Cisco, Juniper(now HP), Huawei, Nokia, NTT, Hurricane Electric

Pretty much anyone who wants to sell you internet capable hardware ( like chassis routers or mobile base stations) or people wanting to sell you internet services.

Edit: forgot security companies to scare you into buying the latest SASE, SIEM, unified security product.

Cloudflare routes 20% of the world’s internet traffic. That’s a very large sample. They publish an annual radar report. https://radar.cloudflare.com/year-in-review/2025

Marketing companies

Companies that sell and host applications.

Online gaming companies.

Streaming media companies

Awareness of consumer behavior is of huge value to pretty much all companies.

There are tons of communities for questions, this isn't one