I currently have 4 lines coming into the house. We currently have an Avaya standard analog key system which has served us well, but running extensions is a major pain and requires a dedicated run per extension. I have ethernet run throughout the house though. The first two lines are "home" lines, however line1 I use for my consulting during the day, and line2 is used by my wife for her work during the day. Line3 is a separate business that nobody else in the household should be picking up, however I would like to be able to pick it up from any extension if required. Line4 is a fax, but is used for outgoing calls (like conference calls, etc.) so that the inbound lines can be left free. With the current system, I can choose which outbound trunk is used by just selecting the line button I prefer. My wife just picks up the phone for an outgoing call and it will choose line2, and if busy then line1. She would never use line3 or line4. The kids should never touch lines 3 and 4 either. They all know enough to only answer lines 1 and 2 and ignore lines 3 and 4, and can tell since each line has a different ring as well as the line lights that blink. We also regularly need to be able to "barge" in on each other's calls converting a regular call into a conference. I know what I'm looking for is SLA (Shared Line Appearance), and I've been trying to get that working for a couple of weeks. It supposedly works somewhat, but I cannot find enough coherent documentation as to exactly how to set up each of the extensions and the physical Polycom phones. I do see there's still bugs being worked on (even today) thats being tested: https://issues.asterisk.org/view.php?id=11688 So there's two questions here. First, is there a way to accomplish the requirements I have above to a generic asterisk installation, or are we talking a very large and complicated configuration? Second, is there anywhere I can find some detailed documentation on configuring SLA on Polycom phones? (For example, for each line on the Polycom phone, does it log in with an extension number or specifically the string "station1_line1", and does the sip.conf get a numbered extension for each line on the phone, or do you specifically put [statsion1_line1] in there?) Thanks in advance...