After a month of playing around with the Primus service, it’s finally starting to settle into a stable and reliable home-phone system.  My major problems in the first few weeks were (in no particular order):

  • (solved) Calls couldn’t be made after leaving the router up for a few hours.  All calls would result in a busy signal until the router was rebooted.  The problem with this was likely that the RTP connections were established by the first phone call and left up behind the firewall.  This problem was solved with a new WRT54GS router (see below).
  • (solved) Making calls while Bittorrent or other P2P apps were running would result in crackling on the other side of the phone call.  This was fixed by properly setting up QoS on the WRT54GS.
  • (solved) Phone calls were plagued every ten seconds or so by load popping noise on our side.  This happened whether it was plugged directly into the cable modem or behind a router.  From what I glean from Primus’ tech support and forums was that it was a bad interaction between their service and Shaw’s routers.  It seems to be working fine now.

All in all, the service is pretty good now.  I finished off my QoS tweaks this morning to get rid of any problems while we’re on the phone.  So far there don’t seem to be any excessive delay, crackling or echoing problems.

The biggest solution to the problem was changing out my old Linksys BEFSR81 router for a brand new WRT54GS.  I also took a leap and tried installing the upgraded Sveasoft firmware on it so I could take advantage of SSH and other utilities.

The BEFSR81 had a problem in gateway mode where it would drop stagnant connections from behind the gateway after a while.  This seems to be fixed in the WRT54GS (both stock and Sveasoft firmware versions).  In fact, I didn’t have to forward any ports whatsoever to get it working.  Very cool!

The other problem with the BEFSR81 was that it supported QoS, but not very well.  No matter what settings I tried, it wouldn’t give enough priority to the VoIP packets to survive while Bittorrent was running.  I had to set the upload/download maximums on the QoS page of the WRT54GS before I could get this to work reliably.  From what I’ve heard, a cable modem may queue up outgoing packets if you’re close to your maximum outbound rate.  This is pretty terrible for VoIP since packets need to reach the other side 100-150ms later to get a good quality call.

In the last couple of weeks, Primus has also been supporting the VMWI light on my Nortel Vista 350 properly.  The light comes on when we have voicemail and turns off once you’ve listened to it.  They seem to have preliminary support for emailing voicemail messages as .wav files, but it doesn’t seem to be working reliably.  It’s pretty nice to have an attachment in your mailbox to listen to whereever you are.  Saves having to remember the external voicemail access numbers as well.

I highly recommend picking up a WRT54GS or two and making these things part of your network.  It’s such a powerful little wireless router/gateway that it would be worth it at twice the cost.

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