References: RFC 4271
| Value | Defined by | Name | Description | References |
|---|---|---|---|---|
| 0 | IANA | Unspecific | - | RFC Errata 4493 |
| 1 | IANA | Unsupported Version Number | - | RFC 4271 |
| 2 | IANA | Bad Peer AS | - | RFC 4271 |
| 3 | IANA | Bad BGP Identifier | - | RFC 4271 |
| 4 | IANA | Unsupported Optional Parameter | - | RFC 4271 |
| 5 | IANA | [Deprecated] | - | RFC 4271 |
| 6 | IANA | Unacceptable Hold Time | - | RFC 4271 |
| 7 | IANA | Unsupported Capability | - | RFC 5492 |
| 8 | IANA | Deprecated | - | RFC 9234 |
| 9 | IANA | Deprecated | - | RFC 9234 |
| 10 | IANA | Deprecated | - | RFC 9234 |
| 11 | IANA | Role Mismatch | - | RFC 9234 |