Glenn Maynard wrote 2011-07-20 05:53:
> It would be beneficial if there was *some* standardized way to send
a keepalive packet in less than 70 bytes
TCP keepalives do that; they're nothing but an empty TCP packet with a
redundant ACK, to cause a keepalive with the minimum possible packet
size and without inserting garbage into the stream.
Some conclusions can be carried over from the same discussion for SIP,
documented in RFC 5626
http://tools.ietf.org/html/rfc5626#section-4.4.1
There, the keepalive frequency for TCP is recommended to be 14 minutes
for the mobile case and the keepalive packet contents is recommended to
be CRLF.
/Gunnar
