AS45557: the VNTT-AS-VN Vietnam Technology and Telecommunication JSC network

AS45557 is an internet Autonomous System operated by VNTT-AS-VN Vietnam Technology and Telecommunication JSC (Vietnam). Here is what that means and why this number may show up when you investigate a connection on your network.

What is AS45557?

An Autonomous System (ASN) is a block of networks under a single control with its own routing policy on the internet. The number AS45557 was assigned to VNTT-AS-VN Vietnam Technology and Telecommunication JSC by an RIR (regional internet registry). All traffic entering or leaving that network is announced under this number.

Reach on the internet

AS45557 currently announces 6 IPv4 block(s), totaling about 7.2 thousand addresses (7,168 in all), registered in Vietnam. Services from VNTT-AS-VN Vietnam Technology and Telecommunication JSC are reached through these addresses.

What it means to see AS45557 on your network

When you investigate where a connection from your computer or phone comes from (or goes to), you may find AS45557. That means the other end sits on the VNTT-AS-VN Vietnam Technology and Telecommunication JSC network (Vietnam). 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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