Global crossing is a portal company. They exist as a portal for others (scammers) to do business through them. "Companies" overseas contract with them and they essentially provide a hub to "do business" with you. By "do business", I mean scam. Anyone in India (main culprit) can contract them, set up a hole in the wall in some alley and have calls from the USA routed to them. GC provide dialer services, meaning they sell them your phone number, dial it for them and connect them to you. This is typically done with local numbers to give this scamming a legitimate feel. They provide them point of sale services, through which they can bill your credit card. Then they keep a fee or a percentage of what the scammers bring in.
If you receive a call from this number (6023579425), you will surely be speaking to someone from India, attempting to convince you that you are being sued by the IRS and that you need to pay up. When you web search the number, you will come up with Global Crossing Local Services.
This is backed up by searching the BBB database and web searches on their business practices.
Technically, Global Crossing is a legitimate business. In reality, they exist to give the keys to your house to the thieves.