12) which protocols can netbios bind to? (select all that are applicable.) (netbios可以绑定在哪个协议上，选择所有可能的协议)？
a. appletalk
b. ipx
c. ip
d. netbeui
13) what layers do not exist in the tcp/ip model that are in the osi model (哪层不在t c p / i p模型中，但它在o s i模型中)？
a. application, presentation, and network
b. presentation, session, and data link
c. session, network, and physical
d. presentation, data link, and physical
14) what is a socket in the transport layer (传输层中的套接字是什么)？
a. the socket is an ip address plus a port
b. an api that makes the transport layer independent
c. an api that allows multiple applications to share a network connection
d. a function that makes remote procedures appear to be local
15) what is a port (什么是端口)？
a. an api that makes the transport layer independent
b. an api that allows multiple applications to share a network connection
c. a function that makes remote procedures appear to be local
d. the point where upper-layer processes access transport layer services
16) which of the following services uses a process called windowing (下面的哪一个服务使用了所谓的窗口机制)？
a. reliable data transfer
b. connection-oriented virtual circuit
c. buffered transfer
d. resequencing
e. multiplexing
f. efficient, full-duplex transmission
g. flow control
17) what is udp (什么是u d p )？
a. an api that makes the transport layer independent
b. a connectionless, unreliable transport protocol
c. an api that allows multiple applications to share a network connection
d. a function that makes remote procedures appear to be local
18) what is ip (什么是i p )？
a. it is the transport mechanism for upper layer services
b. it is the session layer api for making the transport layer independent