104
Doing Gigabit Ethernet Over My British Phone Wires – The HFT Guy
(thehftguy.com)
This is a most excellent place for technology news and articles.
Iirc you should check for ~~continuity~~ current depending on where you live. There could be a minimal amount of power still going through those lines. This could be very outdated info as well since i haven't done residential contacting in a long time.