IRLP requires special hardware/software at both ends of the LINK -- that is, at the repeaters that are IRLP nodes.
Individual users can access the IRLP "network" through any IRLP-linked repeater the same way they would for a local QSO.
The only "special" equipment required is a radio with a DTMF (Touch-Tone) pad so that you can "dial up" the remote IRLP node (far away repeater) to which you want to connect.
All access is via "radio" -- that is, over the air through a linked repeater.
No access via computer.
And, unlike EchoLink, there's no registration required for individual users.
Read up on IRLP here:http://www.irlp.net/
Mel - KS2G