I heard that it is illegal to put IRLP linking onto a repeater on 2 meters in the USA. I was wondering if this was actually the case.
Is It Legal?
By Brennan Price, N4QX and ARRL General Counsel Chris Imlay, W3KD
What Part 97 regulations govern VoIP-assisted Amateur Radio?
All of them or none of them, depending on whether you're asking about the "VoIP-assisted" or the "Amateur Radio" part of VoIP-assisted Amateur Radio. Follow this link for a PowerPoint presentation on VoIP by Mike Goldberg, K1LJN.
Many callers to the ARRL's Regulatory Information Branch over the last few years have focused on the novelty of the Internet when asking questions about the legal uses of certain systems. Such focus is misdirected. Part 97 does not regulate systems; it regulates stations. The Commission doesn't care what a ham has feeding his or her station; it cares that the station--not the Internet, but the station--is properly operated. And all the rules that apply to any Amateur Radio station apply to one that retransmits audio fed to it by VoIP.
The gist of it is this: it's not illegal. All the FCC cares about is your station, and what you transmit. If your transmissions come from the internet instead of a microphone, more power to you. Just be sure those transmissions comply with the regulations like everything else.
It does not matter if the protocol you use on the internet is encrypted or not. Part 97 regulates the RF emissions from your station, not what you do on the internet.