AS16430 USM - University of Southern Mississippi

Three letters serve as the handle, the netname, and the whole of the university's shorthand.

What it's used for

• A university's network. One IPv4 prefix announced from the United States, no IPv6, sixty-five thousand five hundred and thirty-six addresses, through two observed BGP neighbours.

Notable

• The AS handle is three letters and nothing else: no hyphen, no suffix, no numeral. It is the shortest handle in this range.
• The netname is the same three letters, and the registrant is the university's full name. Every field agrees, which is unusual enough here to be worth saying.
• The entire announcement is one block, at the largest prefix size in common use, held under a single registration.
• Three addresses were queried for reverse DNS and none returned a name.
• Two observed neighbours carry all sixty-five thousand addresses.

Interesting

• Universities were allocated address space by the block long before anyone counted hosts, and a single unbroken allocation of this size is a receipt for arriving early. Nothing about the campus requires this many addresses; the allocation records when the request was made.
• A three-letter identifier only works while nobody else wants it. It survives here because the registration is old enough to predate the competition for short names, and because nobody has had reason to touch the record since.
• Silence in reverse DNS across a block this large means the campus resolves its own names inward and publishes nothing outward. The addresses are for people, not for services other networks need to find.