In the scenario that I do, I have to use transparent mode, because the authentication is done on Asterisk servers.

And for this issue, (using the same CSeq) the authentication process is not successful.

So, I have to manage the value of CSeq by Kamailio or have some update in Sems so that at least could relay the Cseq without changing.

What do you think?

On Sun, Dec 19, 2021 at 5:09 PM Juha Heinanen <jh@tutpro.com> wrote:

Mojtaba writes:

> Yes, I agree with you, This is an exception related to 401(Unauthorized)
> and 407 (Proxy Authentication Required) responses.
> In these situations, The CSeq header field value should be
> incremented.

SEMS SBC does support SIP authentication, but looks like not in
transparent mode. From Readme.sbc.txt:

SIP authentication
------------------
The SBC can perform SIP digest authentication. To use SIP authentication, the
uac_auth module needs to be loaded.

SIP authentication is enabled by the following parameters, separately for both
call legs:

# Authentication for B leg (second/callee leg):
enable_auth "yes" or "no"
auth_user authentication user
auth_pwd authentication password
# Authentication for A leg (first/caller leg):
enable_aleg_auth "yes" or "no"
auth_aleg_user authentication user
auth_aleg_pwd authentication password

Note: The 'A' leg is always the first leg, the one from the caller. 'B' leg is
the one to callee:
caller <--- A (first) leg ---> SEMS <--- B (second) leg ---> callee

Example:
enable_auth=yes
auth_user=$H(P-Auth-B-User)
auth_pwd=$H(P-Auth-B-Pwd)
enable_aleg_auth=yes
auth_aleg_user=$H(P-Auth-A-User)
auth_aleg_pwd=$H(P-Auth-A-Pwd)

Perhaps yeti-switch/sems-yeti can do it also in transparent mode.

-- Juha