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Addressing (or: the sublime joy of base conversion). But first… On the difference between a “port” and a “port”. Port: A physical interface on a router or switch on which packets arrive and/or depart. Port: A number used by transport protocols to determine which process to give a packet to.
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Port: A physical interface on a router or switch on which packets arrive and/or depart
Port: A number used by transport protocols to determine which process to give a packet to Does not refer to anything physical!
Addressing in the Postal Service • How can the postal service determine how to route mail? • Simple: each post office stores an entry for every person • Post office in San Francisco: mail for “Kay Ousterhout” should be sent towards Berkeley • Post office in Berkeley: mail for “Kay Ousterhout” should be sent towards Soda Hall • … • What’s wrong with this strategy?
Addressing in the Postal Service Person in 419: Place mail on Kay’s desk Post office in Berkeley: sent to Soda Hall Kay Ousterhout 419 Soda Hall Berkeley, CA 94709 Mail room in Soda: send to office 419 Post office in San Francisco: send to 94709
Addressing “Kay Ousterhout” 419 Soda Hall Berkeley, CA 94709 MAC Address IP Address