# Ch07 IPv6 Socket
>###### tags: `Network Programming`

## IPv4 Addressing Temporary Solution
1. Subnetting
2. CIDR(Classless Interdomain Routing)
3. DHCP(Dynamic Host Configuration Protocol)
4. NAT(Network Address Translation)

>More Info:
>https://www.cisco.com/c/en/us/support/docs/ip/routing-information-protocol-rip/13788-3.html#anc0
>https://www.jannet.hk/network-address-translation-nat-zh-hant/

## IPv4 Original Design
1. Variable Header Length(Options field)
2. Check Redundancy Check(Fragmentation Offset field)
3. Maximum Transmission Unit

## IPv6 Design
1. fixed header length - 40 bytes
2. src and dst address - 128 bits
3. extension header for IPv6 protocol options