CIS 3210 Lecture Notes - Lecture 28: Network Address Translation, Icann, Ip Address

• School: University of Guelph
• Department: Computing and Information Science
• Course: CIS 3210
• Professor: Xiaodong Lin

Document Summary

A: icann: internet corporation for assigned names and numbers. We can use a single public facing ip address for a home with many devices. Ipv4 will eventually run out of ip addresses available. Motivation: the local network uses just one ip address as far as outside world is connected: Range of addresses not needed from isp: just on ip address for all devices. Can change addresses of devices in local network without notifying the outside world. Can change isp without changing addresses of devices in local network. Devices inside local net not explicitly addressable, visible by outside work (a security plus) Outgoing datagrams: replace (source ip address, port #) of every outgoing package datagram to (nat ip address, new port #) Remote clients/servers will respond using (nat ip, new port #) as dest addr. Remember (in nat translation table) every (source ip address, port #) to (nat ip address, new port #) translation pair.