tag:blogger.com,1999:blog-1923078024539080324.post6708442891762876755..comments2008-06-06T09:41:59.459+01:00Pete Jenkinsnoreply@blogger.comBlogger2125tag:blogger.com,1999:blog-1923078024539080324.post-62365835633467866622008-06-05T23:58:00.000+01:002008-06-05T23:58:00.000+01:00Pete: We use a 3300v with two Zyxell ADSL modems on the back, externally we have an Asterisk box hosted in the US and, all our team have Snoms on their desks. One line is with Bulldog, the other BT.<BR/><BR/>We have the system setup to prioritise on destination IP, so all comms to our US server is given priority, both lines are load balanced with the 3300 knowing what the bandwidth (listed) is for each channel.<BR/><BR/>It works, but I wouldn't sell it !<BR/><BR/>The Snoms also support failover registration, which I've setup to test, but found no benefit.<BR/><BR/>Now the down side, call quality in the main is good, however if one of the lines is playing up, call quality will reduce, with ocassional drops.<BR/><BR/>My biggest problem is the re-registration, if one of the lines goes down and back up, the phone will loose it's connection, and in the main doesn't recover until a handset restart. This is a real pain ! Even with the failover setup, the phone doesn't appear to realise it needs to re register, I guess it sees itself as reconnected and if it can see the server, it's happy.<BR/><BR/>The Snom Distributor we work with doesn't recommend load balancing in any form with VoIP, they would recommend a dedicated line for VoIP and a second line for data, I'm reluctant to do this and have been plodding on with the load balanced solution.<BR/><BR/>The Siemens Dect IP phone we have hates the load balanced setup, loosing it's connection at least once a day, yet the same unit I have at home on a single DSL line works a dream !<BR/><BR/>We have found some improvements with keeping the 3300's firmware up to date, but if anybody finds a better router which resolves these issues, let me know.Joelhttp://www.blogger.com/profile/05896008722605630448noreply@blogger.comtag:blogger.com,1999:blog-1923078024539080324.post-13335617585793944462008-04-17T08:50:00.000+01:002008-04-17T08:50:00.000+01:00Update: After speaking to a few people with experience of load balancing routers and failover routers. There may be one or two more things to keep in mind.<BR/><BR/>It is possible that VoIP over a bonded line may cause problems with the NAT (Network Address Translation) as voice data packets will originate from any of the 2 or more IP addresses in use.<BR/><BR/>With failover between 2 broadband connections, it may be necessary to reboot any VoIP devices that have registered with a VoIP service over the failed connection in order to re-establish their registrations.<BR/><BR/>I'm not sure whether this part can be handled automatically yet. Whether behind NAT or non-NAT the IP address used by the VoIP devices changes when the ADSL line switches, which means that any cached registrations will be out of date. The VoIP devices don't know about the ADSL line switching so don't know that they have to re-establish the registration. This is not so much an issue with NAT as they register ever 30 seconds, however VoIP devices do cache a route internally and may still need to be restarted to clear this down.Pete Jenkinshttp://www.blogger.com/profile/05041618736839549007noreply@blogger.com