SightCall announced Version 5.4 of its WebRTC real-time communication platform this week. The release marks a lot of hard work by the development team to bring some major new capabilities. The new features round out the platform beyond video and audio to include low latency messaging (data or text) and near-instantaneous status notifications.
Behind the scenes, SightCall implemented a new low-latency all in-memory pub/sub service between our datacenters. For status notifications, each user may set their status level to an integer between one and 255. Users may also register a list of other users whose status level they are interested in knowing about. This list is called the ‘roster.’ If the status level of a user in your roster, you will receive an instantaneous notification of the new status level.
The status level and roster can be used to implement different capabilities. In its most typical use, a status level corresponds to a Presence setting. In an instant-messaging application like Facebook Messenger or Skype these have names like ‘online’, ‘away’, ‘do-not-disturb’, ‘getting coffee’, etc. When used this way, a change in your “Presence” will be seen by your friends instanteneously.
The status level may also be used to signal “Typing” activity. In applications like Apple iPhone ‘Messages’, when a contact is typing you may see an elipsis (“…”) to show that they are composing a message. This little bit of information can be enough to keep your contact engaged while you are writing a message. It’s a nice feature. Using the SightCall platform, one bit of the status level can be devoted to a typing indicator.
Text Chat is another new feature implemented on the same low-latency pub/sub service that implements the status level and roster. Where the status notification service implements a one-to-many pattern, Text Chat is implemented as a one-to-one data message between two users.
The inclusion of the status level and text chat features was a request that we often received from our users. We listened. By including these in the platform, SightCall handles video call set up, text chat, and presence in one unified API. That means a single WebSocket (wss:) from your web browser or mobile device is used to multiplex signaling, messaging and notification services.
SightCall has released an open source Web Application that illustrates all of these features. It is called “SightCall Communicator” and resides at
You can try it out by hosting it on Heroku in just a matter of minutes. Make one-to-one calls, use Text chat, set up a Conference call and possibly record it to the Cloud. Try it out and let us know what you think.
Chat and Presence Tutorials