The Various Devices Of Communication Systems Information Technology Essay
Communication devices route and transmit information to various devices, including radio and telephone systems. Communications devices transmit voice and audio signals to telephone and cellular phones, which receive and reconvert the waves back into sound. Transmissions may be wired or wireless, depending on the application. Most telephones are wired, whereas cellular phones use wireless technology. Telephones themselves are communication devices and include a number of components and accessories including adapters, batteries, and electrical elements. Other communication devices commonly used for audio and telephone applications include magnetic receivers, optical interconnects, and switchboards. Magnetic receivers are communication devices that detect the magnetic fields emitted by a transmitter. Optical interconnects transmit information through optical cables, which are capable of higher bandwidth compared to traditional cables. Phone switchboards route communications and add advanced features to telephone systems.
Telephone systems may also employ automated voice answering systems to take messages and provide automated information retrieval requests. These communication devices are commonly used in call centres and for technical support applications. Communication devices also transmit information to radios and pagers. Radios are communication systems that send and/or receive electromagnetic waves and consist of a transmitter, receiver, and antenna. Pagers are electronic communications devices that are used to notify or alert a user. Communication received by pagers may be numeric or alphanumeric, depending on the model and complexity of the device. Other types of communication devices include navigation systems, such as global positioning systems (GPS) instruments and radar systems. GPS communication devices receive satellite communications and use it to provide position information. Radar communication devices use synchronized transmitters and receivers to send radio waves and detect their reflections from objects, surfaces and sub-surface structures.
List of Communication Devices
Automated Answering Devices
Hubs and Bridges
Routers and Switches
Other Networking devices
There are different communication devices such as routers, hub, switches and brides. These devices are required to transmit the data between one computer and another. Based on the infrastructure of your network, you need to use different devices. Hub and Switch are the LAN devices and the router is a LAN/WAN device. These devices provide the medium of sending and receiving the data and connect the LAN and WAN segments of a network. The other network devices are gateways, CSU/DSU, wireless access points, modems, ISDN adapters, proxy, firewall, multiplexer, digital media receiver, load balancers and the NIC adapter. Each of these devices plays a specific role in a computer network and only the complex and the large network use all these devices. Being a network engineer or the systems administrator, you need to know the role and features of each device in your network.
Hub is a LAN networking device and every computer in an Ethernet based network is directly connected with the hub. All the computers that are connected to the network share the same bandwidth. When a hub receives the data packets at one of its port, it distributes the data signals to all the ports in a network. When two or more computers try to send the data signals at the same time, a collision occurs and the process is known as Carrier Sense Multiple Access / Collision Detection. Hubs are usually come with the 4, 8, 16 and 24 ports. In the data communications, a hub is a place for the convergence where data arrives from multiple directions and forward to the multiple directions. The most advanced form of the hub is the intelligent or smart hub that contains the management software which is used to troubleshoot the most common problems.
Bridges are the networking devices that divided up the network into different segments to reduce the amount of traffic on each network. A bridge blocks and forwards the data packets based on their MAC addressees. Be blocking the unnecessary traffic to enter the other part of the network segments, it reduces the amount of traffic and the other issues such network congestions and the bottleneck. There are following three common types of the bridges.
A Transparent bride is invisible to the other part of the computer network and it performs the functions of blocking and forwarding the data packets based on the MAC addressees. They are the most popular types of the bridges.
Translation bridges are used to connect the two different networks such as Ethernet and Token Ring. It translates the data and forward to the other network.
Source-Route bridges are designed for the Token Ring networks. In the Source-Route Bridge, the entire route of the network frame is embedded into the frame.
A network switch is a LAN/WAN communication device. It joins the multiple computers together in the LAN and WAN. In the LAN, the switches do not broadcast the data to all the connected computers like the hub. Based on the IP/MAC addresses of the computer, a switch sends data only to the destined computer. Switches operate on the data link and network layers of the OSI layers model. Different models of the switches support the different number of the connected devices. In the LAN, switches support 10mbps 10/100 mbps or 100mbps data transmission speed. A switch conserves the bandwidth and offers the grater performance than the hub.
A router is a networking device that is used to connect the two or more logically and physically different networks. On the internet, the routers plays the functions of sorting and distribution of the data packets based on the IP addresses of the destination router or computer. Router use the header and forwarding table to choose the best shortest path to transmit the data towards the destination. A router is used to connect the two LANs, two WANs, and LAN with WAN and a LAN with the ISP network. Router uses the ISDN, frame relay, ATM and other communication technologies. A router operates at the network layer of the OSI model.
Global positioning system (GPS) instruments and GPS modules are radio-navigational devices that provide accurate position information about objects on Earth, based on information from orbiting satellites. Equipped with rubidium atomic clocks, 24 GPS satellites in high-orbital planes use coarse acquisition (C/A) codes to communicate with GPS ground stations. These Earth-based control segments monitor almanac and ephemeris signals from GPS satellites, and communicate the small corrections that become necessary when there are changes to either a satellite’s orbit or to Earth’s ionosphere. By using the information in the almanac and ephemeris signals, GPS receivers can determine the time required to transmit a signal. Because that time is proportional to the distance traveled, GPS modules and devices can determine the arc on which the GPS receiver lies and, therefore, the intersection point and position. Selecting GPS instruments and GPS modules requires an analysis of parameters for product type, performance, power, and connection and communication. Product types include GPS receivers, GPS transmitters, GPS antennas, and GPS data loggers. Performance specifications for GPS receiver modules include the number of channels, frequency range, sensitivity, position accuracy, and time to first fix.