[LINK] WebSockets

Roger Clarke Roger.Clarke at xamax.com.au
Wed Mar 30 22:48:54 AEDT 2011

At 22:28 +1100 30/3/11, Johann Kruse wrote:
>WebSockets-like functionality has definitely been around for some time...

Tickertape since 1996 for starters.  Although it died, so I guess it 
isn't around.  Fair enough.

>For example Exchange Activesync (aka EAS) which is the push-email
>protocol used by Exchange, iPhone, Android, Windows Phone, etc was
>introduced around 2005.
>EAS uses an extended time-out HTTPS session so that the client
>maintains a connection to the Exchange Server, which can then
>instantly respond to the already-open session when new email arrives.
>Because the client is listening but not sending any traffic until the
>timeout, there is no excess bandwidth consumption.
>It's not WebSockets - but to the end-user it's the same effect.

What's an "extended time-out HTTPS session"?

Aren't sessions established and run at the next level, TCP?

So all this is is a long TTL?

That probably wasn't in Vint Cerf's original spec in 1982-83, but I 
suspect that it long predates the Web, and is independent from it, 
even in its intellectual origins?

Sorry, but it's too late at night for an old bastard to do his 
homework and run the history of TCP TTL to ground  (:-(}

Roger Clarke                                 http://www.rogerclarke.com/

Xamax Consultancy Pty Ltd      78 Sidaway St, Chapman ACT 2611 AUSTRALIA
                    Tel: +61 2 6288 1472, and 6288 6916
mailto:Roger.Clarke at xamax.com.au                http://www.xamax.com.au/

Visiting Professor in the Cyberspace Law & Policy Centre      Uni of NSW
Visiting Professor in Computer Science    Australian National University

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