Fw: [Users] TM : retransmission timers

Kim Il kim_il_s at yahoo.com
Thu Nov 9 18:40:38 CET 2006


Tavis, 

sure, I knew that SER was not stopped but it seems a lot of others believed this and I was over voted, Nevertheless, thisis not the topic of the discussion.
I am really glad that people are coming out and discussing the real merits
and I hope this will lead to a better understanding of the two camps

bye
Tavis P <tavis.lists at galaxytelecom.net> wrote:

You mentioned that you switched to OpenSER because "rumor spread around
on the openser lists that SER is no longer being maintained", i havn't
heard this rumor but a simple glance at the CVS commit logs for the SER
repositories would have shown this to be true or not (in this case,
not).  This is a very dangerous reason to switch!

I feel that both the SER and OpenSER teams are working hard on both
"cosmetic and superficial changes" as well as "real improvements" and
that is inaccurate to say that either is focusing on primarily on one of
those things. 
SER is about to release a huge update to their software, containing a
large number of additions, some inspired by work done on OpenSER, some
completely new, its a certainty that you will see a similar occurrence
in OpenSER once the new version of SER is released.  Its only natural to
build off of others work, it is what i regard to be humanities single
biggest strength

Now OpenSER was created for a reason, and i'm certain that this
reasoning still stands (if you havn't, i would urge you to read about it
here:
http://openser.org/index.php?option=com_content&task=view&id=40&Itemid=61).
If your requirements were met by the SER code base and their direction,
time lines and philosophy aligned with your own, then rumors should not
be enough to unsettle you.  SER and OpenSER are both very solid projects
(in my opinion) however they have different characteristics as such as
better suited for different environments and situations.  Regardless,
the full merits of both applications should be evaluated when
determining which to use for a project, not just surface level
characteristics

I anticipate staying with OpenSER because of their short release cycle,
eagerness to add features to their software and their direction, i'm
certain that the upcoming release of SER will be very compelling (and of
very high quality) but i already have plans in place following the
OpenSER timelines (i'm very eager to begin writing modules to make use
of the dialog module, i think this is really the killer app for OpenSER)
however my requirements are fairly large and unique so they in no way
apply to everyone


my few thoughts =D

tavis



Kim Il wrote:
> Mike,
>
> thanks a lot for your insight and the time you have taken to answer my
> question. I surely did not want to be unafir to anyone.
> I can not comment on the why the SER people are having only few
> releases compared to openser but I guess they have a good reason for
> that (I would guess it has something to do  with thoroughness, testing
> ..., but I am here just guessing).
> For me and I guess many other people who depend on SER/openser for
> their business the more interesting question is what to use in the
> long term, which camp is the more innovative, is actually driving the
> change and is commiting itself to the really difficult tasks. Your
> statement that changes in SER have been  in response to openser is
> surely a very good starting point -and if this is true then there is
> no reason to shift back to SER. Do you, or maybe other people, have
> more examples -besides the web page- for this. This will really help
> me to better judge the situation. Looking at the release notes of both
> openser and SER I am still of the opinion that compared to the new
> features of SER, most of the features that were added to openser in
> the last year are of cosmetic nature (hardly any touches the tough
> issues of security, performance and reliability).
>
> Yours sincerely
>
> Kim
>
> */Mike Williams /* wrote:
>
>     Kim,
>
>     I don't think that's really a fair assessment of the situation. It
>     seems to
>     me, and others much more knowledgeable please comment on this,
>     that OpenSER
>     was forked because SER was left to stagnate, and because of a
>     large number of
>     feature patches that were just left to sit. The development cycles
>     became too
>     long, and it was unclear what the plan was.
>
>     Looking back on the progress of OpenSER, one can see that the team
>     didn't just
>     take those patches and merge them, and pretend that they have a
>     new product,
>     but have instead continually developed the code base. The always
>     have a
>     roadmap of the next release, and an estimated timeline for
>     completing it. A
>     lot of important features have been added.
>
>     Likewise, OpenSER seems to be using a different development
>     philosophy. The
>     OpenSER team releases .1 increment releases with new, useful, and
>     stable
>     features fairly often instead of waiting years. Since I've been using
>     OpenSER, I've seen 3 releases. SER has put out 1 in that same time
>     period,
>     and honestly, I don't see the same amount of features really being
>     added by
>     SER. If anyone can compare the two in their present STABLE forms,
>     I would
>     really like to hear about it.
>
>     In addition, it seems many of the changes to SER have been in
>     response to
>     OpenSER. Iptel/SER had the same website for years, with little
>     information
>     about what was actually happening. If you check the OpenSER
>     website, they are
>     always giving useful information and news to the users and
>     community about
>     going forward. Just in the last few months has Iptel/SER actually
>     changed, no
>     doubt partly due to how good OpenSER looked in comparison.
>
>     Mike Williams
>
>     On Wednesday 08 November 2006 04:06, Kim Il wrote:
>     > thanks Rao for bringing this up. Actually our company has moved
>     to openser
>     > around 6 months ago after reading the rumor spread around on the
>     openser
>     > lists that SER is no longer being maintained. Looking now at the
>     new SER I
>     > must confess that we are more than impressed about the new
>     features and
>     > substantial changes to SER. It seems that, unlike openser,
>     > the guys
>     > behind SER spent the time not on cosmetic and superficial
>     changes but on
>     > real improvements. I assume this difference in working style
>     comes from the
>     > fact that openser is lead by a company that is capitalizing the
>     open-source
>     > spirit to satisfy the day-to-day needs of it customers whereas
>     SER is being
>     > maintained by guys who have a long term vision of things. While
>     it will
>     > surely cost us some time and effort for us the decision is
>     already clear
>     > that unless openser integrates the SER improvements we will go
>     back to SER.
>     >
>     > Bye
>     >
>     > Kil Il
>     >
>     > Rao Ramaratnamma wrote: sorry for reposting -- I
>     > think this question belongs to both mailing list. I am really
>     stuck with
>     > this.
>     >
>     > rr
>     >
>     > ----- Forwarded Message ----
>     > From: Rao Ramaratnamma
>     > To: Christian Schlatter ; users at openser.org
>     > Sent: Tuesday, November 7, 2006 11:15:27 PM
>     > Subject: Re: [Users] TM : retransmission timers
>     >
>     > the ser ottendorf announcement does mention improved timers.
>     Cannot openser
>     > include this feature too and cannot I merge ser with openser for
>     good
>     > timers? I am still trying to understand the difference between
>     ser and
>     > openser but standart compliance seems to be very important matter!
>     >
>     > Cannot people provide me with some hints? I am sure that I am
>     not the only
>     > who is asking the difference between ser and openser. ser
>     documentation
>     > does not appear uptodate, but the software as sannounced appears
>     > impressive. I have already asked this question but did not
>     receive any
>     > answer.
>     >
>     > thank you in advance!
>     >
>     > rr
>     >
>     > ----- Original Message ----
>     > From: Christian Schlatter
>     > To: users at openser.org
>     > Sent: Tuesday, November 7, 2006 10:52:56 PM
>     > Subject: Re: [Users] TM : retransmission timers
>     >
>     > Greg Fausak wrote:
>     > > Hello,
>     > >
>     > > I believe this is a well known bug.
>     > > Granularity of timers is 1 second. So, if you sign up for a
>     timer to
>     > > be fired in 1 second it will happen anywhere between 0 seconds
>     and 1
>     > > second.
>     > > 2 seconds will happen between 1 and 2 seconds. I usually set up my
>     > > timers to be 2, 2, 4, 8. There are VOIP providers that are pretty
>     > > sticky about
>     > > the first 500ms. If you are using one of them you're out of luck.
>     >
>     > Yes, there is a timer process that wakes up every second to perform
>     > retransmissions. I was actually quite surprised that OpenSER,
>     which is
>     > known to be very standards compliant, does not follow the RFC 3261
>     > retransmission timeouts. On the other hand, the RFC 3261 timeout
>     values
>     > are just suggestions and standards compliant SIP UA must accept
>     shorter
>     > timeouts. Still it would be nice if OpenSER would support sub second
>     > timers, this would allow for shorter fail-over times.
>     >
>     > Christian
>     >
>     > > I believe SER has made timer changes to support more exact timer
>     > > intervals. They are a completely different camp, with a different
>     > > feature set (although they share the same roots).
>     > >
>     > > -g
>     > >
>     > > On 11/7/06, Jean-François SMIGIELSKI wrote:
>     > >> Hello,
>     > >>
>     > >> I made strange observations about the intervals between
>     > >> retransmissions with the TM module.
>     > >> In my experiments, I used the default parameters for the TM
>     module
>     > >> timers, and I sent an INVITE that cannot receive answers (it
>     has a
>     > >> well known R-URI pattern that is forwarded to a place and
>     port that
>     > >> nobody listen).
>     > >>
>     > >> When reading RFC3261, I expected to see intervals between
>     > >> retransmissions of |500ms|1s|2s|4s|8s|16s|. 7 transmissions,
>     during 32s.
>     > >>
>     > >> But with OpenSER, (I have tested with the debian package
>     1.1.0-5 on a
>     > >> debian etch, and the cvs sources for 1.1.0 or 1.0.1compiled by
>     > >> myself), I can see intervals like <500ms, 2s, 4s, 4s,4s, ...
>     until 26s
>     > >> are spent (9 sendings). The first interval is sometomes very
>     short
>     > >> (40ms).
>     > >>
>     > >> Altough I like the sequence of 4s separated transmissions, I
>     do not
>     > >> know why the first interval is so short, and why there is no
>     sending
>     > >> after 1s.
>     > >>
>     > >> Did anybody observed such behaviours? Are they normal?
>     > >>
>     > >> Thanks in advance!
>     > >>
>     > >> JF Smigielski.
>



 
---------------------------------
Everyone is raving about the all-new Yahoo! Mail beta.
-------------- next part --------------
An HTML attachment was scrubbed...
URL: http://lists.kamailio.org/pipermail/users/attachments/20061109/967324eb/attachment.htm 


More information about the Users mailing list