AS8251 NFX_ZSPO

NFX_ZSPO is NFX, z.s.p.o. — a Czech zájmové sdružení právnických osob, an association of legal entities — operated together with FreeTel, s.r.o. It exists to give the country's community "free net" networks shared upstream transit and peering at NIX.CZ in Prague.

What it's used for

• Around 17,400 addresses in six prefixes, plus IPv6, and transit for roughly sixteen downstream member ASNs.
• The reverse DNS is the giveaway: the space is filled with the member community networks' subscriber routers — router.NAME.klfree.cz (KLFree, Kladno), NAME.pilsfree.net and dhcp.pilsfree.net (PilsFree, Plzeň), 78-108-100-NN.czela.net (CZELA.net, Čelákovice), and NN.nat.hutisko.hvfree.net.
• Names like rodova-vila-nat.pilsfree.net and per-member router hostnames are exactly what a member-run residential network looks like: households and small NAT gateways, not datacentre or corporate assignments.

Notable

• The addresses land in homes, even though the AS holder is an association rather than a retail ISP. Czech community networks are member-owned cooperatives, and the AS is their shared route to the internet.
• A handful of infrastructure and service hosts share the space (speed.nfx.cz, an IPTV provider), so it is not exclusively subscriber addressing.