Webrtc protocol introduction -- an article to understand ice, stun, NAT, turn

If you want to know ICE, You have to understand NAT

NAT

Network address translation （ English ：Network Address Translation, abbreviation ：NAT; Also known as network masking 、IP Masking ） In computer network, it is a kind of IP Rewrite the source when the packet passes through the router or firewall IP Address or purpose IP Address technology . This technology is widely used when there are multiple hosts but only through a public network IP Address access to the private network of the Internet . It is a convenient and widely used technology . Of course ,NAT It also complicates the communication between hosts , It leads to the reduction of communication efficiency .

Why is there a public network IP And lan IP.
We know that because of IPv4 Your address is limited , Therefore, it is impossible to assign a public address to all devices in the world ,NAT Is relief IPv4 A method of address exhaustion .
meanwhile ,NAT It can also ensure the security of LAN devices .

ICE

Interactive connection creation （Interactive Connectivity Establishment）, A comprehensive NAT Crossing technology .

The interactive connection is created by IETF Of MMUSIC Developed by the working group