AS9601: the SHIBATA Niigata Communication Service network

AS9601 is an internet Autonomous System operated by SHIBATA Niigata Communication Service (Japan). Here is what that means and why this number may show up when you investigate a connection on your network.

What is AS9601?

An Autonomous System (ASN) is a block of networks under a single control with its own routing policy on the internet. The number AS9601 was assigned to SHIBATA Niigata Communication Service by an RIR (regional internet registry). All traffic entering or leaving that network is announced under this number.

Reach on the internet

AS9601 currently announces 6 IPv4 block(s), totaling about 27.6 thousand addresses (27,648 in all), registered in Japan. Services from SHIBATA Niigata Communication Service are reached through these addresses.

What it means to see AS9601 on your network

When you investigate where a connection from your computer or phone comes from (or goes to), you may find AS9601. That means the other end sits on the SHIBATA Niigata Communication Service network (Japan). 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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