For (1) service, we need a virtual-circuit subnet. Let us see how that works. The idea behind virtual circuits is to avoid having to choose a new (2) for every packet sent. Instead,when a connection is established, a route from the(3) machine to the destination machine is chosen as part of the connection setup and stored in tables inside the (4) . That route is used for all traffic flowing over the connection, exactly the same way that the telephone system works.When the connection is released, the virtual circuit is also terminated. With connection-oriented service, each packet carries an (5) telling which virtual circuit it belongs to.

A:source B:route C:destination D:host

下面哪个是正确的默认路由（default route）？（）。

A:route ip 172.0.0.0 255.0.0.0s0 B:ip route 0.0.0.00.0.0.0 172.16.20.1 C:ip route 0.0.0.0255.255.255.255 172.16.20.1 D:route ip 0.0.0.0255.255.255.0 172.16.10.1150

Border Gateway Protocol(BGP) is inter-autonomous system (96) protocol. BGP is based on a routing method called path vector routing. Distance vector routing is not a good candidate for inter-autonomous system routing because there are occasions on which the route with the smallest (97) count is not the preferred route. For example, we may not want a packet through an not secure even though it is the shortest route. Also, distance vector routing is unstable due to the fact that the routers announce only the number of hop counts to the destination without actually defining the path that leads to that (98) . A router that receives a distance vector advertisement packet may be fooled if the shortest path is actually calculated through the receiving router itself. Link (99) routing is also not a good candidate for inter-autonomous system routing because an Internet is usually too big for this routing method. To use link state routing for the whole internet would require each router to have a huge link state database. It would also take a long time for each router to calculate its rousting (100) using the Dijkstra algorism.

A:path B:hop C:route D:packet

Border Gateway Protocol(BGP) is inter-autonomous system （1）protocol. BGP is based ona routing method called path vector routing. Distance vector routing is not a good candidate for inter-autonomoussystem routing because there are occasions on which the route with the smallest （2） count is not thepreferred route. For example, we may not want a packet through an autonomous system that is not secure eventhough it is shortest route. Also, distance vector routing is unstable due to the fact that the routers announce onlythe number of hop counts to the destination without defining the path that leads to that （3）. A router thatreceives a distance vector advertisement packet may be fooled if the shortest path is actually calculated throughthe receiving router itself. Link （4）routing is also not a good candidate for inner-autonomous system routingbecause an internet is usually too big for this routing method. To use link state routing for the whole internetwould require each router to have a huge link state database. It would also take a long time for each router tocalculate its routing （5）using the Dijkstra algorism.

A:path B:hop C:route D:packet

Border Gateway Protocol (BGP) is inter-autonomous system (71) protocol. BGP is based on a routing method called path vector routing. Distance vector routing is not a good candidate for inter-autonomous system routing because there are occasions on which the route with the smallest (72) count is not the preferred route. For example, we may not want a packet through an autonomous system that is not secure even though it is the shortest route. Also, distance vector routing is unstable due to the fact that the routers announce only the number of hop counts to the destination without actually defining the path that leads to that (73) . A router that receives a distance vector advertisement packet may be fooled if the shortest path is actually calculated through the receiving router itself. Link (74) routing is also not a good candidate for inter-autonomous system routing because an internet is usually too big for this routing methoD. To use link state routing for the whole internet would require each router to have a huge link state database. It would also take a long time for each router to calculate its routing (75) using the Dijkstra algorism.

A:path B:hop C:route D:packet

Border Gateway Protocol(BGP) is inter-autonomous system ______ protocol. BGP is based ona routing method called path vector routing. Distance vector routing is not a good candidate for inter-autonomoussystem routing because there are occasions on which the route with the smallest ______ count is not thepreferred route. For example, we may not want a packet through an autonomous system that is not secure eventhough it is shortest route. Also, distance vector routing is unstable due to the fact that the routers announce onlythe number of hop counts to the destination without defining the path that leads to that ______. A router thatreceives a distance vector advertisement packet may be fooled if the shortest path is actually calculated throughthe receiving router itself. Link ______ routing is also not a good candidate for inner-autonomous system routingbecause an internet is usually too big for this routing method. To use link state routing for the whole internetwould require each router to have a huge link state database. It would also take a long time for each router tocalculate its routing ______ using the Dijkstra algorism.

A:path B:hop C:route D:packet

网络配置如下图所示，为路由器Route1配置访问以太网2的命令是（）。  

A:ip route 192.1.10.60 255.255.255.192 192.200.10.6 B:ip route 192.1.10.65 255.255.255.26 192.200.10.6 C:ip route 192.1.10.64 255.255.255.26 192.200.10.65 D:ip route 192.1.10.64 255.255.255.192 192.200.10.6

Border Gateway Protocol(BGP) is inter-autonomous system （71） protocol. BGP is based on a routing method called path vector routing. Distance vector routing is not a good candidate for inter-autonomous system routing because there are occasions on which the route with the smallest （72） count is not the preferred route. For example, we may not want a packet through an autonomous system that is not secure even though it is shortest route. Also, distance vector routing is unstable due to the fact that the routers announce only the number of hop counts to the destination without defining the path that leads to that （73） . A router that receives a distance vector advertisement packet may be fooled if the shortest path is actually calculated through the receiving router itself. Link （74） routing is also not a good candidate for inner-autonomous system routing because an internet is usually too big for this routing method. To use link state routing for the whole internet would require each router to have a huge link state database. It would also take a long time for each router to calculate its routing （75） using the Dijkstra algorism.

A:path B:hop C:route D:packet

For（）service, we need a virtual-circuit subnet. Let us see how that works. The idea behind virtual circuits is to avoid having to choose a new（）for every packet sent. Instead, when a connection is established, a route from the（）machine to the destination machine is chosen as part of the connection setup and stored in tables inside the（）That route is used for all traffic flowing over the connection, exactly the same way that the telephone system works. When the connection is released, the virtual circuit is also terminated. With connection-oriented service, each packet carries an（）telling which virtual circuit it belongs to.

A:source B:route C:destination D:host