52.The network layer provides services to the transport layer.It can be based on either( ). In both cases, its main job is ( )packets from the source to the destination.
In network layer, subnets can easily become congested, increasing the delay and ( )for packets.Network designers attempt to avoid congestion by proper design.Techniques include ( ) policy, caching, flow control, and more.
The next step beyond just dealing with congestion is to actually try to achieve a promisedquality of service.The methods that can be used for this include buffering at the client, trafficshaping, resource ( ), and admission control.Approaches that have been designed forgood quality of service include integrated services (including RSVP), differentiated services, and MPLS.
问题1选项
A.virtual circuits or datagrams
B.TCP or UDP
C.TCP or IP
D.IP or ARP
问题2选项
A.dealing with
B.routing
C.sending
D.receiving
问题3选项
A.lowering the throughput
B.lowering the correctness
C.lowering the effectiveness
D.lowering the preciseness
问题4选项
A.abandonment
B.retransmission
C.checksum
D.synchronism
问题5选项
A.distribution
B.guarantee
C.scheme
D.reservation