AS16220 UTCBNET

Reverse names written by hand, labelling broadcast addresses, campuses and the border router by name.

What it's used for

• A university's campus network. Four IPv4 prefixes announced from Romania, no IPv6, three thousand eight hundred and forty addresses, through one observed BGP neighbour.

Notable

• None of the four blocks is registered to the university. Two belong to the national informatics research institute, one to the national education network agency, and one lists only an abuse role.
• Three netnames carry a date. Two write it as eight digits, the oldest as six, dropping the century.
• Ten of twelve queried addresses answered, and every name was typed by somebody rather than generated.
• Four begin with an abbreviation for broadcast, so the last address of a range is labelled as such instead of being left to the reader to work out.
• Others name a campus, a city district, the administration network, a departmental address pool, and the border router, which is called exactly that.

Interesting

• Hand-written reverse names scale badly and survive anyway, because the person maintaining them knows what every range is for. A campus is small enough that this is still true after decades.
• Marking broadcast addresses in DNS is a courtesy to whoever is reading a packet capture at three in the morning. It costs one record per range and answers a question before it is asked.
• The university runs the network but holds none of the addresses. The research institute is the member of the registry, and the campus is a customer of it.