【正文】
類 ( Class of IP Address) 3. 保留和私有地址( Reserved and Private IP Address) 4. 網(wǎng)絡掩碼和子網(wǎng)劃分( Network Mask and Subting ) 5. 可變長度子網(wǎng)掩碼( VLSM ) 6. 匯總和 CIDR( Summarization and CIDR) 169。 2020, Shenzhen Polytechnic. All rights reserved. . 5 IP地址結構( Structure of IP Address) 169。 2020, Shenzhen Polytechnic. All rights reserved. . 9 C類地址( Class C) 地址范圍: 192~223 Address Range:192223 169。 An IP address that has binary 0s in all bit positions is reserved for default route 1地址 ,表示泛洪廣播 An IP address that has binary 0s in all bit positions is reserved for flood broadcast 169。 2020, Shenzhen Polytechnic. All rights reserved. . 15 網(wǎng)絡掩碼( Network Mask) A類: B類: C類: 169。 2020, Shenzhen Polytechnic. All rights reserved. . 18 劃分子網(wǎng)原因( Reasons for Subting) 1. 提供靈活的編址 Provides addressing flexibility Provides 2. 提供廣播抑制 Broadcast Containment 3. 為 LAN提供低水平的安全 Lowlevel security on the LAN. 169。 2020, Shenzhen Polytechnic. All rights reserved. . 22 實例 1: C類地址 2位子網(wǎng)化 ( Two Bits Subting for Class C ) 子網(wǎng)號( Sub) 地址范圍( range) 00 000000 0 00000001~00111111 1~62 其中 :0為網(wǎng)絡地址, 63為廣播地址 01 000000 64 01000001~01111111 65~127 其中 :64為網(wǎng)絡地址, 127為廣播地址 10 000000 128 10000001~10111111 129~191 其中 :128為網(wǎng)絡地址, 191為廣播地址 11 000000 192 11000001~11111111 193~255 其中 :192為網(wǎng)絡地址, 255為廣播地址 169。 2020, Shenzhen Polytechnic. All rights reserved. . 26 Written Exercise: Sub Masks Address Sub Mask Class Sub 169。 2020, Shenzhen Polytechnic. All rights reserved. . 30 Case Study: Sub Programming Other subs 30 hosts per sub Class C address: 169。 2020, Shenzhen Polytechnic. All rights reserved. . 34 . 64/27 ? 將沒有使用的掩碼長度為 27的子網(wǎng)進一步劃分為掩碼長度為 30 – Sub with one mask at first (/27) – Further sub one of these subs not used elsewhere (/30) C B A HQ 可變長度子網(wǎng)掩碼( VariableLength Sub Mask) 169。 2020, Shenzhen Polytechnic. All rights reserved. .