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IP and Routing. inheaven@sparcs.kaist.ac.kr Dep. of CS in KAIST. Overview. Introduction to network IP - Internet Protocol IP Routing. class A. class B. class C. class D. class E. Introduction to network I. Four layer of network. Internet Addresses. Introduction to network II.
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IP and Routing inheaven@sparcs.kaist.ac.kr Dep. of CS in KAIST
Overview • Introduction to network • IP - Internet Protocol • IP Routing
class A • class B • class C • class D • class E Introduction to network I • Four layer of network • Internet Addresses
Introduction to network II • Encapsulation
Introduction to network III • Ehternet Encapsulation • MTU
IP - Internet Protocol I • Character • Unreliable • Connectionless • IP header
IP - Internet Protocol II • Header length • number of 32-bit words in the header • TTL (Time To Live) • sets an upper limit on the number of routers through which a datagram can pass • TOS (Type of Service) Field • 3-bit precedence field (which is ignored today) • 4 TOS field • unused bit (that must be 0)
IP - Internet Protocol III • 4 TOS Field
IP - Internet Protocol IV • Subnet mask • To know how many bits are for host ID • One bits for the network ID and subnet ID • Zero bits for the host ID • Special Case IP Addresses
IP Routing I • Routing table • destination IP address • next-hop router • Flags • Specification of network interface • Routing Principles • Search for a matching host address • Search for a matching network address • Serch for a default entry
IP Routing II • ICMP (Internet Control Message Protocol) • Communicates error messages and other conditions.
host (1)IP datagram (3)ICMP redirect (2)IP datagram R1 R2 IP Routing III • ICMP Redirect Errors • Example of an ICMP redirection
IP Routing IV • Format of the ICMP redirect message
IP Routing V • ICMP Router Discovery Messages • initialize a routing table • concept • broadcast(or multicast) router solicitation message • routers respond with a router advertisements message • Format of router solicitation message
IP Routing VI • Format of router advertisement message
References • TCP/IP Illustrated by W. Richard Stevens