| 0 | 1 | 2 | 3 | 4 | 5 | 6 | 7 | 0 | 1 | 2 | 3 | 4 | 5 | 6 | 7 | 0 | 1 | 2 | 3 | 4 | 5 | 6 | 7 | 0 | 1 | 2 | 3 | 4 | 5 | 6 | 7 |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Version | Traffic CLass | Flow Label | |||||||||||||||||||||||||||||
| Payload Length | Next Header | Hop Limit | |||||||||||||||||||||||||||||
| Source IP Address - routing prefix (first half) | |||||||||||||||||||||||||||||||
| Source IP Address - routing prefix (second half) / 64 | |||||||||||||||||||||||||||||||
| Source IP Address - interface identifier (first half) | |||||||||||||||||||||||||||||||
| Source IP Address - interface identifier (second half) / 128 | |||||||||||||||||||||||||||||||
| Destination IP Address - routing prefix (first half) | |||||||||||||||||||||||||||||||
| Destination IP Address - routing prefix (second half) / 64 | |||||||||||||||||||||||||||||||
| Destination IP Address - interface identifier (first half) | |||||||||||||||||||||||||||||||
| Destination IP Address - interface identifier (second half) / 128 | |||||||||||||||||||||||||||||||
| Options (optional) | |||||||||||||||||||||||||||||||
IPv6 Address Abbreviations
2001:0db8:0000:abcd:0000:0000:0000:0001
becomes
2001:db8:0:abcd:0:0:0:1
[remove leading zeros; replace 0000 groups with :: once]
IPv6 Header Contents
Version (4 bits) Traffic Class (8 bits) First 6 bits = Type of Service; last 2 bits = Explicit Congestion Notification Flow Label (20 bits) used to maiintain packet flow Payload Length (16 bits) Number of bytes in packet; <= 65,535 or 0 if Extension Header is used Next Header Type of Extension Header or Upper Layer PDU Hop Limit(8 bits) same as IPv4 Source Address (128 bits) Destination Address (128 bits)