For each blank, choose the best answer from the four choices and write down on the answer sheet. (11) is a protocol that a host uses to inform a router when it joins Or leaves an Internet multicast group. (12) is an error detection code that most data communication networks use. (13) is an interior gateway protocol that uses a distance vector algorithm to propagate routing information. (14) is a transfer mode in which all types of information are organized into fixed form cells on an asynchronous or non-periodic basis over a range of media. (15) is an identifier of a web page.
A. ISDN
B. X.25
C. Frame Relay
D. ATM
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In the following essay, each blank has four choices. Choose the most suitable one from the four choices and write down in the answer sheet. A socket is basically an end point of a communication link between two applications. Sockets that extend over a network connect two or more applications running on (31) computers attached to the net-work. A socket (32) two addresses: (33) . Sockets provide a (34) communication channel between one or more systems. There are (35) sockets separately using TCP and UDP.
A. unique
B. separate
C. same
D. dependent
Networks can be interconnected by different devices in the physical layer networks can be connected by (1) or hubs. Which just move the bits from one network to an identical network. One layer up we find bridges and switches which operate at data link layer. They can accept (2) examine the MAC address and forward the frames to a different network while doing minor protocol translation in the process in me network layer, we have routers that can connect two networks, If two networks have (3) network layer, the router may be able to translate between the packer formats. In the transport layer we find transport gateway, which can interface between two transport connections Finally, in the application layer, application gateways translate message (4) . As an example, gateways between Internet e-mail and X.400 e-mail must (5) the e-mail message and change various header fields.
A. syntax
B. semantics
C. language
D. format
In the following essay, each blank has four choices. Choose the most suitable one from the four choices and write down in the answer sheet. Open Shortest Path First (OSPF) is a (36) routing algorithm that (37) work clone on the OSI IS-IS intradomain routing protocol. This routing, as compared to distance-vector routing, requires (38) processing power. The (39) algorithm is used to calculate routes. OSPF routing table updates only take place when necessary, (40) at regular intervals.
A. Bellman-Ford
B. Ford-Fulkerson
C. Dijkstra
D. RIP
Frame Relay is simplified form of (51) , similar in principle to (52) , in which synchronous, frames of data are routed to different destinations depending on header information. Packets are routed throught one or more Virtual Circuits known as (53) . Most Virtual Circuits are (54) , which means that the network provider sets up all DLCI connections at subscription time. (55) are also part of the Frame Relay specification. They privide a link that only lasts only as long as the session.
A. X.21
B. X.25
C. X.28
D. X.29