Home Box to Trixbox

Next, I needed to define internal extensions for the Kitchen, Schoolroom and Office.

After selecting Extensions from the left-side menu, I chose to Add a ZAP extension. I gave extension number 22, display name Office and channel 2 to my office phone. Giving it channel 2 means it is plugged in to socket 2 on the Digium PCI card.

I then enabled voice mail on that channel and assigned the required voice-mail password. After selecting Submit, the new channel appears in the right-side menu. When it is selected again from the menu, the Device Options have more parameters that could be modified, but the defaults are sufficient (Figures 10 and 11). Extension 24, assigned to the Kitchen phone on channel 1, is configured similarly (Figures 12 and 13), and the voice mail on this extension is the family voice-mail box. The Schoolroom, assigned extension 23 and channel 3, is also similar but voice mail is left disabled (Figure 14). That completes all three of the real extensions on the system.

Figure 10. Default device options are sufficient for ZAP extension 22.

Figure 11. More Default Device Options

Figure 12. Similar Configuration for Kitchen Extension 24

Figure 13. More Default Device Options for Extension 24

Figure 14. The Schoolroom extension 23 leaves voice mail disabled.

I also designed one pseudo-extension that will ring the whole house and another to ring only the Kitchen and Schoolroom phones. I used Ring Groups for this. A Ring Group is a set of extensions that are associated with each other, can be dialed with a single number and can ring in a specific order. Selecting Ring Groups from the left-side menu, I defined group number 20 for the whole house. I put all three real extensions into the extension list and set them to all ring at once, which is the strategy ringall (Figure 15).

Figure 15. The ring group 20 will ring the whole house.

I set the ring time to 20, the same timeout as the other extensions, and if no one answers, the call will go to the family voice-mail box (24). Making a ring group for the house extensions is exactly the same, but only extensions 23 and 24 are in the list (Figure 16). These ring groups can be dialed from any internal extension or from an incoming call that is allowed to dial extensions directly. One nice thing about using these ring groups is that during the school year, I can drop the extension in the Schoolroom from the ring group, so people in that room are not disturbed during the day. In the summer, I can add that extension back into the group.

Figure 16. Ringing the Whole House from an Extension

The system has three devices for receiving and placing calls, and they can be accessed by five extension numbers.

Although calling between extensions is certainly cool and useful, calling out of the system is still required. Outbound Routes is where that gap is bridged. For ease of configuration and for faster parsing of dialed numbers, I configured the system so that all numbers dialed out through the phone company will be prefixed with the digit 9. Selecting Outbound Routes from the left-side menu, I defined a route called 9_outside (Figure 17) for passing outgoing numbers to the PSTN trunk, which is ZAP/g0.

Figure 17. Handling 9 for Outside Lines and 911 Separately

ZAP/g0 is a group containing all the ZAP channels that connect to the phone company, which is defined by default at installation by Trixbox. These groups are similar to the phone system concept of a hunt group: the channels are tried in sequence and the first one that is available will be used.

The dial patterns that I direct to this trunk are 911 and 9|.. The former pattern indicates that when 911 is dialed by an extension, the system dials 911 on the chosen trunk. The latter pattern (9|.) matches any dialed number that begins with a 9, followed by any number of digits.

The system then strips off the 9, as indicated by the vertical bar (|), and sends the remainder of the digits to the trunk. I handle 911 separately from other 9-prefixed numbers, because I do not want anyone to have to know or remember to prefix 911 with a 9 to get out (9911). Because there is only one trunk for dialing out and outgoing numbers must be prefixed with a 9, the outbound routes were very easy to define.