Good ol UDP encrypted.
On Mon, May 13, 2019 at 12:49 PM Brielle Bruns <br...@2mbit.com> wrote: > > On 5/13/2019 10:20 AM, Dovid Bender wrote: > > Thought of that. Customers have their own CPE's. So far the only thing > > mutual here is that it's NTT -> VZ. Here is what I found so far looking > > at two Polycom phones using non standard ports (e.g. not 5060) > > 1) PhoneA tries to register multiple extensions and for each request we > > send a 401. We expect to get back a REGISTER request with a no-once but > > we don't. This happens for a while and then magically it starts working. > > 2) PhoneB tries to register the time time as PhoneA and has no issues. > > > > At first I thought it was something possibly with the SIP call-ID but I > > ruled that out since in the same SIP DIALOG it was not working then it > > started. Also the seems to be per phone each phone is behind NAT and the > > traffic is coming from a different NAT'd port. Seems like there is some > > device in the middle that is randomly dropping traffic on specific > sessions. > > > Are you using TLS encrypted SIP or just plain ol' cleartext? > > If its encrypted, I'd look at possibly there being a MTU/MSS issue > somewhere along the path possibly? > > > -- > Brielle Bruns > The Summit Open Source Development Group > http://www.sosdg.org / http://www.ahbl.org >