Networking Review w What is a network? a system of lines/channels that interconnect nodes *E.g., railroad, highway, telephony network, computer network What is a computer network? k a form of communication network moves information Nodes are general-purpose computers 2021/2/1 16
Networking Review What is a network? 2021/2/1 16 A system of lines/channels that interconnect nodes E.g., railroad, highway, telephony network, computer network What is a computer network? A form of communication network — moves information Nodes are general-purpose computers
A Taxonomy of Communication Networks Communication Network Broadcast Switcher Communication Communication Network Network 2021/2/1
A Taxonomy of Communication Networks Communication Network Switched Communication Network Broadcast Communication Network 2021/2/1 17
Broadcast vs Switched broadcast communication networks Information transmitted by any node is received by every other node in the network k Problem coordinate the access of all nodes to the shared communication medium(Multiple Access Problem) A D 口口口口口 2021/2/1
Broadcast vs. Switched Broadcast communication networks Information transmitted by any node is received by every other node in the network Problem: coordinate the access of all nodes to the shared communication medium (Multiple Access Problem) 2021/2/1 18 A B C D E
Broadcast Vs Switched(Cont) Switched communication networks k Information is transmitted to a sub-set of designated nodes Example: WAN k Problem how to forward information to intended node(s) B 2021/2/1
Broadcast vs. Switched (Cont.) Switched communication networks Information is transmitted to a sub-set of designated nodes Example: WAN Problem: how to forward information to intended node(s) 2021/2/1 19 A B A’ B’
Multiplexing in Switched Network Need to share network resources Conversation 1: A->B Conversation 2:c->D How? Con 1 gets the forwarding resource of a sometimes Con. 2 gets the forwarding resource of a sometimes 2021/2/1 20
Multiplexing in Switched Network Need to share network resources Conversation 1: A->B Conversation 2: C->D How? Con. 1 gets the forwarding resource of A’ sometimes Con. 2 gets the forwarding resource of A’ sometimes 2021/2/1 20 A B C D A’