Two Key Network-Layer Functions ▣forwarding:.move analogy: packets from router's input to appropriate ▣routing:process of router output planning trip from source to dest ▣routing:determine route taken by forwarding:process packets from source of getting through to dest. single interchange o routing algorithms Network Layer 4-5 Network Layer 4-5 Two Key Network-Layer Functions  forwarding: move packets from router’s input to appropriate router output  routing: determine route taken by packets from source to dest.  routing algorithms analogy:  routing: process of planning trip from source to dest  forwarding: process of getting through single interchange