COMPUTER NETWORKS

•  What are the two types of transmission technology available?

            (i) Broadcast   and      (ii) point-to-point

•    What is subnet?

            A generic term for section of a large networks usually separated by a bridge or router.

•   Difference between the communication and transmission.

            Transmission is a physical movement of information and concern issues like bit polarity, synchronisation, clock etc.

            Communication means the meaning full exchange of information between two communication media.

•  What are the possible ways of data exchange?

            (i) Simplex       (ii) Half-duplex           (iii) Full-duplex.

•   What is SAP?

            Series of interface points that allow other computers to communicate with the other layers of network protocol stack.

•    What do you meant by "triple X" in Networks?   

The function of PAD (Packet Assembler Disassembler) is described in a document known as X.3. The standard protocol has been defined between the terminal and the PAD, called X.28; another standard protocol exists between hte PAD and the network, called X.29. Together, these three recommendations are often called "triple X"

•    What is frame relay, in which layer it comes?

Frame relay is a packet switching technology. It will operate in the data link layer.

           

•   What is terminal emulation, in which layer it comes?

            Telnet is also called as terminal emulation. It belongs to application layer.

•    What is Beaconing?

            The process that allows a network to self-repair networks problems. The stations on the network notify the other stations on the ring when they are not receiving the transmissions. Beaconing is used in Token ring and FDDI networks.

•    What is redirector?

            Redirector is software that intercepts file or prints I/O requests and translates them into network requests. This comes under presentation layer.

•    What is NETBIOS and NETBEUI?

            NETBIOS is a programming interface that allows I/O requests to be sent to and received from a remote computer and it hides the networking hardware from applications.

            NETBEUI is NetBIOS extended user interface. A transport protocol designed by microsoft and IBM for the use on small subnets.

•    What is RAID?

            A method for providing fault tolerance by using multiple hard disk drives.

•    What is passive topology?

            When the computers on the network simply listen and receive the signal, they are referred to as passive because they don’t amplify the signal in any way. Example for passive topology - linear bus.

•     What is Brouter?

            Hybrid devices that combine the features of both bridges and routers.

•    What is cladding?

            A layer of a glass surrounding the center fiber of glass inside a fiber-optic cable.

•   What is point-to-point protocol

            A communications protocol used to connect computers to remote networking services including Internet service providers.

•     How Gateway is different from Routers?

            A gateway operates at the upper levels of the OSI model and translates information between two completely different network architectures or data formats

•     What is attenuation?

            The degeneration of a signal over distance on a network cable is called attenuation.

•    What is MAC address?

            The address for a device as it is identified at the Media Access Control (MAC) layer in the network architecture. MAC address is usually stored in ROM on the network adapter card and is unique.

              Difference between bit rate and baud rate.

            Bit rate is the number of bits transmitted during one second whereas baud rate refers to the number of signal units per second that are required to represent those bits.

baud rate  = bit rate / N

where N is no-of-bits represented by each signal shift.