Quiz 9: Computer Networks


Videoconferencing Cisco Systems: Cisco Systems is the world's leading supplier of the equipments of videoconferencing, systems and different services and the networking computer products. The software used enables the point-to-point and the multipoint video conferences and with such software's live conferences at various sites can be possible by using the computer networks. Tandberg: The Tandberg video-conferencing system delivers the product with high-performance lines for conducting all the needs of video communication. It delivers unparalleled quality, ease-of use and reliability. The software offerings includes conference scheduling software's, IPVCi's IntelliNet is basically used to provide various services of video-conferencing. Radvision: Radvision is a leading and highest provider of the video-conferencing and the telepresence technologies over the wireless networks and the IP. The radvision and its co- partner Avaya are enhancing the unified communications that helps in the forward evolution with the various unique technologies that will harness the video powers along with the powers of data and voice over any of the network. The software offerings includes products that provide various benefits that include software products regarding telepresence, video management, video conference systems, video infrastructure, video and voice monitoring solutions, and various software quality developer products. Polycom: Polycom had introduced the high definition video conferencing system that delivers and provides the customers a very cost-effective path of migration so as to provide leverage to the existing video communications of investment. The software offerings includes products that helps in providing HD Telepresence and the video conferencing, various software and hardware products for Microsoft, and various voice products. In each company's product line, the related standards supported by each includes: Cisco System have Unique Device Identifier or UDI as the product Identification standard for the hardware products. Tandberg consist of ITU H.323 standard for communications especially for the projects of VoIP that includes its services with the Telenor. Radvision consists of solutions that are basically based on the standards and supports the H.323 and SIP along with standards including ISDN and 3G wireless. Radvision also initiated the activities for VoIP based communication systems. Polycom consists of native, simultaneous H.323, and SIP standards supported by it. It also consists of standards based on the room systems and the MCUs that seamlessly connect. Cisco Systems and Tandberg supports high-definition video, and the related standards includes SCOPIA product of radvision, which is basically a powerful combination of software and hardware products. The available infrastructure products that includes multipoint control units MCUs, gatekeepers includes radvision products that includes scopia management that delivers management and schedules and controls for the robust and easy to use conferencing. The use of such infrastructures is much faster than the switches and routers so their capability is much faster than them.

TCP/IP Model The TCP/IP layered model consists of five layers and each layer serves differently for the network hardware and software. The functions of each layer of the TCP/IP Model are given as follows: 1. Application Layer: This layer mainly supports the application and the end-user processes. Various communicating partners are thus identified and the quality of the service is also identified, thus the authenticity of the user and the privacy of the user are considered and the constraints on the data syntax are thus identified. 2. Transport Layer: The transport layer provides the transfer of the data and the messages between the end systems or the hosts, and is thus also responsible for the end-to-end recovery of error and the flow of control. This layer consists of TCP and UDP protocols. 3. Internet Layer: This layer basically corresponds to the layer of OSI model that is network layer. It is basically the primary protocol and is a very supporting protocol. 4. Network Layer: The network layer provides the various routing and the switching technologies that create the logical paths called as the virtual circuits for transmitting the data from one node to another node. Thus, the main function of this layer is basically to connect the internet protocol to the underlying network protocols within the physical layer. 5. Physical Layer: This layer basically contains the various physical network protocols. The main function of this layer is basically to convey the electric impulse and bit stream, various light or the radio signals via the network at the various electrical and mechanical levels.

Physical Network Standards The IEEE 802 standards define many aspects of physical networks. Explanation: The IEEE includes several network standards under it these are collectively called as the IEEE 802 standards. These standards describe the physical network hardware's, various transmission methods, media, and the protocols.