MCLEAN, Va.--(BUSINESS WIRE)--GTT Communications, Inc. (NYSE: GTT) and AT&T (NYSE: T), have signed a long-term, bilateral agreement for their IP networks. As the Internet continues to evolve, collaborations between Internet providers facilitate the dynamic, robust and reliable exchange of Internet traffic. “We are pleased that our agreement with AT&T provides our clients with additional capacity,” said Rick Calder, GTT President and CEO. “We continue to work with AT&T to expand a se