A. Trunk 端口的PVID 值默认为1，并可以修改 B. Trunk 端口接收到数据帧时，当检查到数据帧不带有VLAN ID 时，数据帧在端口加上相应的PVID 值作为VLAN ID C. Trunk 链路可以承载带有不同VLAN ID 的数据帧 D. 在Trunk 链路上传送的数据帧都是带VLAN ID 的
The Internet is based on connectionless end-to-end packet service, which traditionally provided best-effort means of data （ ）using the Transmission Control Protocol/Internet Protocol Suite. Although the （ ）design gives the Internet its flexibility and robustness, its packet dynamics also make it prone to congestion problems,especially at （ ）that connect networks of widely different bandwidths.The initial QoS function set was for internet hosts.One major problem with expensive wide-area（ ）links is the excessive overhead due to small Transmission Control Protocol packets created by applications such as telnet and rlogin. The Nagle （请作答此空），which solves this issue,is now supported by all IP host implementations. A.technology B.problem C.structure D.algorithm
