AS3603: the University de Los Andes network

AS3603 is an internet Autonomous System operated by University de Los Andes (Colombia). Here is what that means and why this number may show up when you investigate a connection on your network.

What is AS3603?

An Autonomous System (ASN) is a block of networks under a single control with its own routing policy on the internet. The number AS3603 was assigned to University de Los Andes by an RIR (regional internet registry). All traffic entering or leaving that network is announced under this number.

Reach on the internet

AS3603 currently announces 2 IPv4 block(s), totaling about 65.5 thousand addresses (65,536 in all), registered in Colombia. Services from University de Los Andes are reached through these addresses.

What it means to see AS3603 on your network

When you investigate where a connection from your computer or phone comes from (or goes to), you may find AS3603. That means the other end sits on the University de Los Andes network (Colombia). 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.