As a true hosted SIP provider, we offer the entire spectrum of SIP services
SIP Addresses and SIP Hosting
Each of our end users gets a SIP address of their choosing. In fact, even features like voice mailboxes and On Net Conference Suites get their own unique SIP address. Through a free feature we call SIP domain hosting, users can set their SIP address to match any preferred email address of their choosing. Anyone can call you by punching in your SIP address into his or her phone, instead of dialing a meaningless series of random numbers.
Making calls to and from SIP addresses is absolutely free. SIP to SIP calls that do not dip into the PSTN at any point use the Internet for sending the media streams, meaning that users are already paying for them when they pay their Internet bills. OnSIP incurs the cost of handling the signaling process, but that number is negligible.
OnSIP will also automatically recognize SIP address aliases so if a user is dialing a number that actually corresponds to a SIP address, that call will also be free. Finally, all extension-to-extension calls within an OnSIP hosted PBX are free as well.
Wide Compatibility Range
As a service that is entirely based on SIP, we can take advantage of how versatile and flexible the technology is. This is the reason why users can bring any SIP phone to our service. This is the reason why our users have been getting HD voice on their HD capable SIP phones since the hardware was released. This is also the reason why we can say that we support additional media types such as video, and more.
We let the different user agents in a call negotiate amongst themselves to decide what type of communication session will be held.