AS10750 MARK-TWAIN

MARK-TWAIN is Mark Twain Rural Telephone Co., an incumbent rural telephone company serving northeast Missouri — the Mark Twain country the name refers to. Like most rural telcos of its generation, it grew from switched voice into broadband and now runs a small eyeball network of its own.

What it's used for

This is residential and small-business internet access. RIS observes 17 announced IPv4 prefixes carrying 15,616 addresses, 1 IPv6 prefix (2605:2940::/32), and 7 observed neighbours — a handful of upstreams, no peering business.

The reverse DNS is a textbook subscriber network: nearly every sampled address resolves to an auto-generated PTR of the form 199.127.48.5.dsl.marktwain.net or 67.221.204.5.marktwain.net. Machine-generated PTRs that simply embed the address are what an operator produces when it has to name thousands of dynamically assigned customer lines and nobody is going to name them individually. The dsl label names the access technology on those particular pools, which for a rural incumbent means copper-delivered broadband to homes and farms; the un-labelled marktwain.net pools are the rest of the access and infrastructure space.

Two hosts break the pattern and are worth noting: mail.teammelvin.com, a customer's own domain parked on the operator's space, and huck.drac.marktwain.net — a DRAC is a Dell server's out-of-band management controller, so that is an internal server, named after Huckleberry Finn.

Notable

Around 15,600 addresses across 17 scattered prefixes, assembled from several different /8s, is the classic accretion pattern of a small telco that has picked up address space in small grants over decades rather than in one allocation.