多项选择题
A. They acknowledge receipt of TCP segments.
B. They guarantee datagram delivery.
C. They can provide hosts with information about network problems.
D. They are encapsulated within IP datagrams.
E. They are encapsulated within UDP datagrams.
多项选择题 Which three address ranges are used for internal private address blocks as defined by RFC 1918?（）
单项选择题 What does the term computer language refer to?（）
单项选择题 Which protocol automates all of the following functions for hosts on a network: IP configuration, IP addresses, subnet masks, default gateways, and DNS server information?（）