We run into it all the time when using the Comcast-provided "business class" equipment and a non-Comcast SIP provider. When we had a fiber hand-off from Comcast (about 3 years ago) and used a non-Comcast SIP provider we had no issues.
-A On Wed, Sep 11, 2024 at 3:46 PM Brandon Ambrose <bpambros...@gmail.com> wrote: > Does this apply only to customers using their proprietary gateway or > customers on a CGNAT service with them? > > I have been a Comcast customer for years, with my own equipment, and have > never had issues using Polycom SIP phones on RingCentral. > > This is getting a little concerning for me as we are planning to roll out > SIP phones direct to users at home soon. > > Brandon Ambrose > Network Administrator > On Sep 11, 2024 at 6:15 PM -0400, Matt Hoppes < > mattli...@rivervalleyinternet.net>, wrote: > > I have not, but we've run these phones with SIP ALG devices before > without issue. I'll have them check. > > On 9/10/24 9:17 PM, Tim Burke wrote: > > Have you tried placing the CPE in “bridged" mode? It’s been a while since > I’ve done anything with Comcast CPE, but I remember their CPE doing SIP ALG > when acting as a router. > > On Sep 10, 2024, at 2:17 PM, Matt Hoppes < > mattli...@rivervalleyinternet.net> wrote: > > I have an employee who has recently switched to Xfinity cable service. > Ever since they switched their internet service their work phones will not > stay registered for more than about 3 minutes. > > These same phones have been used on many ISPs without issues. The same > config has been used behind multiple levels of NAT without issues. > > She was fine, until she switched to XFinity. > > Of course, XFinity support is absolutely worthless. > > Anyone from XFinity Tier 3 or such that might be able to offer assistance? > > I suspect it's something stupid with either NAT overload in the modem or > the modem not keeping the SIP channels open. > > I've tried playing around with registration times without any success. And > again, we've never had issues with these phones or this setup with any > other ISP. > > > >
