单项选择题
You have been asked to use a 30 bit subnet mask to segment the following network block: 108.12.5.0. How many useable subnetworks and usable hosts could be created?（）
A.32 networks with 8 hosts B.62 networks with 2 hosts C.30 networks with 16 hosts D.32 networks with 14 hosts
多项选择题 Which three steps are part of the PPP CHAP 3-way handshake?（）
多项选择题 Which two parameters are determined during PPP LCP negotiation?（）
多项选择题 Which two protocols are connection-oriented?（）
