Found 1625 Articles for Computer Network

The alternative to parallel transmission, called serial transmission, sends one bit at a time. With the importance of speed, it may seem that anyone designing a data communications system would choose parallel transmission. However, most communication systems use serial mode.Following are the two main reasons for serial transmission−First, serial networks can be continued over long distances at much less cost because fewer physical wires are required, and intermediate electronic elements are less cheap.Second, using only one physical wire defines that there are never timing issues caused by one wire being slightly higher than another (a difference of millimetres can be ... Read More

To establish a reliable service between two machines on a network, transport protocols are implemented, which somehow resembles the data link protocols implemented at layer 2. The major difference lies in the fact that the data link layer uses a physical channel between two routers while the transport layer uses a subnet.Following are the issues for implementing transport protocols−Types of ServiceThe transport layer also determines the type of service provided to the users from the session layer. An error-free point-to-point communication to deliver messages in the order in which they were transmitted is one of the key functions of the ... Read More

HTTP represents "Hypertext Transfer Protocol." HTTP is the protocol that can transfer information over the network. It is the Internet protocol suite method and defines commands and functions used for sharing web page data.HTTP uses a server-client model. A client, for example, maybe a laptop or telephone device. The HTTP server is frequently a web host running web server software, such as Apache or IIS.HTTP also represents commands such as GET and POST, which are used to handle submissions on websites. The CONNECT command can act as a fast connection that is encrypted using a secure socket layer (SSL).HTTP is ... Read More

FDDI stands for Fiber Distributed Data Interface. It is a collection of ANSI and ISO standards for data transmission on fiber-optic lines in a local area network (LAN) that can broaden in the range up to 200 km (124 miles). The FDDI protocol depends on the token ring protocol.FDDI cabling consists of two fiber rings, one transmitting clockwise and the other transmitting counterclockwise. Fiber Distributed Data Interface (FDDI) is generally implemented as a dual token-passing ring within a ring topology (for campus networks) or star topology (inside a building). The dual ring includes a primary and secondary ring.The primary ring ... Read More

IMAP stands for Internet Message Access Protocol. It is a standard protocol for creating email on a small server from a local user. It is an application-layer Internet Protocol utilizing the basic transport layer protocols to create host-to-host communication services for applications. This enables the use of a remote mail server. The well-known port location for IMAP is 143.The IMAP architecture allows users to send and receive emails through a small server without support from a specific device. This type of email access is the goal for travelers receiving or answering emails from their home desktop or office system.This method ... Read More

The error-reporting message defines that the router encounters a problem when it processes an IP packet, then it reports a message. Error messages are continually transmitted to the original source because the only data possible in the datagram around the route is the source and destination IP addresses.The error reporting messages are generally classified into the following types−When a router cannot route a datagram, or a host cannot transfer a datagram, the datagram is rejected, and the router or the host share a destination-unreachable message back to the source host that proposed the datagram.Destination unreachable messages with codes 2 or ... Read More

The parallel transmission defines a transmission structure that shares multiple data bits at a similar time over separate media. In general, parallel transmission can be used with a wired channel that uses multiple, separate wires.The figure given below shows the concept and shows why engineers use the term parallel to characterize the wiring.The figure omits two important elements. First, in addition to the parallel wires that each hold data, a parallel interface generally includes other wires that enable the sender and receiver to coordinate. Second, to create installation and troubleshooting simply, the wires for a parallel transmission system are located ... Read More

Frequency Division Multiplexing (FDM) is a technology that transmits multiple signals simultaneously over a single transmission path, such as cable or wireless system. Each carrier is modulated by the data such as text, voice, video etc. Orthogonal FDM spread spectrum technique distributes the data over a large number of carriers that are spaced apart at precise frequencies. This spacing provides the “orthogonality.” This technique, which avoids the demodulators from seeing frequencies other than their own.The basic approach of OFDM is shown in the figure below −The benefit of OFDM is high spectral efficiency, resiliency due to RF interference and lower ... Read More

Bluetooth is a proprietary open wireless technology measure for exchanging information over short areas (using short-wavelength radio channels in the ISM band from 2400-2480 MHz) from permanent and mobile devices.It can be creating personal area networks (PANs) with high levels of security. It was made by telecoms vendor Ericsson in 1994, and it was initially conceived as a wireless method to RS-232 data cables. It can connect multiple devices, overcoming issues of synchronization.Bluetooth is handled by the Bluetooth Special Interest Group, which has more than 14, 000 member companies in telecommunication, computing, networking, and used electronics. Bluetooth is a free ... Read More

TCP represents Transmission Control Protocol. It is a transport layer protocol that facilitates the transmission of packets from source to destination. It is a connectionoriented protocol that defines it creates the connection before the communication that appears between the computing devices in a network.TCP organizes information so that it can be sent between a server and a user. It maintains the integrity of the information being communicated over a network. Before it sends data, TCP creates a connection between a source and its destination, which it provides remains live until communication starts. It then divides huge amounts of information into ... Read More