Subject: DLSw keepalive messages

From: [email-masked] (Dragan Tosic)
Date: Tue, 2 Apr 1996 05:17:56 -0800 (PST)

Hi there

can you pls try to answer following question :

Is KEEPALIVE message (16 bytes) being sent
per DLSw connection or is it sent per peer ?

Also I would like to know what is time interval between
KEEPALIVE messages ?

TIA
D.B.Tosic VIAG Interkom (BT Germany) TechSupport Group

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From: [email-masked] (Tony Clark)
Date: 02 Apr 1996 14:20:54 GMT

Tony Clark is currently out of the office on business and will not return
until Friday, April 5th.

If your message is urgent, please contact Jim Vogt at (408) 764-1293 or
Brenda Kamrar at -7687.

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From: [email-masked] (Alan Bartky)
Date: Thu, 4 Apr 96 18:42:12 PST

> From [email-masked] Tue Apr  2 05:38:04 1996
> Date: Tue, 2 Apr 1996 08:32:32 -0500
> Reply-To: [email-masked]
> Originator: [email-masked]
> Sender: [email-masked]
> From: [email-masked] (Dragan Tosic)
> To: [email-masked]
> Subject: DLSw keepalive messages
> X-Listprocessor-Version: 6.0c -- ListProcessor by Anastasios Kotsikonas
> X-Comment:  DLSw
> Content-Length: 284
> 
> Hi there
> 
When we were drafting the spec. we added the KEEPALIVE function
( I believe some vendor thought it would be usefull and/or already
had the function).  We did not intent to fully document it
as it was to be fully optional and not required to run the protocol.
It was only to verify that a particular TCP connection was still functioning.
The only text in the RFC is in Note 4 after the summary of 
DLSw messages:

   Note 4:  A KEEPALIVE message may be sent by a DLSw to a partner DLSw
   in order to verify the TCP connection (or other future SSP carrying
   protocol) is still functioning.  If received by a DLSw, this message
   is discarded and ignored.  Use of this message is optional.

My reading of the text (and my recollection) was that it is per
TCP connection and not per SSP connection.
  
> Also I would like to know what is time interval between
Since it was optional, we did not specify a time interval in the
specification.  If you are seeing it from a particular vendor's
product, you will have to get their timeout value from them.
There is nothing in the standard to specify any timeout values.
 
> D.B.Tosic VIAG Interkom (BT Germany) TechSupport Group

Hope this helps,

Regards,

Alan

**********************************************************
Alan K. Bartky                       Email:[email-masked]
Principal Software Engineer
XYLAN Corporation                    Voice:(714) 597-8042
15707 ROCKFIELD BLVD STE 155F        FAX:  (714) 597-8342
IRVINE CA 92718-2830
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