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. analyze
B. parse
C. delete
D. create
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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. 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. but rather
B. rather too
C. rather than
D. rather that
For each blank, choose the best answer from the four choices and write down on the answer sheet. (21) is a six bytes OSI layer 2 address which is burned into every networking device that provides its unique identity for point to point communication. (22) is a professional organization of individuals in multiple professions which focuses on effort on lower-layer protocols. (23) functions with two layers of protocols. It can connect networks of different speeds and can be adapted to an environment as it expands. (24) is the popular LAN developed under the direction of the IEEE802.5. (25) is the popular backbone technology for transmitting information at high speed with a high level of fault tolerance which is developed under the direction of ANSI.
A. X.25
B. ATM
C. FDDI
D. SMDS
Packet-switching wireless networks are preferable (41) when transmissions are (42) because of the way charges are (43) per packet. Circuit-switched networks are preferable for transferring large files or for other lengthy transmissions because customers are (44) for the (45) of time they use the net-work.
A. charged
B. fined
C. free
D. controlled