Global Crossing Limited is a telecommunications company that provides computer networking services worldwide. It maintains a large backbone and offers transit and peering links, VPN, leased lines, audio and video conferencing, long distance telephone, managed services, dialup, colocation and VoIP, to customers ranging from individuals to large enterprises and to other carriers. The main emphases are on higher margin layered services like managed services and VoIP with leased lines. Global Crossing is a tier 1 carrier. - Source: Wikipedia