AS12684: the SES-LUX-AS network

AS12684 is an internet Autonomous System operated by SES-LUX-AS (Luxembourg). Here is what that means and why this number may show up when you investigate a connection on your network.

What is AS12684?

An Autonomous System (ASN) is a block of networks under a single control with its own routing policy on the internet. The number AS12684 was assigned to SES-LUX-AS by an RIR (regional internet registry). All traffic entering or leaving that network is announced under this number.

Reach on the internet

AS12684 currently announces 82 IPv4 block(s), totaling about 181 thousand addresses (180,992 in all), registered in Luxembourg. Services from SES-LUX-AS are reached through these addresses.

What it means to see AS12684 on your network

When you investigate where a connection from your computer or phone comes from (or goes to), you may find AS12684. That means the other end sits on the SES-LUX-AS network (Luxembourg). It can be legitimate — a cloud service, an ISP, a CDN — or an unexpected connection worth checking.

How to see every connection and network your devices reach

Tracing one connection's ASN at a time is tedious. Sentinela, by PC Monitor, maps the devices on your network, shows what is exposed to the internet and helps flag suspicious connections and devices — running on your Windows. Meet Sentinela.