SIP settings for VOIP with O2

[oliverpool]

I've been able to manage a stable internet connexion with O2 (see #12 (comment)), thanks again for this wonderful guide!

I'm still struggling for the SIP settings.

This are the parameter given by O2:

SIP-server: sip.alice-voip.de
Rufnummer: 089/12345678
SIP Benutzername: 498912345678
SIP Passwort: ******

Be careful: the font used makes the l and the I (uppercase i) look the same!

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At the beginning, the box couldn't register to the SIP server. For the registration to succeed, I had to use the following parameters:

lineEnable@sip_acc_1 = 1
userId@sip_acc_1 = 498912345678
userId_area@sip_acc_1 = 089
userId_local@sip_acc_1 = 123456789
account_name@sip_acc_1 = 08912345678
displayName@sip_acc_1 = 08912345678
password@sip_acc_1 = ******
useAuthId@sip_acc_1 = 0
authId@sip_acc_1 =
realm@sip_acc_1 =
sipdomain@sip_acc_1 = sip.alice-voip.de
registrar@sip_acc_1 = sip.alice-voip.de
proxy@sip_acc_1 = sip.alice-voip.de
outboundProxy@sip_acc_1 = sip.alice-voip.de
useOutboundProxy@sip_acc_1 = 0

Important things are probably:

• the realm must be empty
• the userId must start with 49 (instead of the 0)
• new settings are taken into account only after a reboot (which lasts around 5 minutes...)

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Now the box successfully registers the SIP number (the status is shown as Aktiv on http://easy.box ), but when I try to make a call, it doesn't work.

Running tcpdump -nni any -s 0 udp -vv on the box, allows to capture the SIP packets and see that the INVITE command sent by the box receives a 500 Internal Server Error from the server (whereas the previous REGISTER command succeeded).

Comparing it with packets captured during a successful session (made with the SessionChat app by a phone connected to the box via wifi) didn't give me a clue to fix this...

I don't really need the phone to work via the box (and I think that I won't digg further), but maybe my findings will help other people go further :-)

[majuss]

Hi Oliver, thanks for all these infos on O2!

Maybe the DSCP settings need to get changed? https://en.wikipedia.org/wiki/Differentiated_services / https://hilfe.o2online.de/thread/160458-dsl-ac87vg-und-voip

Unfortunately I can only help in a very limited way since I don't have an O2 access. Interesting would be which 500 is getting thrown...

Interesting enough: https://hilfe.o2online.de/thread/41360 they use completely other domains.

[oliverpool]

thanks for all these infos on O2!

You're welcome! Your guide already had most of it :-)

Interesting enough: https://hilfe.o2online.de/thread/41360 they use completely other domains.

Maybe O2 changed their domains (the thread is from 2010).

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Unfortunately I can't test any further: the easybox is now used for a Telekom connection (VDSL & VOIP work perfectly with the settings recommended by your guide) and I took the Fritz!Box (which was used there) for the O2 connection ;-)

[DDvO]

I can basically confirm the SIP settings for o2 given above.
Yet the account_name@sip_acc_1 may be anything (user-defined)
and the displayName@sip_acc_1 value seems not to be shown anywhere, so can be left out.
The value of sipdomain@sip_acc_1 is irrelevant.
Also the outboundProxy@sip_acc_1 can be empty because it seems to get ignored,
regardless whether useOutboundProxy@sip_acc_1 is 0 or 1.

In other words, only the following is relevant (and the rest can be left with default values):

ccfg_cli set lineEnable@sip_acc_1=1
ccfg_cli set userId@sip_acc_1=4989xxxxxxxx
ccfg_cli set userId_area@sip_acc_1=089
ccfg_cli set userId_local@sip_acc_1=xxxxxxxx
ccfg_cli set account_name@sip_acc_1=+4989xxxxxxxx  # anything user-defined
ccfg_cli set password@sip_acc_1=yyyyyyyyyyyyyyyy
ccfg_cli set realm@sip_acc_2=                      # must be empty
ccfg_cli set registrar@sip_acc_2=sip.alice-voip.de
ccfg_cli set proxy@sip_acc_2=sip.alice-voip.de

[DDvO]

With the given settings the SIP login works fine on reboot of the box,
and incoming calls also work fine.
Yet for outgoing calls I also do not get a connection but some immediate error tone in case dtmfTxMethod@sip_acc_1=0 or empty or some kind of timeout after 30 seconds in case dtmfTxMethod@sip_acc_1=1 or 2.

For each call the event log of the box gives [VoIP] Incoming Call (No Ack For 2xx) Account 1.
The same holds BTW for a sipgate accout I've been trying out alternatively to o2.

This seems a common problem - see,
e.g., https://www.3cx.com/community/threads/ack-is-not-received-from-sip.32989/
and https://blog.opensips.org/2017/02/22/troubleshooting-missing-ack-in-sip/

[DDvO]

I wonder why this issue has been closed - the problem is not solved.
Or does anyone have a solution?

Note that the problem not only pertains to o2, but also to sipgate and 1und1 (see also #25).
I suspect that it is a general problem with configuring VoIP via the Easybox 904 CLI.

[DDvO]

I've given up on the crappy EasyBox 904 firmware. Trying to get SIP calls working was a total waste of time. Apparently nobody has competence on this topic.
Moreover, the DSL connection of the box hung about once a week and required a reboot.

I meanwhile got a FritzBox 7430, where everything just works fine, without any hassle.

[ehrenmann1977]

In fritzbox i have a drop down menu with O2 as telephony provider, but i don't know what is the internal setting of the server.