Both bus and tree topologies are characterized by the use of multipoint (1). For the bus, all stations attach, through appropriate hardware (2)known as a tap, directly to alinear transmission medium, or bus. Full-duplex operation between the station and the tap allowsdata to be transmitted onto the bus and received from the (3). A transmission from anystation propagates the length of the medium in both directions and can be received by all other(4). At each end of the bus is a (5), which absorbs any signal, removing it from thebus. (4)是()
A. routers
B. stations
C. servers
D. switches
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One of the main responsibilities of ICMP is to report (1). Although technology has produced increasingly reliable transmission media, errors still exist and must be handled. IP is an (2)protocol. This means that error checking and error control are not a concem ofIP JCMP wasdesigned, in part, to compensate for this shortcoming. Howerver, ICMP does not (3)errors, itsimply reports them. Error correction is left to the higher-level protocols. Error messages arealways sent to the original(4) because the only information available in the datagram aboutthe route is the source and destination 1P addresses. ICMP uses the source IP address to send theerror massage to the source of the (5) (3)是()
A. correct
B. conduct
C. produce
D. Connect
We have already covered the topic of network addresses. The first (1) in a block (in class A, B, and C) defines the network address. In classes A, B, and C, if the hosted is all 1 s, the addressis called a direct broadcast address. It is used by a (2)to send a packet to all hosts in a specificnetwork. All hosts will accept a packet having this type of destination address. Note that thisaddress can be used only as a (3) address in an IP packet. Note also that this special addressalso reduces the number if available hosted for each netid in classes A, B, and C.In classes A, B, and C, an address with all 1 s for the netid and hosted (32 bits) define a (4) address in the current network. A host that wants to send a message to every other hosts can use this address as destinationaddress in an IP packet. However, a router will block a packet having this type of address to confine thebroadcasting to the (5) network. Note that this address belongs to class E. (4)是()
A. unicast
B. multicast
C. broadcast
D. anycast
A transport layer protocol has several responsibilities, One is to create a process-to-process (program-to-program) communication; TCP uses port (1) to accomplish this. Anotherresponsibility of a transport layer protocol is to create a(2)and error-control mechanism atthe transport level. TCP uses a sliding(3)protocol to achieve flow control. It uses theacknowledgment packet, time-out, and retransmission to achieve (4) control. The transportlayer is also responsible for providing a connection mechanism for the application program. Theapplication program sends (5)of data to the transport layer. It is the responsibility of thetransport layer at the sending station to make a connection with the receiver. (5)是()
A. ports
B. streams
C. packets
D. cells
One of the main responsibilities of ICMP is to report ______. Although technology has produced increasingly reliable transmission media, errors still exist and must be handled. IP is an ______ protocol. This means that error checking and error control are not a concem ofIP JCMP wasdesigned, in part, to compensate for this shortcoming. Howerver, ICMP does not ______ errors, itsimply reports them. Error correction is left to the higher-level protocols. Error messages arealways sent to the original ______ because the only information available in the datagram aboutthe route is the source and destination 1P addresses. ICMP uses the source IP address to send theerror massage to the source of the ______.
A. datagram
B. frame
C. service
D. Protocol