AS26599: the TELEFONICA BRASIL S.A network

AS26599 is an internet Autonomous System operated by TELEFONICA BRASIL S.A (Brazil). Here is what that means and why this number may show up when you investigate a connection on your network.

What is AS26599?

An Autonomous System (ASN) is a block of networks under a single control with its own routing policy on the internet. The number AS26599 was assigned to TELEFONICA BRASIL S.A by an RIR (regional internet registry). All traffic entering or leaving that network is announced under this number.

Reach on the internet

AS26599 currently announces 170 IPv4 block(s), totaling about 10.8 million addresses (10,785,280 in all), registered in Brazil. Services from TELEFONICA BRASIL S.A are reached through these addresses.

What it means to see AS26599 on your network

When you investigate where a connection from your computer or phone comes from (or goes to), you may find AS26599. That means the other end sits on the TELEFONICA BRASIL S.A network (Brazil). 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.