IPAddressin IP Addressing 2 32 Bi 少32Bits NETWORK NETWORK HOST 1 Byte 中8Bs+8Bts·8Eits·8Bits 8Bs+·8Bits+·8Bts+8Bts H 204 176 Special Addresses a Private Addresses Special Address NetID HostID Source o Class NeT工TDs Blocks Direct broadcast Address Specific All 1s Destination 10.0.0 172.16to172.31 Limited broadcast Address All is All isDestination 16 This host on this network All Os All OsSource 192.168.0to 56 192.168.255 Specific host on this Os ficDestination Loopback address Subnets and subnet masks Subnets and subnet mask complexity of internetworked CaNS within oragnization OLUTION: Create anothe Insulate ovebers and Tot%, gle network nu a Site looks to rest of internet NETWORK SUBNET HOST Each LAN assigned subnet number Host portion of address partitioned into subnet number and host number HOW ?? Local routers route within subnetted network Subnet mask indicates which bits are subnet y using a SUBNET MASK number and which are host number11 哈工大计算机学院 李全龙 Network Application Development 1: Introduction 61 哈工大计算机学院 李全龙 Network Application Development 1: Introduction 62 哈工大计算机学院 李全龙 Network Application Development 1: Introduction 63 Special Addresses Loopback address 127 Any Destination Specific host on this All 0s Specific Destination network This host on this network All 0s All 0s Source Limited broadcast Address All 1s All 1s Destination Direct broadcast Address Specific All 1s Destination Network Address Specific All 0s None Source or Destination Special Address NetID HostID 哈工大计算机学院 李全龙 Network Application Development 1: Introduction 64 Private Addresses 192.168.0 to 256 192.168.255 C B 172.16 to 172.31 16 A 10.0.0 1 Class NetIDs Blocks 哈工大计算机学院 李全龙 Network Application Development 1: Introduction 65 Subnets and Subnet Masks „ Allow arbitrary complexity of internetworked LANs within organization „ Insulate overall internet from growth of network numbers and routing complexity „ Site looks to rest of internet like single network „ Each LAN assigned subnet number „ Host portion of address partitioned into subnet number and host number „ Local routers route within subnetted network „ Subnet mask indicates which bits are subnet number and which are host number 哈工大计算机学院 李全龙 Network Application Development 1: Introduction 66 Subnets and Subnet Mask