COMPUTER NETWORKS

KEY TERMS in Computer Networks

Following are some important terms, which are frequently used in context of Computer Networks.

TermsDefinition
1. ISOThe OSI model is a product of the Open Systems Interconnection project at the International Organization for Standardization. ISO is a voluntary organization.
2. OSI ModelOpen System Interconnection is a model consisting of seven logical layers.
3. TCP/IP ModelTransmission Control Protocol and Internet Protocol Model is based on four layer model which is based on Protocols.
4. UTPUnshielded Twisted Pair cable is a Wired/Guided media which consists of two conductors usually copper, each with its own colour plastic insulator
5. STPShielded Twisted Pair cable is a Wired/Guided media has a metal foil or braided-mesh covering which encases each pair of insulated conductors. Shielding also eliminates crosstalk
6. PPPPoint-to-Point connection is a protocol which is used as a communication link between two devices.
7. LANLocal Area Network is designed for small areas such as an office, group of building or a factory.
8. WANWide Area Network is used for the network that covers large distance such as cover states of a country
9. MANMetropolitan Area Network uses the similar technology as LAN. It is designed to extend over the entire city.
10. CrosstalkUndesired effect of one circuit on another circuit. It can occur when one line picks up some signals travelling down another line. Example: telephone conversation when one can hear background conversations. It can be eliminated by shielding each pair of twisted pair cable.
11. PSTNPublic Switched Telephone Network consists of telephone lines, cellular networks, satellites for communication, fiber optic cables etc. It is the combination of world's (national, local and regional) circuit switched telephone network.
12. File Transfer, Access and Management (FTAM)Standard mechanism to access files and manages it. Users can access files in a remote computer and manage it.
13. Analog TransmissionThe signal is continuously variable in amplitude and frequency. Power requirement is high when compared with Digital Transmission.
14. Digital TransmissionIt is a sequence of voltage pulses. It is basically a series of discrete pulses. Security is better than Analog Transmission.
15. Asymmetric digital subscriber line(ADSL)A data communications technology that enables faster data transmission over copper telephone lines than a conventional voice band modem can provide.
16. Access PointAlternatively referred to as a base station and wireless router, an access point is a wireless receiver which enables a user to connect wirelessly to a network or the Internet. This term can refer to both Wi-Fi and Bluetooth devices.
17. Acknowledgement (ACK)Short for acknowledgement, ACK is an answer given by another computer or network device indicating to another computer that it acknowledged the SYN/ACK or other request sent to it.
Note: If the signal is not properly received an NAK is sent.
18. Active TopologyThe term active topology describes a network topology in which the signal is amplified at each step as it passes from one computer to the next.
19. AlohaProtocol for satellite and terrestrial radio transmissions. In pure Aloha, a user can communicate at any time, but risks collisions with other users' messages. Slotted Aloha reduces the chance of collisions by dividing the channel into time slots and requiring that the user send only at the beginning of a time slot.
20. Address Resolution Protocol(ARP)ARP is a used with the IP for mapping a 32-bit Internet Protocol address to a MAC address that is recognized in the local network specified in RFC 826.