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OSPFv2 (ospfv2)

Reached from

Lower layerSelectorValue
ipv4protocol89 (0x59)

Fields

FieldTypeDefaultAutoDescription
versionuint(8)2OSPF version (2 = OSPFv2, 3 = OSPFv3).
typeenum(8)1 (hello)Protocol number of the next layer (see Next layer)OSPF packet type (Hello / DB Description / LS Request / LS Update / LS Ack; Auto from the next layer).
packet_lengthuint(16)Length of the header and payload in octetsLength of the OSPF packet including the header, in octets (Auto).
router_idipv4192.0.2.1Router ID of the sending router.
area_idipv40.0.0.0Area the packet belongs to (0.0.0.0 = backbone).
checksumuint(16)Internet checksum over the header and everything after it; authentication counted as zeroInternet checksum over the OSPF packet without the authentication field (Auto).
au_typeenum(16)0 (null)Authentication type (0 = null, 1 = simple password, 2 = cryptographic).
authenticationbytes(8)00 00 00 00 00 00 00 0064-bit authentication field (password, or key id / sequence for cryptographic auth).

type

ValueName
1 (0x01)hello
2 (0x02)db_description
3 (0x03)ls_request
4 (0x04)ls_update
5 (0x05)ls_ack

au_type

ValueName
0 (0x0000)null
1 (0x0001)simple_password
2 (0x0002)cryptographic

Next layer

The next layer is selected by type; when the field is Auto the builder writes the value of the protocol stacked above.

ValueProtocolNote
1 (0x01)ospfv2_hello
2 (0x02)ospfv2_dbd
3 (0x03)ospfv2_lsr
4 (0x04)ospfv2_lsu
5 (0x05)ospfv2_lsack

Constraints

LevelRule
warningversion = 2

Sample templates