Forwarding tables in hosts C:\>netstat -rn Route Table 工 nterface lis七 MS TCP Loopback interface 0x2...00096bda2ac6 Intel(R)PRo/100 VE Network Connection-Packet Scheduler Miniport Ac七 ive routes: Ne七 work Destination Netmask Gateway 工 nterface Metrio 158.132.10.28158.132.11.140 20 127.0.0.0 255.0.0.0 127.0.0.1 127.0.0.1 158.132.10.0 255.255.254.0158.132.11.140158.132.11.140 20 158.132.11.140255.255.255.255 127.0.0.1 1270.0.1 158.132.255.255255.255.255.255158.132.11.140158.132.11.140 20 224.0.0.0 240.0.0.0158.132.11.140158.132.11.140 20 255.255.255.255255.255.255.255158.132.11.140158.132.11.140 Default Gateway 158.132.10.28 Persistent routes None 11
11 Forwarding tables in hosts C:\>netstat -rn Route Table =========================================================================== Interface List 0x1 ........................... MS TCP Loopback interface 0x2 ...00 09 6b da 2a c6 ...... Intel(R) PRO/100 VE Network Connection - Packet Scheduler Miniport =========================================================================== =========================================================================== Active Routes: Network Destination Netmask Gateway Interface Metric 0.0.0.0 0.0.0.0 158.132.10.28 158.132.11.140 20 127.0.0.0 255.0.0.0 127.0.0.1 127.0.0.1 1 158.132.10.0 255.255.254.0 158.132.11.140 158.132.11.140 20 158.132.11.140 255.255.255.255 127.0.0.1 127.0.0.1 20 158.132.255.255 255.255.255.255 158.132.11.140 158.132.11.140 20 224.0.0.0 240.0.0.0 158.132.11.140 158.132.11.140 20 255.255.255.255 255.255.255.255 158.132.11.140 158.132.11.140 1 Default Gateway: 158.132.10.28 =========================================================================== Persistent Routes: None
onfig -all Ethernet adapter Local Area Connection Connection-specific DNS Suffix comp polyu. edu. hk Description Intel(R)PRo/100 VE Network Physical Address 00-09-6B-DA-2A-C6 Dhcp Enabled Yes Autoconfiguration Enabled Yes 工 p Address :158.132.11.140 Subnet mask :255.255.254.0 Default Gat 158.132.10.28 DHCP Server :158.132.10.210 DNS Servers 158.132.10.4 158.132.8.3 158.132.8.4 158.132.10.3 Primary WINS Server :158.132.18.106 Secondary WINS Server 158.132.18.105 Lease obtained Monday 26 September Monday, 26 September 12
12 C:\>ipconfig -all Ethernet adapter Local Area Connection: Connection-specific DNS Suffix . : comp.polyu.edu.hk Description . . . . . . . . . . . : Intel(R) PRO/100 VE Network … Physical Address. . . . . . . . . : 00-09-6B-DA-2A-C6 Dhcp Enabled. . . . . . . . . . . : Yes Autoconfiguration Enabled . . . . : Yes IP Address. . . . . . . . . . . . : 158.132.11.140 Subnet Mask . . . . . . . . . . . : 255.255.254.0 Default Gateway . . . . . . . . . : 158.132.10.28 DHCP Server . . . . . . . . . . . : 158.132.10.210 DNS Servers . . . . . . . . . . . : 158.132.10.4 158.132.8.3 158.132.8.4 158.132.10.3 Primary WINS Server . . . . . . . : 158.132.18.106 Secondary WINS Server . . . . . . : 158.132.18.105 Lease Obtained. . . . . . . . . . : Monday, 26 September, … Lease Expires . . . . . . . . . . : Monday, 26 September, …
Forwarding tables in hosts 13 口Ahos' s view about the“ outside world” is binary: either local or nonlocal a In the local case it sends datagrams to the destination directly. a In the nonlocal case, it sends datagrams to a default router a In both cases the host uses arp cache or arp to find out the corresponding mac addresses
Forwarding tables in hosts 13 A host’s view about the “outside world” is binary: either local or nonlocal. In the local case, it sends datagrams to the destination directly. In the nonlocal case, it sends datagrams to a default router. In both cases, the host uses ARP cache or ARP to find out the corresponding MAC addresses
An example(/24 for all subnets 14 to the internet R5 8 8 营R1| 192]01.1 202H 132.12.1.0 132.12.2.0 131.101.3 R3 R4 131.10.128.0131.10.129.0 131.10.10.0 131.1090
An example (/24 for all subnets) 14
R1’ s forwarding table Destinations Masks Gateways Comments 127.0.0.1 255255.2552551270.0.1 Loopback driver 192.10.1.2255.255.255.255192.10.1 Host specific route 131.10.1.0255255.255.0 131.10.1.1 Directly connected net 192.12350255255.2550192.12.35.1 Directly connected net 193.1.1.0 255255255.0 193.1.1.1 Directly connected net 131.10.128.0255255.2550 131.10.1.2 Route to a gateway 131.10.12902552552550131.10.1.2 Route to a gateway 131.10.10.0255255255.0131.10.1.3 Route to a gateway 131.10.90255255255.0131.10.1.3 Route to a gateway 132.12.0.0255255.2550 192.12 35.2 Route to a gateway Default 0.0.0.0 193.1.12 Default router
R1’s forwarding table 15 Destinations Masks Gateways Comments 127.0.0.1 255.255.255.255 127.0.0.1 Loopback driver 192.10.1.2 255.255.255.255 192.10.1.1 Host specific route 131.10.1.0 255.255.255.0 131.10.1.1 Directly connected net. 192.12.35.0 255.255.255.0 192.12.35.1 Directly connected net. 193.1.1.0 255.255.255.0 193.1.1.1 Directly connected net. 131.10.128.0 255.255.255.0 131.10.1.2 Route to a gateway 131.10.129.0 255.255.255.0 131.10.1.2 Route to a gateway 131.10.10.0 255.255.255.0 131.10.1.3 Route to a gateway 131.10.9.0 255.255.255.0 131.10.1.3 Route to a gateway 132.12.0.0 255.255.255.0 192.12.35.2 Route to a gateway Default 0.0.0.0 193.1.1.2 Default router