●   The Border Gateway Protocol （BGP）is an interautonomous system__(71)__protocol.The primary function of a BGP speaking system is to exchange network __(72)__information with other BGP system.This network reachability information includes information on the list of Autonomous System（ASs）that reachability  information  traverses.BGP-4 provides a new set of mechanisms for supporting __(73)__interdomain routing.These mechanisms include support for advertising an IP __(74)__and eliminate the concept of network class within BGP.BGP-4 also introduces mechanisms that allow aggregation of routes， including __(75)__of AS paths.These changes provide support for the proposed supernettting scheme. 

（71）A．connecting    

B．resolving    

C．routing  

D．supernettting  

（72）A．Secubility 

B．reachability    

C．capability  

D．reliability

（73）A．Answerless 

B．Connectionless

C．Confirmless

D．classless

（74）A．prefix  

B．suffix   

C．infix   

D．reflex

（75）A．reservation

B．relation   

C．aggregation

D．connection