Matthias Wimmer <[EMAIL PROTECTED]> wrote
>Hi Tijl! > >Tijl Houtbeckers wrote: > >>A few problems I see with using keep-alives (as far as I understand them) >>1. It is very low level, not all programming languages / devices will have acces to >it. >> >It's right that not every programming language support activating >keep-alives, but: >- you only have to activate it at the server >- you don't have to do anything on the client it's completely >transparent to it >- it's accessible by much more programming languages then the OOB data True, I never considered OOB data though.. >>2. It is bound to TCP/IP, I could for example use a bluetooth link or a serial link instead >>of TCP/IP. Jabber over HTTP also sort of falls into this catagory. >> >TCP keep-alives aren't and won't be needed by the Jabber protocol. It >just solves some problems we have with TCP. Therefore we only need it >with TCP. Well, it's a problem in manny connection oriented enviroment, not just TCP/IP.. if we start using keepalive will people say: we've got the solution now, so why bother on making something on the jabber protocol level (or support it)? >>3. keep alive is OS dependant. Not all OSes provide acces to it, and some let you set >>it only for all applications, not specific ones (as I understand from earlyer >postings). >> >On the one hand I know no operating system that doesn't support it, on >the other hand you only need support for it on the server side. Hm, I suppose you're right here, there's not manny operating systems left that don't support it, and the ones I can think of you probably would not want to run a jabber server on anyway. >>4 I asume keep-alives will be for *all* user that log into jabber, some might not want >>keep-alives or anything like it at all for their clients. >> >As I told: It's completely transparent to the client. The only thing why >he couldn't like it is that the client has very expensive metered >traffic. For this clients would be possible to include some way to >disable keep-alives (the server can activate and deactivate keep-alives >per connection). > But as I wrote above: It is a very small amount of >additional traffic and it's only generated on idle connections. Every >other way to fix our TCP problems will generate more traffic. > >>A few of these problems came up before on the mailinglist, and I haven't yet heard a >>solution for them. It might not hinder any implemention for this on *nix, but the >>problem will still remain for the platforms/implementations that can not use this. >> >We have servers on Unix, Windows and Java. All of this three platforms >support keep-alives (Java since version 1.3). The client side is >supported by every platform/language that supports TCP/IP. I suppose my worries were a bit overstated, keepalives sound like a good solution (should they be opt-in or opt-out?). I hope they won't screw up my GPRS links but I don't think so.. I doubt there that manny implementations of jabber over something else as TCP/IP anyway, we'll just have to cross that bridge when we get there.. -- Tijl Houtbeckers JAVA/J2ME/GPRS Programmer @ Splendo _______________________________________________ jdev mailing list [EMAIL PROTECTED] http://mailman.jabber.org/listinfo/jdev
