1)若要將一個B類的網絡172.17.0.0劃分為14個子網，請計算出每個子網的子網掩碼，以及在每個子網中主機IP地址的范圍是多少？
答：子網掩碼是255.255.240.0
每個子網的網絡地址：
172.17.16.0
172.17.32.0
172.17.48.0
172.17.64.0
172.17.80.0
172.17.96.0
172.17.112.0
172.17.128.0
172.17.144.0
172.17.160.0
172.17.176.0
172.17.192.0
172.17.208.0
172.17.224.0
每個子網主機IP的地址：
172.17.16.1~172.17.31.254
172.17.32.1~172.17.47.254
172.17.48.1~172.17.63.254
172.17.64.1~172.17.79.254
172.17.80.1~172.17.95.254
172.17.96.1~172.17.111.254
172.17.112.1~172.17.127.254
172.17.128.1~172.17.143.254
172.17.144.1~172.17.159.254
172.17.160.1~172.17.175.254
172.17.176.1~172.17.191.254
172.17.192.1~172.17.207.254
172.17.208.1~172.17.223.254
(2)將一個C類的網絡192.168.25.0劃分為6個子網，請計算出子網掩碼、每個子網的網絡地址，以及在每個子網中主機IP地址的范圍，
子網劃分知識
。答 :子網掩碼:255.255.255.22
網絡地址:
192.168.25.160
192.168.25.192
192.168.25.96
192.168.25.128
192.168.25.64
192.168.25.32
主機地址的范圍:
192.168.25.161~192.168.25.190
192.168.25.193~192.168.25.222
192.168.25.97~192.168.25.126
192.168.25.129~192.168.25.158
192.168.25.65~192.168.25.94
192.168.25.33~192.168.25.62
(3) 若要將一個B類的網絡172.17.0.0劃分子網，其中包括3個能容納16000臺主機的子網，7個能容納2000臺主機的子網，8個能容納254臺主機的子網，請寫出每個子網的子網掩碼和主機IP地址的范圍，
電腦資料
《子網劃分知識》(http://salifelink.com)。答：子網掩碼分別是：255.255.192.0，255.255.224.0,255.255.255.0
網絡地址 主機地址范圍
172.17.0.0/18 172.17.0.1~172.17.63.254
172.17.64.0/18 172.17.64.1~172.17.127.254
172.17.128.0/18 172.17.128.1~172.17.191.254
172.17.192.0/18 172.17.192.1~172.17.199.254
172.17.192.0/21 172.17.192.1~172.17.199.254
172.17.200.0/21 172.17.200.1~172.17.207.254
172.17.208.0/21 172.17.208.1~172.17.215.254
172.17.216.0/21 172.17.216.1~172.17.223.254
172.17.224.0/21 172.17.224.1~172.17.231.254
172.17.232.0/21 172.17.232.1~172.17.239.254
172.17.240.0/21 172.17.240.1~172.17.247.254
172.17.248.0/21 172.17.248.1~172.17.248.254
172.17.248.0/24 172.17.248.1~172.17.248.254
172.17.249.0/24 172.17.249.1~172.17.249.254
172.17.250.0/24 172.17.250.1~172.17.250.254
172.17.251.0/24 172.17.251.1~172.17.251.254
172.17.252.0/24 172.17.252.1~172.17.252.254
172.17.253.0/24 172.17.253.1~172.17.253.254
172.17.254.0/24 172.17.254.1~172.17.254.254
172.17.255.0/24 172.17.255.1~172.17.255.254