- Fujitsu Ltd
- Cisco Systems Inc.?
- IBM Corporation?
- AT&T Inc.?
- HP Development Company LP
- Microsoft Corporation?
- Verizon Communications Inc.?
- Dell Technologies Inc.?
- Nokia Solutions and Networks?
- Deutsche Telekom AG?
- Tata Consultancy Services Limited?
- Citrix Systems Inc.?
- Wipro Ltd
- NSC Global Ltd
- Telefonica Europe PLC