Intra-domain routing Dan li CS Department, Tsinghua University 2021/2/8
Intra-domain routing 2021/2/8 1 Dan LI CS Department, Tsinghua University
Today's Lecture Routing Model Intra-domain Routing 2021/2/8
Today’s Lecture Routing Model Intra-domain Routing 2021/2/8 2
Notion of an Internet protocol How is it possible to send bits across incompatible LANs and wans? Solution: protocol software running on each host and router smooths out differences between different networks Implements an internet protocol(i.e, set of rules that governs how hosts and routers should cooperate when they transfer data from network to network TCP /IP is protocol (family) for global P Internet
Notion of an Internet Protocol How is it possible to send bits across incompatible LANs and WANs? Solution: protocol software running on each host and router smooths out differences between different networks Implements an internet protocol (i.e., set of rules) that governs how hosts and routers should cooperate when they transfer data from network to network • TCP/IP is protocol (family) for global IP Internet
What does an Internet protocol do? Provides naming scheme k Defines uniform format for host addresses Each host (and router) is assigned at least one internet address that uniquely identifies it Provides delivery mechanism An internet protocol defines a standard transfer unit packet) Packet consists of header and payload Header: contains info such as packet size source and destination addresses Payload: contains data bits sent from source host Encapsulation- key to network messages
What Does an Internet Protocol Do? Provides naming scheme Defines uniform format for host addresses Each host (and router) is assigned at least one internet address that uniquely identifies it Provides delivery mechanism An internet protocol defines a standard transfer unit (packet) Packet consists of header and payload Header: contains info such as packet size, source and destination addresses Payload: contains data bits sent from source host Encapsulation - key to network messages
Transferring Data via Internet Host a Host B client server (1)data (8) data protocol protocol intenetpacket software software (2) dataPH (7) dataPH ant LAN2 Frame adapter Router adapter (3)data PH FH1 LAN2 ) data PH FH2 LAN1 LAN1 adapter adapter LAN2 frame LAN2 data PH! FH1 data PH FH2(5) protocol software
Transferring Data via Internet protocol software client LAN1 adapter Host A data data PH FH1 data PH data PH FH2 LAN1 LAN2 data data PH data PH FH2 (1) (2) (3) (4) (5) (6) (7) (8) internet packet LAN2 frame protocol software LAN1 adapter LAN2 adapter Router FH1 data PH protocol software server LAN2 adapter Host B Frame