In my previous feature highlight posts they have often contained screenshots, details of the options, and given a sample a use case or two to help explain what could be accomplished with the features. The two that I’ll talk about today are mostly unseen in terms of the admin screens and really only come into play as a phone rings. So they are not as obvious as the past ones seen as options on the admin screens but could be just as useful depending on your use case.
The first a SIP phone’s BLF (busy lamp field). Typically with asterisk a BLF will indicate if a phone is busy, ringing, and if pressed will dial that extension. This is done by putting the extension to monitor as the BLF value associated with one of the line appearances or buttons on the SIP phone depending on the brand and how it’s BLF are assigned to user visible buttons/lights.
The Q-Suite offers more options by adding different prefixes to the BLF value. The first makes the BLF button work more like a SLA (shared line appearance) although not 100% but for those coming from the analog world they often need it to transition to how the VoIP world works. In the analog world it’s easy to have a copper pair to each phone and connect them all back at the demarc so each phone can have that individual line and show when in use by others. To get something similar where you can monitor the line and also answer if it’s ringing the BLF value can be set to slaX where X is the extension to monitor and sla gives the abilities to answer that extension if it’s ringing. If that line is not busy then pressing the button will result in dialing the extension. The second is an extension of this and it requires the extension being monitored to be associated with a specific trunk, so the monitoring will indicate if the phone or specific trunk is busy. This is configured by having slatrkX as the BLF value but is only really useful in limited situations where the outside line is a single analog port.
Using the above is typically reserved for those converting from analog who do not want to change their mindset. Usually a combination of BLF, forwarding, and using a Ring Groups can accomplish the purpose behind the traditional SLA lines. So lets look at a couple cases:
- The most common case is ringing multiple extensions and having any one person answer the call. The VoIP solution is straightforward as putting all the extensions in a ring group and having a DID or Auto-Attendant option direct the call to that ring group.
- Another case is a small office of 3-4 people each with their own line, and this is where the light would indicate if they are busy or not. Showing it ringing would also be helpful if that person is out for the day and one of the others needs to answer those calls. The VoIP solution requires a couple changes here, the first would be for the person being out to forward their phone to another extension if all calls are meant to be answered. Each person would also have a BLF setup to monitor the others in the office, likely with slaX or just the extension number. Adding slaX would allow them to answer the call also, but I’d recommend forwarding to avoid missing any calls. With forwarding the other phone will ring and also log any missed unanswered calls.