SIP registration failure

VoIP2022

What esle needs to be done to make the sip registration successful on this Zyxel router with integrated ATA? All parameters set, even compared with a working setup from a friend but ours still don't register. What could prevent sip registration? SIP ALG is disabled. account = sip username is used. proxy server is a repeat of registrar server aand provider server. it's a Zyxel DX5401-BO supplied by B4RN who could not find anything wrong with sip settings nor with the router. more infos and screenshots can be shared in private.

tonygibbs16

Hello @VoIP2022

Welcome to the forum.

I found the user guide at https://spdl.zyxel.com/AX7501-B0/user_guide/AX7501-B0_V5.15-V5.17%20Ed%202.pdf and its section 4.6.

You might want to check all these settings.

It might be worth you checking the networking basics as well, such as being able to reach the SIP REGISTRAR Server address with Ping and Microsoft Port Query tool (see https://www.microsoft.com/en-us/download/details.aspx?id=24009 and https://learn.microsoft.com/en-us/troubleshoot/windows-server/networking/portqry-command-line-port-scanner-v2 ) to check reachability and that there is no firewalls blocking the SIP registration signalling.

- If you are successful in using the Microsoft Port Query tool and there is no reachability problems, then you should find the SIP REGISTRAR server of your VoIP provider LISTENING on TCP port 5060.

I hope that this is helpful.

Kind regards,

Tony

VoIP2022

Hi Tony,

Thanks for replying. I have to admit that I am not an IT person so won't be able to to ping or do the query thing. But I find the info on transport protocol interesting: using TCP. We are using UDP at the moment. Does that mean that UDP doesn't work on Zyxel ATA?

Also, for your information, We tried on SIP2 to setup a voip account from a different ITSP, and it worked. We then retried comparimng the fields and ours didn't work although it works in a different LAN at a different property. Yes, same sip settings failing to work here worked at a different LAN.

Should we use TCP instead of UDP you reckon?

Thanks

vv

VoIP2022

Sorry Tony,

What to enter under Account Number? Is it the sip username? What is SIP Number? Is it SIP username?

VV

tonygibbs16

Hello vv @VoIP2022

Your welcome.

SIP can work over both TCP and UDP, according to https://en.wikipedia.org/wiki/Session_Initiation_Protocol .

TCP should be more reliable in terms of the SIP signalling going through more reliably.

The voice content sent in Real-time Transport Protocol (RTP) or Secure RTP is ususally sent over UDP, because it would not cope with the retransmissions of TCP.

Thanks for mentioning that SIP2 works with a different ITSP. This is interesting.

Kind regards,

Tony

tonygibbs16

https://community.zyxel.com/en/discussion/comment/51264#Comment_51264

Hello VV @VoIP2022

The user guide says that the Account Number should be the part of your SIP URI before the @ symbol, see below.

so this might be your VoIP telephone number or it could be your name before the @ symbol, see https://en.wikipedia.org/wiki/SIP_URI_scheme for examples.

I hope that this is helpful.

Kind regards,

Tony

VoIP2022

Hi Tony,

An IT friend of mine checked and found the following:

"We can see that the router is sending REGISTERs to us every couple of seconds, but not sending any password across. Example log below.

If you can find the place the password where be set in the device settings, and add it in there (or maybe it's in there but just not set to authenticate with a password), hopefully this will register.

--------------------
REGISTER sip:davidgreenhalgh.intervoip.co.uk SIP/2.0
Via: SIP/2.0/UDP 149.86.242.41:5060;branch=z9hG4bK2441522381-2806
Route:
Max-Forwards: 70
Accept-Encoding: identity
Accept: application/simple-message-summary
Accept: application/sdp
Accept: application/dtmf-relay
Accept: application/dtmf
Accept: multipart/mixed
Accept: application/3gpp-ims+xml
Accept: application/vnd.etsi.simservs+xml
Accept: application/simservs+xml
User-Agent: ZYXEL DX5401-B0 V5.17(ABYO.0)C0
Supported: replaces,path
From: "user_umfdy1";tag=ZyXELUA_2441522488-2806
To: "user_umfdy1"
Call-ID: 2441522080-2806
CSeq: 1 REGISTER
Expires: 300
Contact: ;expires=300
Allow: INVITE,ACK,CANCEL,BYE,OPTIONS,REFER,INFO,PRACK,NOTIFY,MESSAGE,UPDATE
Content-Length: 0
-------------------- "

Why is it not sending password? what could be the reason?

tonygibbs16

Hi vv @VoIP2022

Ok.

I think that the User Guide says that user name and password should be entered under Authentication under VOIP>SIP>SIP Account , see below.

When it works then the SIP REGISTER is usually answered with a 401 Unauthorised message, which then asks the Phone/ATA to send another SIP REGISTER message but with the addition of an authentication header made up from the user name and password, see https://blog.wildix.com/understanding-register-method/ for examples of the signalling.

If the registration is successful, then the ITSP should reply with SIP message 200 OK .

I hope that this is helpful.

Kind regards,

Tony

VoIP2022

Hi Tony,

Thank you so much but what to use under SIP ACCOUNT NUMBER then? the telephone number associated with this voip user?

VoIP2022

Can we leave SIP ACCOUNT NUMBER blank? we ahve:

• a username: john002
• a password: 123456
• host: jonh002.serviceprovider.co.uk
• transport protocol: UDP —- > should we change to TCP only?
• DNS mode: SRV

These are all we have in terms of sip settings

VV

tonygibbs16

Hello vv @VoIP2022

You're welcome. Yes I think so, which should be that before the @ sign.

Kind regards, Tony