AS_TRANS
AS23456
AS23456 is AS_TRANS, the stand-in for 4-byte AS numbers (RFC 6793). It isn't assigned to any network.
At a glance
- Block
- AS23456
- Defined in
- RFC 6793
- On the public internet
- No
About this block
AS numbers grew from 2 to 4 bytes in 2007. When a router with a 4-byte AS number talks to an old router that only understands 2-byte ones, it gives AS23456 in its place and carries the real number in a separate field.
Where you'll see it
- BGP sessions and AS paths involving very old routers.