AS16164 SOHONET-AS Sohonet Transit Network

Three countries, three company entities, three domains, and three different reverse naming schemes.

What it's used for

• A transit network. Three IPv4 prefixes and one IPv6 block announced from the United Kingdom, two thousand five hundred and sixty addresses, across ninety-seven observed BGP neighbours.

Notable

• All nine queried addresses answered. Each block uses a different convention: one prefixes the brand's short form to the four numbers in hyphens, one prefixes a three-letter country abbreviation, and the third runs that abbreviation straight into the last number and then gives the first three numbers.
• The three blocks answer on three different domains, one national, one generic and one for a third country, so the same company is publishing under three names at once.
• The registrants match: the same brand appears under three legal forms in three jurisdictions, and the third lists an incident response team object rather than a plain abuse role.
• One netname is address-derived, naming a range four times larger than the block announced from it.
• Another carries an extra word between the brand and the date that appears again in a contact name.

Interesting

• Ninety-seven peers for two and a half thousand addresses is the clearest signal in this record. The business is moving other people's traffic between facilities, and the address space is only there to number the equipment doing it.
• Naming schemes diverge by office, not by design. Each site named its own zone, and nobody ever had a reason to make them agree.