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Address Resolution. The process of mapping protocol addresses to hardware addresses Only addresses on the same network as the host are resolved Remote addresses are never resolved. Address Resolution. Address Resolution Techniques. Table Look up Closed-Form Computation Message Exchange.
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Address Resolution • The process of mapping protocol addresses to hardware addresses • Only addresses on the same network as the host are resolved • Remote addresses are never resolved
Address Resolution Techniques • Table Look up • Closed-Form Computation • Message Exchange
Address Resolution with Table Lookup IP ADDRESS HARDWARE ADDRESS 197.15.3.2 0A:07:4B:12:82:36 197.15.3.3 0A:08:23:32:4C:44 197.15.3.4 0A:00:44:24:5D:EF 197.15.3.5 0A:32:86:23:E3:C1
Address Resolution with Closed-Form Computation • Usually used where hardware addresses are configurable • Usually a simple formula is used to compute the last part of the hardware address from the host part of the Protocol address • ex. IP addr= 192.168.2.44 -> 01-02-03-04-05-44
Address Resolution with Message Exchange • Distributed approach • Host send out a message with the request and receives back a reply • Two configurations: server and individual
Address Resolution Protocol • Table lookup is usually used to resolve WAN addresses • Closed-form is used on configurable networks • Message exchange is used on LANs with static addressing • ARP is part of the TCP suite - standard • Two type messages defined: request & reply