AS18378: the NIWA-AS-AP National Institute of Water and Atmospheric Research Ltd network

AS18378 is an internet Autonomous System operated by NIWA-AS-AP National Institute of Water and Atmospheric Research Ltd (New Zealand). Here is what that means and why this number may show up when you investigate a connection on your network.

What is AS18378?

An Autonomous System (ASN) is a block of networks under a single control with its own routing policy on the internet. The number AS18378 was assigned to NIWA-AS-AP National Institute of Water and Atmospheric Research Ltd by an RIR (regional internet registry). All traffic entering or leaving that network is announced under this number.

Reach on the internet

AS18378 currently announces 2 IPv4 block(s), totaling 512 addresses (512 in all), registered in New Zealand. Services from NIWA-AS-AP National Institute of Water and Atmospheric Research Ltd are reached through these addresses.

What it means to see AS18378 on your network

When you investigate where a connection from your computer or phone comes from (or goes to), you may find AS18378. That means the other end sits on the NIWA-AS-AP National Institute of Water and Atmospheric Research Ltd network (New Zealand). 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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