AS15121 — CALTEL-COM

AS15121 announces 2 IPv4 prefixes covering 5,120 addresses and 1 IPv6 prefixes.

About this network

A single letter in front of the address so the label does not start with a digit.

What it's used for

• A rural internet provider. Two IPv4 prefixes and one IPv6 /32 announced from the United States, with two observed BGP neighbours.

Notable

• Both sampled addresses answered, in the form dsl-254.a66-102-155.caltel.us: the service type and final octet as one label, then the first three octets prefixed with a lone a.
• The same shape appears across both blocks, so one convention covers space from two unrelated ranges.
• Both blocks carry the netname CALTEL-NETWORK and are registered to the holder.
• The AS handle and the netname both use a contraction ending in TEL while the registered company name says internet, so the abbreviation records what the business was before.

Interesting

• The stray letter is a workaround for a rule that host name labels should not begin with a digit. Several holders in this corpus solve it the same way, each picking a different letter, and none of them documents the choice anywhere. It is invisible until something tries to parse the address back out of the name and has to know to strip one character.
• Splitting the name into a host part and a network part, rather than flattening the whole address into one label, keeps the structure readable and makes the service type the first thing anyone sees.
• A /32 of IPv6 against five thousand IPv4 addresses is the standard rural provider allocation.

This description is AI-generated, best-effort context — not authoritative, and provided without any guarantee of accuracy.

Announced prefixes

• 66.102.144.0/20
• 198.105.28.0/22
• 2604:a780::/32

Upstream networks

• AS174 Cogent Communications, LLC
• AS54048 Vast Networks

Adjacent networks

• AS174 Cogent Communications, LLC
• AS54048 Vast Networks