[Serdev] SER as an extendable codebase/SIP stack - was: So who/what is SER for, anyway?

[Andrei Pelinescu-Onciul]

On Jan 25, 2007 at 09:33, Greger V. Teigre <greger at teigre.com> wrote:
> Greger's comment: I interpret the first part of Dragos post as a 
> frustration related to using SER's code base to realize another 
> SIP-related application, i.e. using SER instead of a SIP stack. Thus, I 
> call this thread: SER as an extendable codebase/SIP stack.
> ---------------------------------------
> Hi all,
> 
> I am not sure if I should start this thread or not... recently some heat
> came up on the dev list ("usrloc loading") and the most important thing
> out of it (and neutral, because somehow the discussion included stuff
> like ser vs openser) is what Greger blogged here
> http://sipstuff.blogspot.com/2007/01/who-is-ser-for.html . I wouldn't
> have replied to any of it, but Greger pointed out that SER became the
> basis for other projects, like the Open IMS Core that I am working on at
> the moment and if SER's developers noticed us, maybe our experience and
> opinions might be of interest to them. (And the Open IMS Core is not the
> only one, not even the only IMS CSCF one...)
> 
> Some of you might receive this as SER bashing. But please understand
> that I only want to point out the parts that I, for one, really hate, in
> the hope that the future would bring something good. I think that SER is
> a wonderful piece of software, but it just shows it's age and has some
> cans of worms here and there.
> 
> So for the past years I have been working and playing with NGN concepts.
> Part of my work are some SER modules + scripts that would enable the use
> of SER as some sort of basic IMS CSCFs. However, the most annoying thing
> that I had to deal with is SER's "design". Whenever something does not
> work, you need to make changes in too many places and then suffer the
> consequences as you will surely break something else. With every new
> feature that you want to put it, you have to think about redesigning
> parts of SER. When you look at the code, you can understand the reasons
> for sure - like performance. But if you do not have a lot of
> digging-experience through SER's code, you won't be able to do much.Then
> it is almost impossible for me to assign even simple tasks to beginners
> and as such our progress is extremely slow.

You need to understand one thing: ser was designed as a sip proxy (and
not sip stack or for IMS) and the primary goals were/are portability
(unix / posix) and performance.
As far as one change breaks too many places I don't think this is
generally the case. There are sensible parts, but also a lot of almost
independent sections.
Yes it's hard for beginners particulary since there is close to no
development documentation. Unfortunately this won't change in the near
future since user/config documentation has a much higher priority and
that's missing too.



Andrei