AS16481 BABSON-GNET

Nineteen announcements, one parent block, one netname, and a stray letter in the handle that nothing explains.

What it's used for

• A college's network. Nineteen IPv4 prefixes announced from the United States, no IPv6, sixty-five thousand five hundred and thirty-six addresses, through three observed BGP neighbours.

Notable

• All nineteen prefixes come out of a single parent range and together account for the whole of it. The college holds one block and announces it in nineteen pieces.
• The pieces come at seven different sizes and sit in no useful order relative to each other.
• Every registered block carries the same netname: the college and the word for a network.
• The AS handle uses a different word: the college, then the same network word with an extra letter in front of it. Nothing else in the record accounts for that letter.
• Eighteen addresses were queried for reverse DNS and none returned a name.

Interesting

• Splitting one block into nineteen announcements is usually traffic engineering that was never undone. Each piece was a decision about which upstream should carry which part of campus, and the pieces outlive the reasons.
• A letter in the handle that appears nowhere else is a fragment of some earlier arrangement: a consortium, a network name, a project. The registry keeps it because nothing forces anyone to explain it.
• One netname across nineteen registrations says the field was never meant to distinguish anything. The addresses do that work; the name only says whose they are.