AS1653: the SUNET SUNET Swedish University Network network

AS1653 is an internet Autonomous System operated by SUNET SUNET Swedish University Network (EU). Here is what that means and why this number may show up when you investigate a connection on your network.

What is AS1653?

An Autonomous System (ASN) is a block of networks under a single control with its own routing policy on the internet. The number AS1653 was assigned to SUNET SUNET Swedish University Network by an RIR (regional internet registry). All traffic entering or leaving that network is announced under this number.

Reach on the internet

AS1653 currently announces 70 IPv4 block(s), totaling about 489.5 thousand addresses (489,471 in all), registered in EU. Services from SUNET SUNET Swedish University Network are reached through these addresses.

What it means to see AS1653 on your network

When you investigate where a connection from your computer or phone comes from (or goes to), you may find AS1653. That means the other end sits on the SUNET SUNET Swedish University Network network (EU). 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.