I moved away from Netgear products in all of my VoIP installations due to issues running SIP traffic through them - I'd get random call drops, jitter, etc. I was able to solve some of it by reducing the MTU on the network device (my going theory behind that was it was buffering less so it had a better transmit/receive rate but I never was able to figure out why that worked) but I never really got it totally handled until I switched vendors.
What kind of hardphones are they using? Some brands will handle jitter or lost packets far more smoothly than others. I've had the best luck with Polycom phones but you might not always have a choice with hosted VoIP. Also, just like some of the other replies have said - check your traffic usage. You can easily cripple a VoIP call running across a pretty fast connection with obvious things like bittorrent, but even less obvious things like running a RDP session across the connection will introduce a stunning amount of quality loss. ---- Jack Kramer Computer Systems Specialist University Relations, Michigan State University w: 517-884-1231 / c: 248-635-4955 On 2/23/11 8:07 AM, "Steve Hanna" <sha...@fleet.ca> wrote: > >Sorry for the off topic post but this is the most knowledgeable group of >folks I know. I am trying to sort out some issues with an IP phone >installation, the scenario is as follows: 6 IP phones that speak to a >hosted >VOIP service (versature.com) this was running over a normal DSL connection >and it was discovered that the DSL had a very low sync rate and a very >high >latency (bad for IP phones) so they contracted to have a T1 installed >*but* >the call quality still has issues (breaking up). I am trying to think of >what could be causing the issue. > >the latency is minimal <30ms >the bandwidth is more than enough now (T1 reports 1.47mbs up and 1.46 >down) >the switch is 10/100/1000 >the firewall is also 10/100/1000 on the LAN side (NETgear SRXN3205) >Wan side is a Cisco 1841 (Bell Canada Owned, I have no access to) > >This is not @ my dayjob it is however @ my wife's dayjob (so my B@lls are >in >it to try and help) > >Just wondering if anyone has any ideas where to look, > >cheers >--Steve > > > >~ Finally, powerful endpoint security that ISN'T a resource hog! ~ >~ <http://www.sunbeltsoftware.com/Business/VIPRE-Enterprise/> ~ > >--- >To manage subscriptions click here: >http://lyris.sunbelt-software.com/read/my_forums/ >or send an email to listmana...@lyris.sunbeltsoftware.com >with the body: unsubscribe ntsysadmin ~ Finally, powerful endpoint security that ISN'T a resource hog! ~ ~ <http://www.sunbeltsoftware.com/Business/VIPRE-Enterprise/> ~ --- To manage subscriptions click here: http://lyris.sunbelt-software.com/read/my_forums/ or send an email to listmana...@lyris.sunbeltsoftware.com with the body: unsubscribe ntsysadmin
