OSPF Packet Header
(RFC 2328 section A.3.1 page 190)
| Field | Bits | Description |
|---|---|---|
| Version | 8 | Indicates the OSPF protocol version used for the packet, ensuring compatibility and determining processing. 2 means IPv4 and 3 is IPv6 |
| Type | 8 | Specifies the type of OSPF packet, categorizing packets into types like Hello(1), DBD(2) (Database Description), LS Request(3), LS Update(4), and LS Acknowledgment(5). |
| Packet Length | 16 | Indicates the total length of the OSPF packet, including the OSPF header and its contents, ensuring complete packet parsing. |
| Router ID | 32 | Represents the Router ID of the sender, essential for identifying the packet's source and various OSPF processes. |
| Area ID | 32 | Designates the OSPF area to which the sender belongs, assisting in the appropriate area for packet processing. |
| Checksum | 16 | Used for error-checking the OSPF packet header, detecting errors or corruption during header transmission. |
| Auth Type | 8 | Specifies the authentication mechanism used for the OSPF packet, including plaintext, MD5, and others. |
| Authentication | 64 | Conveys authentication information based on the specified authentication type, enabling packet authentication and integrity verification. |