"Network Layer and Mobile IP" presents of: Network Layer in Internet, Network Layer functions,ID datagram format, ID addressing, subnets, herarchical addressing, network service model, virtual circuits, Datagram networks, Routing Algorithm classification,. | Network Layer and Mobile IP 1 Network Layer in Internet: Big Picture Host, router network layer functions: This image cannot currently be display ed. Transport layer: TCP, UDP routing protocols •path selection Network layer protocol (., IP) Network layer •addressing conventions •packet format •packet handling conventions forwarding Control protocols (. ICMP) •error reporting •router “signaling” Link layer physical layer 2 Network layer functions transport packet from sending to receiving hosts network layer protocols in every host, router three important functions: path determination: route taken by packets from source to dest. Routing algorithms switching: move packets from router’s input to appropriate router output call setup: some network architectures require router call setup along path before data flows application transport network data link physical network data link physical network data link physical network data link physical network data link physical network data link physical network data link physical network data link physical network data link physical application transport network data link physical 3 IP Datagram Format IP protocol version number header length (bytes) “type” of data max number remaining hops (decremented at each router) upper layer protocol to deliver payload to 32 bits type of ver head. len service length fragment 16-bit identifier flgs offset time to upper Internet layer live checksum 32 bit source IP address 32 bit destination IP address Options (if any) . timestamp, record route taken, specify list of routers to visit. total datagram length (bytes) for fragmentation/ reassembly data (variable length, typically a TCP or UDP segment) 4 IP Addressing: introduction IP address: 32-bit identifier for host, router interface interface: connection between host/router and physical link router’s typically have multiple interfaces host typically has one interface IP addresses associated with each interface .
