IP address works on the ________ layer of the OSI module.

ommodates addresses that refer to a group of hosts on one or more networks. Such addresses are referred to as multicast addresses, and the act of sending a packet from a source to the members of a （1）group is referred to as multicasting. Multicasting done （2）the scope of a single LAN segment is straightforward. IEEE 802 and other LAN protocols include provision for MAC-level multicast addresses. A packet with a multicast address is transmitted on a LAN Segment. Those stations that are members of the （3）multicast group recognize the multicast address and （4）the packet. In this case, only a single copy of the packet is ever transmitted. This technique works because of the （5）nature of a LAN: A transmission from any one station is received by all other station on the LAN.

A.numerous

B.only

C.single

D.multicast@@@SXB@@@A.within

B.out of

C.beyond

D.cover@@@SXB@@@A.different

B.unique

C.special

D.corresponding@@@SXB@@@A.reject

B.accept

C.discard

D.transmit@@@SXB@@@A.multicast

B.unicast

C.broadcast

D.multiple unicast

【填空题】Each Internet （1）, called a host, is independent. Its operators can choose which （2） services to use and which （3） services to make available to the （4） Internet community. Remarkably, this anarchy by design works exceedingly well. IP is responsible for moving packet of data from （5） to node. IP forwards each packet based on a four-byte destination （6） (the IP address). The Internet authorities assign ranges of numbers to different organizations, The organizations （7） groups of their numbers to departments. （8） is responsible for verifying the correct delivery of data from （9） to server. Data can be lost in the intermediate （10）. TCP adds support to detect error or lost data and to trigger retransmission until the data is correctly and completely received.

dern English literature？

A．Narration through second-person address

B．Novel structure based on real-time chronology

C．Linguistic experimentation

D．Literary realism concerning physical reality

E．Stream of consciousness

A、IP address

B、IP address:5901

C、IP address::5901

文中（3 ）处正确的答案是（）。

A．Email address and IP address

B．MAC address and port address

C．MAC address and IP address

D．port number and IP address

A. IP Address for Signaling

B. IP Address for Traffic

C. IP Address for O&M

D. IP Address for Backup

A．Email address and IP address

B．MAC address and port address

C．MAC address and IP address

D．port number and IP address

A socket is composed of two addresses:(72)。

A．MAC address and IP address

B．MAC address and port address

C．port number and IP address

D．E-mail address and IP address

A．broadcast address

B．multiple address

C．host address

D．subnet mask

A．MAC address and IP address

B．MAC address and port address

C．E-mail address and IP address

D．port number and IP address