections.
2 This Reference Model does not prescribe the method by which a channel template and the location in space and time of related interfaces are derived from an engineering interface reference.
Engineering interface references are allocated by nuclei, at interfaces supporting the node management function (see 12.1.3). Engineering interface references are tracked by the engineering interface reference tracking function (see 13.9) for the purposes of detecting engineering interfaces which are no longer referenced. Policy for rebinding to engineering object interfaces which have been relocated, and updated engineering interface references for engineering interfaces which have been relocated, are recorded by the relocation function (see 14.3). These three functions (node management, engineering interface reference tracking and relocation) may be coordinated by use of a shared information organization function (see 14.2).
Engineering interface references are unambiguous in the naming context of an engineering interface reference management domain. To achieve this unambiguity, the nodes within the engineering interface reference management domain must allocate engineering interface references in a coordinated way. Engineering interfaces must be allocated in a manner which prevents an engineering interface reference from referencing the wrong interface, even in the presence of failures and interface relocation. At worst an interface reference will refer to an interface which does not exist (e.g., immediately after failure of the engineering object supporting the interface).
NOTE - In ODP systems in which most interfaces do not change location, the management of interface references can be optimized: the nucleus can allocate engineering interface references autonomously; the channel type and communications interface identifier associated with the interface can be stored and transmitted within the engineering interface reference; the relocation function can be used to validate and update engineering interface references for interfaces that have been relocated.
Before issuing an engineering interface reference, the nucleus constructs a channel template which defines a configuration of stub, binder and protocol objects suitable to support interactions in the interface. In addition the nucleus establishes sufficient local structure to make binding to the interface possible, and associates the template and the local structure with a communications interface. The engineering interface reference makes this information available.
An interceptor that stands on a boundary between engineering interface reference management domains maintains mappings between engineering interface references in those domains. When an engineering interface reference or a cluster template containing engineering interface references crosses an engineering interface reference domain boundary, the engineering interface references involved must be transformed so as to be valid in the new domain.
Media interchange of engineering interface references from one interface reference management domains to another is only possible when there is a defined procedure for mapping the references to avoid ambiguity.
8.2.3 Distributed binding rules
Establishing a channel requires the creation of appropriate stubs, binders, protocol objects and interceptors. Channel establishment can be initiated by any engineering object. It is provided by each nucleus as a function of its node management interface. Distributed binding involves interaction with the nuclei of the nodes at which the interfaces to be bound are located. Channel establishment is parameterized by a channel template and a set of interface references each assigned to a particular role in the channel template. The channel template must be compatible with the channel types nominated by the engineering interface references for the interfaces to be bound. The nucleus for each object to be bound creates a configuration of stubs, binders and protocol objects at its node to support the interfaces of that object being bound. This includes configuration of their control interfaces. The protocol objects that support the channel are connected (possibly via interceptors) at their communication interfaces. The selection and configuration of stubs, binders, protocol objects and interceptors is determined by the channel template and channel types of the interface references involved. Each basic engineering object bound by the channel is assigned a binding endpoint identifier for each interface it has to the channel. Basic engineering objects use binding endpoint identifiers to nominate at which of their interfaces a distributed interaction is to occur.
1 Channels can be established by any engineering object irrespective of whether or not the object has an interface that is to be bound by the channel.
2 A basic engineering object initiating a distributed binding requires a set of interface references. These may be obtained in any of the following ways: (a) on initialization of the object; (b) by interaction between the initiating object and the nucleus as part of the instantiation of the initiating object's interfaces; (c) through some chain of interactions with the other objects concerned (e.g., by parameter passing or trading).
3 A channel template can contain alternative configurations to be applied in selected circumstances. For example if communication paths are insecure, encrypting stubs might be required.
8.2.4 Relocation rules
Engineering objects can be relocated as a result of
-- reactivation and deactivation;
-- checkpointing and recovery;
-- communications domain management functions (e.g., changing a communication interface identifier).
1 A communications interface may have its identifier changed as a consequence of changing the network address of a node.
2 When channels are re-established, stubs, binders and protocol objects might be used which are different to those used prior to relocation. Thus an identifier for a communications interface is not necessarily sufficient to identify an engineering object interface.
Relocation can cause channels to fail and can invalidate engineering interface references. Failed channels can be repaired if the activity which changes the location of the engineering object interface notifies the relocation function appropriately (see 14.3).
The binders in a channel detect when relocation has invalidated the channel. Either the binders collaborate to correct the mapping between engineering interface references and the channel structure (i.e., relocation transparency is required -- see 16.6), or the channel fails. When relocation transparency is required the information available through the engineering interface reference enables the binders to use the relocation function to determine the new locations of the basic engineering objects involved.
8.2.5 Cluster rules
A cluster contains a set of basic engineering objects, associated with a cluster manager. Each member of a cluster can have an interface supporting the object management function. Each such object management interface is bound to the cluster's cluster manager. A basic engineering object in a cluster is always bound to its nucleus, at an interface providing the node management function and to its cluster manager. In addition, a basic engineering object in a cluster can be bound to other basic engineering objects in the same cluster, or in other clusters. Each cluster manager in a capsule is bound to the capsule manager for that capsule. This structure is illustrated in figure 4.
A cluster is always contained in a single capsule. A cluster is responsible for its own security, but can be assisted by security functions. Any assisting security function must either be provided by an object in the same capsule as that cluster, or be accessed by secure interactions if it is outside the capsule. Engineering objects in the same cluster can interact using a local binding within the cluster, or using a distributed binding supported by a channel. Engineering objects in different clusters interact using distributed bindings supported by channels.
1 Interactions that are at perceptual or interchange reference points are not precluded.
2 Although no channel is needed to support local bindings between objects in the same cluster, the identifier used to perform invocations is of the same kind as is used between engineering objects in different clusters, and is still called a binding endpoint identifier.
Cluster instantiation (including cloning as a special case) is performed by a capsule manager.
If the template is a cluster checkpoint, the instantiation (i.e., cloning) enables the new cluster to act as a substitute for the original cluster from which the cluster template was derived. When required for distribution transparency reasons, the cloning process includes re-establishing any distributed bindings that were held by the original cluster.
A cluster has an associated cluster manager. The cluster manager provides the cluster management function. The cluster manager embodies the management policy for the engineering objects in its cluster. The cluster management policy might lead the cluster manager to interact with other ODP functions to complete cluster management activities.
A cluster manager assists its capsule manager in the management of the engineering interface references of objects. This may require access to the engineering interface reference tracking function.
8.2.6 Capsule rules
A capsule consists of
-- cluster managers, one for each cluster in the capsule;
-- a capsule manager to which each of the cluster managers in the capsule is bound.
Stubs, binders and protocol objects for a channel bound to an interface of a basic engineering object within a cluster in a capsule can be included within that capsule. All the engineering objects in a capsule are bound to the same node management interface. Engineering objects in other capsules are bound to different node management interfaces. A capsule is contained within a node. A capsule has a capsule manager. The capsule manager is bound, at an interface providing the cluster management function, to each cluster manager in the capsule.This structure is illustrated in figure 5 (the figure abstracts out details of the nucleus).
Capsule instantiation is performed by the nucleus using a capsule template which specifies the initial configuration of engineering objects in the capsule, including clusters, cluster managers, stubs, binders, protocols and a capsule manager.
A capsule is a naming context for binding endpoint identifiers. The Reference Model does not require that such identifiers be valid in any larger context. Engineering interface references are used to communicate knowledge of engineering object interfaces between capsules (for the purposes of binding).
The capsule manager embodies the management policy for the clusters in its capsule. The capsule management policy might lead the capsule manager to interact with other functions to complete capsule management activities. The capsule manager has an interface providing the capsule management function. The the structures supporting interaction between cluster managers, capsule managers and the nucleus within a node are a matter of implementation detail outside the scope of this Reference Model.
8.2.7 Node rules
A node consists of one nucleus and a set of capsules. All of the engineering objects in a node share common processing, storage and communication functions.
A node is a member of one or more engineering interface reference management domains.
The nucleus provides a set of node management interfaces, one to each capsule within the node.
The structure of a node is illustrated in figure 6.
The procedure for node instantiation is outside the scope of this Reference Model: it must result in
-- introduction of the node's nucleus and its associated processing, storage and communications functions, including introduction of node management functions to enable distributed binding of engineering interface references;
-- introduction of any trading function needed by the instantiation process;
-- instantiation of any channels required as part of the initial configuration of the node (e.g., to supporting engineering objects such as a relocator).
The set of protocol objects introduced during node instantiation determine the initial set of communication domains to which the node belongs.The nucleus provides the node management function and embodies a node management policy. This policy might lead the nucleus to interact with other ODP functions to complete node management activities. A capsule is the basic unit for the application of node management policy; although an individual object can use the node management function, it is subject to the policies applicable to its capsule. Distinct capsules can be subject to different node management policies.
8.2.8 Application management rules
The management of the lifecycle (creation, migration, deactivation, reactivation, checkpointing, failure, recovery and deletion) of coordinated sets of clusters is driven by application-specific management policies. Application management policies can apply to individual clusters or to coordinated sets of clusters. A set of managed clusters form an application management domain. Applications management policy can be implemented by applications-specific management functions which effect changes using the mechanisms provided by the coordination and management functions defined in this reference model, e.g., the cluster management function.
Where appropriate (i.e., depending upon which distribution transparencies apply), application-specific management functions can receive notifications of significant events affecting the clusters they manage and takes action in response to those notifications. For example binding failure reports can lead to reactivation of a cluster, or excessive workload reports can lead to migration of clusters. Requests and notifications relating to one cluster in an application management domain can lead to application-specific management functions initiating lifecycle actions on other clusters in the domain.
The specifics of application domain management are beyond the scope of this Reference Model.
8.2.9 Failure rules
Failures can be categorized as involving clusters, capsules, nodes or communications domains. The analysis of failures is based on the fact that
-- a failure localized to a cluster can be detected by its cluster manager;
-- a failure localized to a capsule can be detected by its capsule manager;
-- the failure of a node may be detected by protocol objects at other nodes to which it is interconnected.
-- the failure of a communications domain may be detected by protocol objects in other communication domains to which it is interconnected.
NOTE - There is an inherent ambiguity in communication systems which may prevent a protocol object from distinguishing between communication failure and remote node failure.
8.3 Conformance and reference points
There is a programmatic reference point at an interaction point between a cluster manager and a basic engineering object.
There is a programmatic reference point at an interaction point between an engineering object and a nucleus.
There is a programmatic reference point at an interaction point between basic engineering objects.
There can be a perceptual or an interchange reference point at an interface of a basic engineering object.
Where interaction between basic engineering objects is provided by a channel, then, for each basic engineering object involved, there is a programmatic reference point at the interaction points between those objects and the corresponding stubs in the channel.
Within the configuration of objects that comprise a channel, there is a programmatic reference point at each of the following interaction points within the channel:
-- between stubs (abstracting the binders, protocol objects and interceptors in the channel between the stubs);
-- between stubs and binders;
-- between binders (abstracting the protocol objects and interceptors in the channel between the binders);
-- between binders and protocol objects
-- between protocol objects and other protocol objects within the same node (abstracting the interceptors, if any, between the protocol objects);
and there is an interworking reference point at any interaction point between protocol objects and other protocol objects or interceptors in different nodes.
Control interfaces of stubs, binders, protocol objects and interceptors are programmatic reference points.
Where engineering objects within a channel interact with other engineering objects (either within that channel or outside that channel) via interfaces which are not within that channel, then the reference points applicable to such interfaces are determined by the recursive application of these rules.
By defining conformance at the interworking reference points, interworking of systems is made possible.
By defining conformance at the programmatic reference points, portability of engineering objects between systems is made possible.
Conformance of individual engineering objects at the programmatic reference points does not itself guarantee that the engineering object will be portable to all systems or will interwork with matching engineering objects bound to other nuclei.
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In the ever-evolving landscape of technology, Computer networks (wireless-wired) play a pivotal role in connecting devices and facilitating communication. Whether it’s the seamless exchange of information wirelessly or through traditional wired connections, understanding the fundamental concepts of overview of Computer networks (wireless-wired) is crucial. This article will delve into the basic concepts, common components, and overview of Computer networks (wireless-wired), with a focus on both wired and wireless communication.
Overview of Computer networks (wireless-wired)
In the intricate tapestry of the digital age, the overview of Computer networks (wireless-wired) serves as the connective threads weaving together a multitude of devices and systems. These networks, encompassing both wired and wireless technologies, form the backbone of modern communication and information exchange. Let’s delve deeper into the expansive realm of overview of Computer networks (wireless-wired), exploring their overarching importance, types, and the fundamental concepts that govern their functionality.
The Significance of Computer networks (wireless-wired)
In an era characterized by the relentless pursuit of connectivity and information sharing, overview of Computer networks (wireless-wired) play a pivotal role in shaping the way we interact with technology. These networks enable seamless communication between devices, empower collaborative efforts, and facilitate the efficient exchange of data on a global scale. Whether it’s the transmission of critical business information, the streaming of multimedia content, or the interconnection of smart devices in the Internet of Things (IoT), overview of Computer networks (wireless-wired) form the lifelines of the digital world.
Types of Computer networks (wireless-wired)
1. Wired Networks:
Wired networks rely on physical infrastructure, using cables to establish connections between devices. Ethernet and fiber optic cables are common mediums in wired networks, providing reliable and high-speed data transmission. These networks are often preferred in scenarios where stability and security are paramount, such as in corporate environments.
2. Wireless Networks:
Contrastingly, wireless networks leverage radio waves for data transmission, eliminating the need for physical cables. Wi-Fi technology, a prime example of wireless connectivity, has revolutionized how we access the internet, enabling mobility and flexibility. Wireless networks are prevalent in homes, public spaces, and emerging technologies like 5G, fostering a world of interconnected, untethered devices.
Fundamental Concepts of Computer networks (wireless-wired)
a. Communication Protocols:
At the heart of every computer network are communication protocols. These protocols define the rules and conventions governing how data is transmitted and received across the network. The OSI model, with its layered approach, provides a framework for understanding the intricacies of these protocols, guiding communication from the physical hardware to the software applications.
b. Network Topologies:
Network topologies dictate the arrangement of devices within a network. Whether it’s a centralized star topology, a decentralized mesh topology, or a linear bus topology, the choice of topology impacts factors such as scalability, fault tolerance, and ease of maintenance.
c. Security Measures:
As the digital landscape expands, ensuring the security of information traversing networks becomes paramount. Network security involves implementing measures to safeguard against cyber threats, unauthorized access, and data breaches. Concepts like encryption, firewalls, and intrusion detection systems play crucial roles in fortifying network defenses.
d. Data Transmission Media:
Understanding the types of transmission media is essential in network design. Guided media, including traditional cables, and unguided media, like wireless signals, each have their advantages and considerations. Factors such as cost, reliability, and security influence the selection of the most suitable transmission medium for a given scenario.
Elmadrasah.com EMSAT Courses: Nurturing Network Proficiency
In the pursuit of knowledge and readiness for the EmSAT Achieve Computer Science test, Elmadrasah.com emerges as a guiding light. The EMSAT courses offered by Elmadrasah.com comprehensively cover the content areas outlined in the EmSAT Achieve Computer Science test specifications. From computing systems and network theory to problem-solving through programming practices, the courses are tailored to equip students with the skills and knowledge needed to excel in the ever-evolving landscape of computer science.
In the grand tapestry of technology, Computer networks (wireless-wired) serve as the intricate threads connecting the digital world. Understanding the fundamental concepts, types, and significance of these networks is not only essential for acing exams like EmSAT Achieve Computer Science but also for navigating the dynamic landscape of the digital age. As we continue to witness the evolution of technology, a solid grasp of Computer networks (wireless-wired) will undoubtedly be a cornerstone for success in the realm of computer science.
Protocols in Computer networks (wireless-wired)
Protocols in Computer networks (wireless-wired): A Deeper Dive
In the intricate world of Computer networks (wireless-wired), protocols serve as the unsung heroes that govern communication between devices. These standardized sets of rules and conventions ensure seamless data exchange and enable the smooth functioning of interconnected systems. Let’s delve deeper into some key protocols that play a crucial role in both wired and wireless Computer networks (wireless-wired).
Transmission Control Protocol (TCP) and Internet Protocol (IP)
TCP/IP: Often referred to together, TCP and IP form the backbone of the internet. Transmission Control Protocol (TCP) manages the assembly and disassembly of data into packets, ensuring reliable and ordered delivery. Internet Protocol (IP), on the other hand, handles the addressing and routing of these packets across the network.
Functionality: TCP/IP ensures end-to-end communication by breaking down data into packets, adding addressing information (IP), and using acknowledgment mechanisms (TCP) to confirm successful data transmission.
Hypertext Transfer Protocol (HTTP) and Hypertext Transfer Protocol Secure (HTTPS)
HTTP and HTTPS: These protocols govern the transfer of web content. HTTP is the standard protocol for transmitting data over the World Wide Web, while HTTPS (HTTP Secure) adds an extra layer of security through encryption.
Security: HTTPS encrypts data during transmission, preventing unauthorized access and securing sensitive information like login credentials and personal data.
File Transfer Protocol (FTP) and Secure File Transfer Protocol (SFTP)
FTP and SFTP: These protocols are employed for file transfer between devices. FTP is a standard network protocol used to transfer files, while SFTP adds a layer of security by employing Secure Shell (SSH) for encrypted communication.
Use Cases: FTP is commonly used for sharing files in a less secure environment, while SFTP is preferred for secure data transfer, especially in business and sensitive data exchanges.
Simple Mail Transfer Protocol (SMTP) and Post Office Protocol (POP)
SMTP and POP: Essential for email communication, SMTP is responsible for sending emails, while POP retrieves emails from a mail server.
Flow of Communication: SMTP ensures the proper delivery of outgoing emails, while POP retrieves and downloads incoming emails to the recipient’s device.
Domain Name System (DNS)
DNS: Imagine DNS as the address book of the internet. It translates human-readable domain names (like www.example.com) into IP addresses that computers use to identify each other on the network.
Resolution Process: When you enter a web address, DNS translates it into the corresponding IP address, facilitating the connection between your device and the desired website’s server.
Wireless Protocols: Wi-Fi Standards
In the realm of wireless networks, specific protocols dictate communication standards. Wi-Fi, a cornerstone of wireless connectivity, has seen several standards evolve over the years:
Evolution: These standards represent the progression of Wi-Fi technology, with each iteration introducing enhancements in terms of speed, range, and efficiency.
Compatibility: Devices supporting the latest standards can communicate seamlessly with networks conforming to earlier standards, ensuring backward compatibility.
Embracing Protocols in EMSAT Achieve Computer Science
For students preparing for the EmSAT Achieve Computer Science test, understanding protocols is integral to mastering the section on Computing Systems and Networks. Questions related to network communication layers, protocol functionalities, and the advantages of specific protocols may be part of the evaluation process.
Protocols form the invisible threads weaving the fabric of Computer networks (wireless-wired). From ensuring the secure transfer of sensitive data to facilitating seamless web browsing, these protocols are the unsung heroes of the digital age. Aspiring computer scientists and those preparing for the EmSAT Achieve Computer Science test should embrace the intricacies of protocols to navigate the complex landscape of modern network communication successfully.
Elmadrasah.com EMSAT Courses and Connection to Computer networks (wireless-wired)
As technology becomes an integral part of our daily lives, the demand for skilled professionals in computer science is soaring. Recognizing this need, Elmadrasah.com has designed comprehensive EMSAT courses, strategically tailored to prepare students for the EmSAT Achieve Computer Science test. Let’s delve deeper into how these courses establish a strong connection to the intricate world of Computer networks (wireless-wired).
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Elmadrasah.com’s EMSAT courses are meticulously crafted to align with the EmSAT Achieve Computer Science test specifications. The curriculum covers a broad spectrum of topics, ensuring that students acquire a deep understanding of Computer networks (wireless-wired), including computing systems, data analysis, impacts of computing, algorithms, and programming practices.
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The courses offered by Elmadrasah.com go beyond the basics, providing students with an in-depth exploration of computer network concepts. From hardware components like logic circuits and gates to software components encompassing network protocols, the curriculum ensures a holistic understanding of the fundamental elements that constitute Computer networks (wireless-wired).
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Elmadrasah.com recognizes the importance of practical application in mastering Computer networks (wireless-wired). The courses incorporate real-world scenarios, allowing students to apply their knowledge to solve complex problems. This hands-on approach prepares them not just for the EmSAT test but also for real-world challenges they may encounter in their future careers.
4. Emphasis on Programming Skills in Python
A distinguishing feature of the EmSAT Achieve Computer Science test is its focus on Python programming. Elmadrasah.com’s EMSAT courses equip students with robust programming skills, ensuring they are proficient in using Python to solve computational problems. This emphasis on practical coding aligns with the increasing demand for programming expertise in the field of Computer networks (wireless-wired).
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Understanding the structure and requirements of the EmSAT Achieve Computer Science test is vital for success. Elmadrasah.com‘s courses implement test-oriented preparation strategies, familiarizing students with the test format, time constraints, and question types. This targeted approach enhances their confidence and readiness on test day.
6. Personalized Learning Experience
Elmadrasah.com recognizes that each student has a unique learning style and pace. The EMSAT courses are designed to provide a personalized learning experience, catering to individual needs. Whether a student is new to computer science or seeking to deepen their understanding of specific concepts, the courses offer flexibility and adaptability.
7. Comprehensive Support for Score Improvement
The EmSAT Achieve Computer Science test provides detailed score descriptors, allowing students to gauge their proficiency levels. Elmadrasah.com’s EMSAT courses offer comprehensive support for score improvement, addressing specific areas where students may need additional assistance. This targeted approach ensures that students progress from basic knowledge to high proficiency.
8. Gateway to College-level Computer Science Courses
Successfully navigating the EmSAT Achieve Computer Science test with the help of Elmadrasah.com’s EMSAT courses opens doors to higher education. Students achieving high proficiency levels are well-prepared for college-level computer science courses, laying the foundation for successful careers in the dynamic and ever-expanding field of Computer networks (wireless-wired).
Elmadrasah.com’s EMSAT courses serve as a bridge between aspiring students and the intricate world of Computer networks (wireless-wired). By providing a specialized curriculum, in-depth coverage of concepts, practical applications, and personalized learning experiences, these courses not only prepare students for the EmSAT test but also equip them with the skills and knowledge essential for thriving in the field of computer science.
EmSAT Achieve Computer Science Test Structure
The EmSAT Achieve Computer Science test consists of two main sections: Computer Science Theory and Problem Solving and Programming Practices.
Computer Science Theory Section
This section evaluates knowledge in computing systems and networks, data analysis, and the impacts of computing. Topics such as network architecture, security, and communication layers align with the fundamental concepts of Computer networks (wireless-wired).
Problem Solving and Programming Practices Section
This section assesses problem-solving techniques and programming skills, including algorithms and programming in Python. Knowledge of programming constructs, data structures, and best practices in coding directly relates to building and maintaining efficient Computer networks (wireless-wired).
EmSAT Achieve Computer Science Score Descriptors
The EmSAT Achieve Computer Science test provides a detailed scoring system, indicating the proficiency level of test takers. Scores range from Little Knowledge of General Physics to High Proficiency, offering a comprehensive assessment of readiness for college-level courses.
In conclusion, a solid understanding of Computer networks (wireless-wired) is imperative for anyone venturing into the field of computer science. Whether preparing for the EmSAT Achieve Computer Science test or seeking to enhance general knowledge, Elmadrasah.com’s EMSAT courses provide a valuable resource. As technology continues to advance, the demand for skilled professionals in Computer networks (wireless-wired) will only increase, making it essential to grasp the basic concepts, components, and protocols discussed in this article.


Amsterdam SMS is a dynamic visualization of the volume of text messages transmitted during the run-up to and on New Year’s Eve in Amsterdam in each subsection of the city as defined by mobile communication infrastructure. The work provides a glimpse into our communication patterns around a significant event. It also indicates a certain population distribution and movement among people.
This interactive visualization tool for SMS messages was developed as part of a research project for the MIT Senseable City Lab and the Centre of Competence for Geoinformatics at Salzburg University. The visualization was built with the programming language Processing and OpenGL. Data was provided by KPN Mobile. Created in 2007, the work is an early study of a digitally integrated and connected city.
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As promised, here is a follow-up on the lab hardware selection, I’ve decided to loosely follow the INE lab specification and acquired the following Cisco hardware:
- R1 2911-K9/SEC
- R2 2911-K9/SEC
- SW1 3750X-48P-S
- SW2 3560X-24T-S
- 2x ASAx 5515X
- LWAP 3602
- IP Phone A 7965G
- IP Phone B 7965G
In addition to physical Cisco hardware, the following virtual Windows machines and Cisco security appliances are part of the SCv5 Rack,
- (2) Cisco ACS (Access Control Server)
- (2) Cisco ASAv (Adaptive Security Appliances virtualized)
- (10) Cisco CSR (Cloud Services Router)
- (2) Cisco ISE (Identity Services Engine)
- (2) Cisco ESA (Email Security Appliance)
- (2) Cisco FMCv (Firepower Management Center virtualized)
- (2) Cisco FTDv (Firepower Threat Defense virtualized)
- (2) Cisco NGIPSv (Next Generation Intrusion Prevention System virtualized – aka Cisco Firepower)
- (2) Cisco WSA (Web Security Appliance)
- Test PC A (Windows 10 x64)
- Test Server A (Windows 2012 Server)
- Test PC B (Windows 10 x64)
- Test Server B (Windows 2012 Server)
- WiFi Test PC (Windows 10 x64)
To host all of the virtual machines needed for the lab I used a Dell Poweredge R720 Server with 2x E5-2650L v2 (10 Core/20 Threads) CPUs, 144GB RAM and 2TB NVMe for local storage.
For power management I went with a APC Switched PDU as this will allow me to remotely turn the lab on and off.
For console/terminal access I used an old Raritan KSX2-188.
Here is a quick rack layout of the equipment, actual picture to follow.
The lab is wired as per INE’s Wiring Diagram for simplicity, this may or may not change when I find more time to fiddle with the setup and decide on what training providers to follow.


Ackcio Mesh – A Reliable LPWAN Standard for Industrial Monitoring
Our world today has become increasingly connected, with every industry relying heavily on automation and digital transformation to survive and thrive. Connectivity plays a crucial role in this.
When it comes to IoT connectivity, there are quite a few technologies that we come across online. Words like LoRaWAN, Sigfox, and NB-IoT are familiar to most of us. In fact, we often use one or more of these technologies in our business for data collection, remote monitoring, or people tracking use-cases. Despite the differences in their underlying technologies, they all have one thing in common—a simple single-hop long-range communication capability from an end device to a centrally placed gateway. Using more technical jargon, we call them Star LPWANs (low power wide-area network).
There is a much more capable and feature-packed alternative—Ackcio Mesh, an interesting networking technology that allows for reliable, real-time, wireless monitoring especially catered for industrial applications.
LPWAN is a general term used to describe a radio technology, proprietary or nonproprietary, that provides long-range communication (up to 1km in urban environments and up to 5km in line-of-sight environments) while operating on small batteries for several years. As such, it offers an order of magnitude improvement in range compared to the other popular radio technologies, like Bluetooth, Wi-Fi, and ZigBee.
Despite being extremely constraint in the amount of data it can transmit at any given time, this technology is gaining traction across a range of industries. Companies like Sigfox and Semtech and captured a fair share of the LPWAN market and many more service providers are fighting for a slice of the IoT Pizza.
A French global network operator, Sigfox builds LPWANs to connect low-power devices (like electricity meters and smartwatches) that require small fragments of data to be periodically pushed to the internet. In some ways, Sigfox functions similarly to a telco; but one key difference is that it operates on a license-free sub-gigahertz radio frequency bands, like 433 MHz (China), 868 MHz (Europe), 915 MHz (Australia and North America), and 923 MHz (Asia).
Being a base-level LPWAN, Sigfox’s proprietary communication technology is limited and only able to transmit a maximum of 140 messages per day to the gateway. With each payload size of up to 12-byte, applications are fairly restricted. Downlink communication is also restricted with only four messages guaranteed to be transmitted on any given day.
Geographical range is another challenge. Although Sigfox is present in up to 70 countries, its usability is limited to regions where its connectivity has been deliberately extended—typically urban areas. But even here, the star topology of the network, obstructions, and other interferences can disrupt connectivity with the gateway.
LoRaWAN is another widely-used LPWAN that operates in the same unlicensed sub-gigahertz radio frequency bands as Sigfox. On the plus side, it does not require a fixed infrastructure by an operator, provides a considerably higher payload strength (up to 250 bytes), and can transmit an unlimited number of messages. Tests have shown an enormous range of communication in near ideal situations with a direct line of sight.
NB-IoT is another promising LPWAN technology that is progressively being rolled out by many Telcos. Like Sigfox, it depends on an infrastructure maintained by network providers. While NB-IoT offers better performance in terms of reliability and higher uplink and downlink capacity, it consumes higher energy (roughly 3 to 5 times higher compared to other LPWANs like LoRa and Sigfox). This makes it less suitable for long-term battery dependent deployments.
Moreover, due to the dependence on fixed infrastructure, it is ill-suited for deployments in remote areas where the coverage is not yet established or not economically feasible for the telcos to setup. Even in urban environments, where the coverage exists, underground applications like tunnels or metro construction suffer.
Ackcio’s Mesh Network offers the same long-range communication as other LPWAN suppliers in the market but with certain key advantages. Our devices form a complex multi-hop mesh network to better route data around obstructions.
When compared with traditional 2.4 GHz mesh networks, Ackcio Mesh Network provides kilometers of range in every-hop, thus allowing for deployments in challenging environments like tunnels and large construction sites and mines.
Ackcio Mesh allows redundant paths in the network to be utilized for data transmission. This prevents data loss due to obstructions, the creation of dead zones within the network, and allows a more distributed data storage for recovery. The complex multihop mesh networking architecture eliminates a single point of failure and makes the network more reliable.
Ackcio Mesh is easily scalable. Not only adding new devices to the network is as easy as just turning them on, but also the addition of new devices to the network also creates many more pathways towards the Gateway and enhances the network coverage. This allows users to set up large network deployments without multiple gateways and allows perfect load balancing.
The widespread adoption of LPWANs, as well as a lack of licensing, have made the sub-GHz spectrum increasingly saturated. This, in turn, leads to severe interference, enough to cause a reduction in bandwidth and an increase in latency. Ackcio Mesh uses multiple frequencies to avoid such interferences. By leveraging an industry-standard Time Synchronous Channel Hopping (TSCH) protocol, Ackcio Mesh transmits data using a different pseudo-randomly selected frequency, thereby avoiding repetitive transmission failure.
Building a Mesh networking protocol is a complicated task as is its deployment and maintenance. To simplify this process, Ackcio Mesh uses RPL, an industry-standard self-healing routing protocol. As such, the deployment process can be as simple as switching on the devices, and the software running on the devices automatically finds the best route to the nearest gateway.
Ackcio Mesh offers network-wide time synchronization down to a few milliseconds, allowing sensor data from different devices within a multi-hop network to be captured simultaneously. This is particularly beneficial to applications that require correlated readings from multiple sensors.
Ackcio Mesh sensors energy-efficient time-synchronized wakeups to exchange information reliably between adjacent devices with automatic time drift corrections and compensation to reduce the radio on time. The devices only wake up when they are supposed to and for a very small amount of time. As a result, they only draw close to 20µA current for over 99% of the time, making the devices last for years on batteries.
Based on IEEE 802.15.4g and IPv6 industry standards, Ackcio Mesh offers multi-hop bidirectional links that allow users to reconfigure devices remotely and collect data on demand. The latter allows users to immediately verify whether an outlier reading is true or a false positive instead of waiting for the next scheduled data transmission.
Being a high-level LPWAN, Ackcio Mesh forms a primary component of Ackcio Beam, our state-of-the-art wireless monitoring system for geotechnical and structural sensors.
Thanks to its unique combination of advanced features, Ackcio Mesh facilitates the wireless transmission of data from remote sensors to our client’s fingertips in real-time, buying them valuable time and intelligence to make timely data-driven decisions. As such, Ackcio Mesh helps distinguish Ackcio Beam as the new industry standard for wireless monitoring applications.
Visit our main page to find out more about how we can advance the safety and stability of your infrastructure.


French Telecommunication firm Orange has partnered with Mozilla to launch Orange Klif in thirteen Orange markets in Africa, these include; Kenya Egypt, Senegal, Tunisia, Cameroon, Botswana, Madagascar, Mali, The Ivory Coast, Jordan, Niger, Mauritius and Vanuatu.
“Through these launches, Mozilla and Orange deliver on the promise of putting the mobile web within reach of millions more people not previously addressed by mobile offers,” Mozilla said in a blog post. Firefox OS smartphones aren’t meant to stand up against iPhones or flagship Android devices. Mozilla is trying to get devices in the hands of people who’ve never owned any type of smartphone — a potential market that is by all accounts massive and could bring significant growth. The Africa launch shows that Mozilla is serious about reaching that goal.
In Kenya, Orange Telkom seeks to leverage on the affordability of the device to capture the low income data users with the firefox operating system smartphone priced at KSh4000.
The smartphone with dual SIM and 3G is the company’s latest stab at the fast growing data market dominated by Safaricom.
“The Orange Klif’s launch is part of our strategy of ensuring our network expansion into the country is supported by the provision of quality, devices for our entry level customers,” said Orange Telkom Kenya CEO, Vincent Lobry.
Internet users in the country stood at 26 million at the end of last year with Orange Telkom having 2.2 million of these, government data shows.
“Customers seeking to upgrade from 2G feature phones to 3G smartphones can enjoy the benefits of multimedia and online usage without experiencing bill shocks,” says Lobry.
The battle to control the data market has seen the mobile phone service providers move to drive device sales as voice revenues plateau.
Firefox OS is the first truly open mobile platform built entirely on Web technologies, bringing more choice and control to the mobile industry.


zenon is an open-design, object-oriented industrial automation application. The zenon Product Family is used by many companies around the world for process visualization, as a Human-Machine-Interface (HMI) and as a Supervisory Control and Data Acquisition (SCADA) system. Its openness makes fast, efficient interfaces with any hardware or software possible.
The HMI/SCADA system zenon communicates via standard interfaces such as COM, ActiveX, XML or zenon's own process gateway. It can also communicate with many proprietary interfaces, including, for instance, RFC/BAPI as used by SAP®. All the control connections are programmed in-house at COPA-DATA, fine-tuned for the target system and then exhaustively tested.


Monster iCarPlay Wireless Radio iPod SystemIn essence with the Monster iCarPlay setup you get a cable that plugs into your car's cigarette lighter. The other end plugs into your iPod. In between these two ends is a radio station chooser. You can rotate between three different channels. You choose one of the channels, and tune your car's radio station to that channel. Voila! The signal sends out wirelessly from your iPod right into the radio system.
Because there are 3 stations to choose from, you should be able to fine 1 of them that is not currently occupied by a strong local signal. Usually on my radio at least 2 if not all 3 are able to be used. There's no clicking noise from tape player connections, no other issues. The signal is clear and strong.
We've even used this on drives where one person was following the other and both people could listen to the story or the book-on-tape. That's a pretty cool feature :)
The only real downside is the cost. When I purchased this, it was about a $100 unit. That's as much as some MP3 systems! Nowadays the price has come down a lot so that's less of an issue.
Also the connector that goes into the iPod isn't a regular headphone jack connection - it goes into the data transmission end. So the system only works with an iPod (or other MP3 players that use the exact same jack as the iPod does).
That being said, if you want nice, clear iPod sound in your car, and can spare the money, this is the way to go. We've used ours for years and are very pleased with it.
We purchased our unit with our own funds.
Buy the Monster iCarPlay Wireless Radio iPod System from Amazon.com
MP3 Hardware Reviews
Music / MP3 Tips and Information


Lifeline Communicator Units
Two different Lifeline Communicators are available:
A Regular Lifeline Communicator that is connected to an active telephone jack and electrical outlet. This type of unit allows you to connect your existing phone into back of the Lifeline unit so that your phone works through the Lifeline unit.
A Wireless Lifeline Communicator that works with it's own cellular technology; this unit is connected to an electrical outlet in your home.
All Lifeline Communicator Units have a back up battery and work during power outages.


XP, 2003, 2008, 2012, 2016, 2019, 2022, Vista, Windows 7, Windows 8, Windows 10, Windows 11
Supported Protocols:NTP, SNTP, NTSv2
Supported Networks:Intranet, LAN, WAN, Internet
Network Time Client is part of the Network Time System package responsible for synchronizing time on Windows based workstations where it is installed. The application is capable of automatically searching for time server(s) on the corporate network of any complexity, from LANs to multiple routing networks. Setting a time server manually is also possible.Quick Tour
NTP Client Key features:
Multi-protocol supportNetwork Time System (NTP Client) supports both our own advanced time protocol (NTSv2) and the most widely used NTP and SNTP time sync protocols.
Two ways of locating network time serversThe application can find time servers running Network Time System (Server) by either sending out UDP broadcast requests or resolving the "timeserver.nts" host and connecting directly to the resolved IP address. The latter gives you the opportunity of setting up a stable time system by combining a series of physical and virtual time servers installed on different machines and/or locations of the company network.
Custom server listNetwork Time System (Client) is able to simultaneously gather time from several NTSv2 or NTP Servers and choose the fastest one to adopt the time from.
Accepting time via UDP broadcastingThe NTSv2 time protocol allows Network Time System (Server) to transmit the source time to the clients by sending NTSv2-UDP broadcasts that Network Time System (Client) can accept.
Time synchronization schedulingA built-in scheduler helps you easily set up time synchronization intervals.
Working on logged on and logged off machinesNetwork Time Client is a system service application that starts working right after Windows is loaded, whether there are any users logged on or not.


Since its inception in 1958, NASA has relied exclusively on radio frequency (RF)-based communications as the only viable medium for exchanging data between a mission and a spacecraft. Today, with missions demanding communication with higher data rates than ever before, NASA is taking steps to embark on a new era of communication technology.
The Laser Communication Relay Demonstration (LCRD) project will help pave the way, pioneering technologies that will enable the exchange of data through beams of light.
Space laser communications technology has the potential to provide 10 to 100 times higher data rates than traditional radio frequency systems for the same mass and power. Alternatively, numerous studies have shown that a laser communications system will use less mass and power than a radio frequency system for the same data rate.
Video credit: NASA Goddard
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