Xelas Software has been providing OSI protocol software since 1985. As as successor to Retix and Vertel Corporation this software has been the cornerstone of network management, mediation and integration solutions to both telecom infrastructure vendors and service providers such as Alcatel-Lucent, Nokia, Siemens, Motorola, Nortel, Huawei, China Telecom, China Mobile, NTT, Samsung, AT&T, British Telecom (BT), Deutsche Telecom, T-Com, Verizon, Williams Communications, Level 3 Communications and many more.