On 12/06/2013 12:33, Tim Bray wrote:
On 12/06/13 11:58, Nigel Titley wrote:
Does anyone have recommendations for helpful and reliable VOIP services
providers in the UK. We're currently on a Gradwell hosted PABX solution
but it's been getting more and more unreliable and we are now starting
to get customer complaints: queued calls are being dropped before the
phones ring, phones unregister randomly and I get emails telling me
phones have unregistered when they haven't, I can't block incoming SIP
hack attempts because Gradwell can't guarantee what IP address incoming
calls will come from, they don't do IPv6 etc
Gradwell are good guys. I know they had a bit of a platform move
hipcup. But I'm sure general issues can be worked through.
I've been with Gradwell for many years. I used to run my own asterisk
box with an IAX trunk from Gradwell and all went fine for a long time.
Then suddenly it stopped working and we couldn't get the trunk back up
again. Eventually after a couple of days with no phone service we caved
in and bought a managed solution from them.
Which phones are you using? Managed by gradwell? All up to date
firmwares etc? If you have snoms, then loads of diagnostics can be
done to work out whether some SIP Alg or network issue.
It's a mix of Siemens and Grandstreams. All the firmware is up to date.
They've been working fine for a long time.
Randomly un-registering phones could simply be your phones are set to a
too short registration expiry and a too long registration retry. SIP
registration can be vulnerable to losing 1 packet out of 4 in the exchange.
So a failed SIP registration doesn't get retried before the original
registration has expired. This is very common, and usually in the
face of registration problem people seem to have this habit of setting
the SIP expiry to a very low value like 60 seconds.
Out of the box Snom phones have a retry interval of 5 minutes. If you
set your SIP expiry to 1 minute, then a single packet lost could mean 4
minutes of no registration before it retries.
The SIP expiry is several hours and the retry is about 5 mins as I
recall. Phones randomly unregister and then don't seem to come back. I
suspect this isn't a Gradwell issue as it's only the Grandstreams that
do it. What has been more annoying is Gradwell sending me emails telling
me all my phones have unregistered when they haven't.
What is finally making me think about moving is really a combination of
three issues:
1. Incidents that are happening more and more frequently of calls
incoming, queuing, ringing the hunt group once or maybe twice and then
dropping. We've rung the customers back and they say the call just drops
on them. A variant on this is a call a couple of days ago which hung on
the queue for four and a half hours resulting in a bill for *us* of over
£20.
2. The aforementioned unregistrations
3. The fact that Gradwell can't tell us what IP address incoming calls
will come from, which means I can't block incoming SIP attacks.
and it's no good ringing up their support line because the phone just
rings and rings...
I'm not going to recommend a VoIP provider because lots of them are my
customers and I don't like to recommend one above another.
That's fine and understandable
The ITSPA members list is a good place to start
http://www.itspa.org.uk/members.shtml Some people on here are more
wholesale.
Thanks
Nigel
Tim
