Google Voice is an excellent service with outstanding potential however the lack of SIP support is preventing wide-spread adoption among existing VOIP users. We, the undersigned, respectfully request that Google Voice provide full support for the SIP protocol so we can easily integrate/connect vendor-neutral VOIP gateways, phones, and software.
We acknowledge that there were legitimate security concerns that originally prompted Google to block SIP support. A possible solution would be for Google to allow SIP access based on an account-specific IP or SIP URI access list. Thus, SIP calls to and from explicitly authorized IP addresses would be allowed; all other calls would be blocked. Other security options can/should be explored as well.
Offering SIP support would provide several immediate benefits for both Google and customers including (but not limited to):

• Promotion of the SIP open source standard.
  
• Immediate appeal to additional market segments (including personal tech-savvy users and businesses leveraging existing SIP technology).
  
• Improved competition with other VOIP services (e.g. Skype, Vonage, etc). 

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