[jdev] XMPP Ping/Keepalive: Recommended method ?

[Dave Cridland]

On Sun Jul  2 02:02:03 2006, Joe Hildebrand wrote:
> Ah, I misunderstood what your negative was about.  I thought you 
> were  saying that the ACKs don't make it back. :)
> 
> 
Of course, arbitrary destruction of established TCP connections by a 
man in the middle is, arguably, also breaking TCP.


> On Jun 28, 2006, at 3:04 AM, Bruce Campbell wrote:
> 
>> On Tue, 27 Jun 2006, Joe Hildebrand wrote:
>> 
>>> Date: Tue, 27 Jun 2006 05:59:54 -0600
>>> From: Joe Hildebrand <hildjj at gmail.com>
>>> Reply-To: Jabber software development list <jdev at jabber.org>
>>> To: Jabber software development list <jdev at jabber.org>
>>> Subject: Re: [jdev] XMPP Ping/Keepalive: Recommended method ?
>>> On Jun 27, 2006, at 4:09 AM, Bruce Campbell wrote:
>>> 
>>>>> Well, not really.  You'll get a TCP ack back, which should be  
>>>>> enough to keep the lights on.
>>>> Not if you are dealing with inspection-type firewalls which 
>>>> don't  really treat a TCP ACK as a data packet.
>>> 
>>> If firewalls did this, TCP would *break* for all applications.   
>>> Can you please give a concrete example of a firewall that has 
>>> this  property?
>> 
>> Not a firewall appliance, but 'interesting' configurations with  
>> ISPs seeking to keep their dial-up lines/wavelan channels free  
>> (timers on their end were only reset on certain types of packets,  
>> which did not include tcp acks).

I find it notable that the same people who're ensuring that a live 
connection has to transfer data to stay alive tend to be the same 
people who charge for transfer instead of time.

Of course, they're severing my running connections, thus incurring 
additional data transfer, which they then charge for, purely for 
sound technical reasons, and not to fleece me for every penny I have.

Dave.
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