Which packet is sent in response to a BGP Open packet？（）

A.Start Tunnel Discovery Request

B.Start Control Connection Request

C.L2TP Control Connection Request

D.L2TP Tunnel Establishment Request

A.A

B.B

C.C

D.D

A. Layer 2 TTL

B. Layer 3 TTL

C. Layer 3 source address

D. Layer 3 destination address

A. If a packet is sent to a multicast group address, the multicast frame contains the source multicast address.

B. A router does not have to be a member of a multicast group to recei ve multicast data.

C. A router must be a member of a multicast group to send to the group.

D. A router does not have to be a member of a multicast group to send to the group.

E. If a packet is sent to a multicast group address, all members of the multic ast group will receive it.

F. A router must be a member of a multicast group to receive multicast data.

A. Excluded traffic is not accelerated.

B. Excluded traffic is only compressed.

C. Source/destination filter applies to all traffic sent from LAN to WAN.

D. Source/destination filters work in packet interception mode using RIPv2.

A. The source device will only retransmit lost packets on the request of the destination device.

B. The source device starts a timer when it sends a segment and retransmits if an acknowledgment is not received before the timer expires.

C. The destination device acknowledges receipt of a segment by sending a packet with a new sequence number and the ACK bit sent.

D. The destination device acknowledges receipt of a segment by sending a packet that indicates the next sequence number it expects.

E. If the destination device does not receive a segment, all segments are retransmitted.

F. The source device keeps a record of all segments sent and expects and acknowledgment of each.

A.The MISMERGE of TMP maintenance node means the MEG ID of CV frame. received does not match the local MEG ID.

B.Loss of connectivity of TMP maintenance node means the CV frame. sent by the peer MEP is not received within three and a half frame. periods.

C.The service layer signal being invalid of TMP maintenance node means a fault occurs in the upstream service layer, including LOC, MISMERGE, unexpected MEP and LCK, and the service layer inserts FDI message into the adjacent client layer. The client layer reports the SSF alarm after receiving the FDI message.

D.Unexpected CV packet period of TMC maintenance node means the MEG ID of the received CV frame. does not match the local MEG ID.

A.0

B.1

C.2

D.3

E.4

A. to validate packet receipt on interfaces where the traffic should be received

B. to forward packets out the interfaces where the traffic should be received

C. to forward packets out the interfaces where the traffic should be sent

D. to validate packet receipt on interfaces where the traffic should be sent

s the sending of voice signals over an IP-based network, such as the Internet. The practice of making telephone calls over the internet has had a number of different names, including packet voice, voice over packet, voice over the internet, internet telephone, and Voice over Ip（Voip）. But it appears the industry has settled on the term”Voice ove IP” in reference to the internet protocol, which controls the transfer of data over the internet. There are currently three ways to deliver VoIp to users, the first technique is found at the corporate level. Many companies are offering VoIP systerms that operate over a local area network. These systems involve a fair amount of equipment, such as VoIP servers, special IP-enabled telephones, and routers that can direct telephone calls. Today a large portion of corporate sites have converted their older internal telephone systems to VoIP systems that opreate over a LAN, thus converging two systems into one. A second common solution is the one often encountered at home. Using existing telephones, a special converter is added between the telephone and a high speed internet（DSL or cable modem）connection. The converter digitizes the voice signal and creates a stream of packets that are then sent over an ip connection.The third technique involves smart cell phones. Never cell technologies are all packet-based, thus requiring a telephone call to be converted to digital packets and sending those packets over IP networks.】

From the paragraph above，a popular service that has attracetd the interest of companies and home users,is termed as （） . The data transfer over the Internet is controlled by the （） . At corporate level, many companies have replaced their older internal telephone systerms with （） that oprerate over a local area network.

A、voice over the internet B、voice over packet C、Voice over IP D、internet telephony A、packet B、internet protocol C、industry D、VoIp servers A、VoIP systems B、IP-enablde telephones C、VoIP servers D、routers