Express Talk Delay

[masonpj]

I have set up AVPBX and express talk on one pc, and express talk on another on my Lan. connected via d-link G604T wireless router. all required ports forwarded to static IP on main pc.

 

Calling from ET on PBX machine (ext 101) to ET on other (ext 102) is instant and other PC can pick the call up ok. all works as it should.

 

BUT calling from 102 to 101 takes about 20 seconds to connect and when 101 picks up, the call is dropped.

 

Where should I look for the answer?

 

Cheers

[masonpj]

Ive just re-run the network wizard, and while the delay is still 20-30 seconds, at least the call is staying connected!

 

I still need help.

 

Cheers

[pythonpoole]

Usually I have a solution for everything, but this one perplexes me. Usually these types of problems are indicative of a network communication issue, but you have already forwarded the necessary ports and run the network set-up wizard; that rules out most network communication problems. It's also very strange that calling from 101 to 102 works perfectly but viceversa causes a problem.

 

Do you experience similar problems when using another softphone (e.g. X-lite or SJPhone)?

[masonpj]

BY AVPBX I mean Axon Virtual PBX.

 

3CX VoIP client works fine. (Disconnect slightly slow - maybe 3-4 rings) I'd use it, but it doesn't have a contacts/address system

 

When express at 102 logs in, it takes 30 seconds, displays a connection error as follows.

register authorisation failed for sip:102@officepc

error returned: 401 unauthorised

check username or password for the proxy server

 

then it connects:

registered as: sip: 102@officepc

 

A Call takes 25-30 sec to connect. On hangup, it takes about 15 seconds to disconnect.

 

????

[masonpj]

Since I tested with 3CX Client, I am now getting error messages on express (102) telling me the stun servers failed, and to check that port 5070 is not being blocked at the local firewall. The ports have all been opened on windows firewall but I disabled the firewall anyway (firewalled on router).

 

I don't understand the port forwarding thing.

I have set my main PC up with a static IP (10.1.1.4) and forwarded ports (including 5070) on the D-link router to that address.

Express at 102 also uses port 5070. How does it pick up port 5070 then? How is that separate to the forwarded router port? Is it listening on that PC's port 5070? In which case, why does express think it's blocked when the firewall on that machine is disabled?

 

Thanks for your help.

[pythonpoole]

I believe the correct Port Forward mapping is to forward the SIP port used by each different extension to the particular computer/device that extension is on. I.E. if Axon on PC1 is using 5060, forward 5060 to PC1.. If Extension 102 with port 5070 is on PC 2, forward 5070 to PC2. Keep in mind though that I don't think WAN to LAN port forwarding will help much for internal calls, I think it's more to help calls to/from your VoIP provider.

 

Note: Failure to connect to the STUN servers is often indicative of firewall port blocking / incorrect port forward set-up. You can also use UPNP as alternative. UPNP is not available on all routers, and even on the routers that support it, the functionality is sometimes limited. Having said that, UPNP is a great feature in theory that helps take all the hassle out of port forwarding and network set-ups. I don't know exactly how it works but my understanding is it allows free communication through the firewall on specific ports used by the software (auto port forwarding?).

 

Also make sure that your internal network (LAN) is not blocking anything (or at least not any ports related to Express Talk).. if your network is for home or a small business, there really shouldn't be a need for a LAN to LAN firewall as most if not all the communication between PCs in your network would be trusted. In any case, this sounds like it could be one of the major problem(s) you're having as the difficulties you are experiencing are all internal.

 

Lastly, it is very unusual for Express Talk to report "error returned: 401 unauthorised" and then register fine later using the same username/password. I have yet to come up with a plausible explanation to this, it's almost as if line interference is causing corruption to the SIP messages so they have to be resent several times before they get through (would also explain the delay?). Perhaps blocked ports can cause similar issues.

 

Since I haven't come across these problems before, it's hard for me to identify exactly what the source of the problem is. But it seems to me the most plausible explanation is either blocked ports on the internal LAN and/or packet corruption possibly due to interference and/or network issues. Line interference doesn't sound right though since you mentioned calling 102 from 101 doesn't cause any problems.

[GolaYing]

so bad, I don't like AVPBX, I use skype.

[pythonpoole]

@Gola Ying, Skype and Axon are nothing alike in the purpose they serve.. it would be impossible to compare them.

 

Axon/AVPBX is used to manage call routing and determine how incoming and outgoing calls should be handled. It also allows you to connect several VoIP phones or soft phones to the same VoIP lines and share them as well as offer inter-extension dialling.

 

Skype is simply a proprietary VoIP client (soft phone) that lets you make and take VoIP phone calls through the Skype network.

 

The only thing similar about the two is that Axon allows you to connect soft phones to itself which are similar to Skype clients in a way.

Axon is more like the server that runs the whole Skype network if anything else.