AS15305 SYRINGANETWORKS

Sixty-six neighbours, customer telephone companies numbered in the netnames, and one reverse name pointing at the wrong address.

What it's used for

• A regional carrier. Forty-one IPv4 prefixes and two IPv6 prefixes announced from the United States, thirty-three thousand addresses in total, across sixty-six observed neighbours.

Notable

• One sampled reverse name encodes an address in a completely different block from the one that answered, so the record and the address disagree.
• Customer blocks are registered to rural telephone companies under netnames built from a three letter prefix, a five digit zero padded customer number such as 00328 or 00238, and the address.
• The carrier's own netnames come in three forms: the full company name, the same with the address appended, and SYRI, four letters.
• Most registrant fields list the company plus a hostmaster, a network operations centre and an abuse desk, the most complete contact set in this range.
• A second domain appears in reverse DNS for the wireless side of the business.

Interesting

• The mismatched reverse name is the kind of error that survives for years. It resolves, it looks plausible, and anyone reading logs will place that address in the wrong part of the network.
• Numbering customers in the netname turns the registry into a billing index. It is efficient and it quietly publishes how many customers came before this one.
• Sixty-six neighbours on thirty-three thousand addresses is a carrier whose business is reaching places other networks do not, rather than carrying volume.