Re: [hybi] Call for interest: multiplexing dedicated for WebSocket

Tobias Oberstein <> Mon, 27 May 2013 11:59 UTC

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From: Tobias Oberstein <>
To: Takeshi Yoshino <>
Date: Mon, 27 May 2013 04:59:09 -0700
Thread-Topic: [hybi] Call for interest: multiplexing dedicated for WebSocket
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Subject: Re: [hybi] Call for interest: multiplexing dedicated for WebSocket
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>>However, when running _different_ apps on the same device connecting to the same origin,

>You meant same ws:// address?
Yes, sorry not origin.

I had a look into the MUX RFC again .. couldn't find anser to the following (may have missed sth):

What WS addresses would be eligible to be multiplexed over a single WS connection?

a) ws://
b) ws://
c) ws://

d) wss://
e) wss://
f) wss://

All of a) - f) are to the same target IP:port and hence could share the same TCP.

However, d) - f) use wss, and hence have a TLS handshake right after TCP establishment.

So d) - f) cannot be multiplexed over the same physical WS as a) - c)?

Or can an implementation just "silently" transport a)-c) also over wss, and hence multiplex all of a) - f) over 1 physical WS?

Lastly, a)-c) are to the same target IP:port and also WS schema (ws, not wss) - and hence can be multiplexed over 1 physical WS even though they are to different URL paths?

IOW: in the context of ws-mux, what is "same target"?

The combination of IP, port and WS schema (but not necessarily same URL path)?

>>Btw: assuming SPDY runs over TLS exclusively, is there any need for WS frame masking anymore?

>See this post by Eric about BEAST attack. I think it's not easy to conclude that mask is unncessary for wss.
Ok, I see. Non-trivial.