A A SBC joins VoIP 911 Om Malik May. 11, 2005 - 5:05 PM PDT May. 11, 2005 - 5:05 PM PDT SBC, the last holdout has decided that it is going to open its 911 infrastructure to VoIP providers. Verizon, BellSouth and Qwest are pretty much on board. Andy worries about 911 and its impact on Vonage.