AS55566: the IUCAA-IN Inter University Centre for Astronomy and Astrophysics network

AS55566 is an internet Autonomous System operated by IUCAA-IN Inter University Centre for Astronomy and Astrophysics (India). Here is what that means and why this number may show up when you investigate a connection on your network.

What is AS55566?

An Autonomous System (ASN) is a block of networks under a single control with its own routing policy on the internet. The number AS55566 was assigned to IUCAA-IN Inter University Centre for Astronomy and Astrophysics by an RIR (regional internet registry). All traffic entering or leaving that network is announced under this number.

Reach on the internet

AS55566 currently announces 2 IPv4 block(s), totaling 768 addresses (768 in all), registered in India. Services from IUCAA-IN Inter University Centre for Astronomy and Astrophysics are reached through these addresses.

What it means to see AS55566 on your network

When you investigate where a connection from your computer or phone comes from (or goes to), you may find AS55566. That means the other end sits on the IUCAA-IN Inter University Centre for Astronomy and Astrophysics network (India). 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

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