AS16399 FIRSTCOMM-AS2

The netnames are numbered two, four, six, seven, eight and nine, and the number two is used three times.

What it's used for

• A provider's network. Thirty-six prefixes announced from the United States, three of them IPv6, one hundred and twenty-seven thousand two hundred and thirty-two addresses, through seven observed BGP neighbours.

Notable

• Most netnames are the company's short name, the word for a network, and a numeral. The numerals skip values, and the lowest one appears on three separate blocks.
• Four more blocks carry a five-letter name from an acquired provider, with no numeral and no date.
• The numbered blocks list three contacts each: the company, a systems administration team, and an abuse contact under the company's initials. The acquired blocks list the company alone.
• Nine of eighteen queried addresses answered, across four domains in three styles. Some write the address hyphenated with a label naming the protocol version. Some write it hyphenated with the word for a static assignment. Two write it backwards, one with a label for a business line and one for a leased line.
• One answer is a customer's own domain with a single number after the word for a host.

Interesting

• Numbering your networks only works if you keep the list. Gaps and repeats mean the numbering outlived whoever was tracking it, which is what happens when a provider grows by acquisition.
• Four reverse-name conventions on one network is four acquisitions' worth of DNS that was never consolidated. Each one still resolves, which is the only test that ever mattered.