I need to have my T1 Demarc extended and noticed you offer that service with something call ISTP, what is it?
ISTP stands for Individually Shielded Twisted Pair, it is a special type of cable in which each pair is shielded which helps reduce Near-end Cross Talk problems. While in some situations you may be able to use Category Cable (ex CAT5) to extend your demarc we recommend that T1 Demarcs only be extended with ISTP to reduce the odds of having future issues.