Southern Crossroads (SoX) also known as Southern Light Rail (SLR) is a 501(c)3 organization that serves the Southeastern U.S. Research and Education community. SoX provides high-speed, global connectivity and other commodity services. SoX also serves as the Southeast connector to National Lambda Rail (NLR), Internet2 and other major U.S as well as International research networks.

Through its membership in The Quilt, SoX is able to offer low cost Internet bandwidth throughout the region with Internet Service Providers like Qwest, Sprint, and Cogent.

SoX supports universities, K-12 education networks, federal agencies, government laboratories and non-profit institutions that promote research in the Southeast region of the United States.

SoX services are enabled at 55 & 56 Marietta Street in Atlanta, Georgia. This presence provides SoX access to multiple peer groups already present at these carrier hotels.