Protocol questions

[Aaron Stone]

On Thu, 2008-02-28 at 14:36 +0100, Roy Lyseng wrote:
> Hi,
> 
> I have a question around the protocol support in memcached:
> 
> Is there any (good) reason for registering one port per protocol in 
> memcached? We have the text protocol, the binary protocol, and yet other 
> protocols are in the coming. Would it be better to listen on a single 
> port per IP protocol (TCP or UDP) and dispatch subprotocol requests 
> internally? We could e.g. let the first byte in a packet determine the 
> subprotocol (text protocol reserves all lower-case ASCII letters...) and 
> then dispatch the socket to the proper subprotocol handler.
> 
> I am afraid of the myriad of options that will be needed to configure a 
> memcached server. It would be great if we only need one option per IP 
> protocol. Besides, it will make it easier for us if we decide to 
> register official IANA ports for memcached.
> 
> Roy

+1 for keeping things on the same port because we have a magic byte to
differentiate protocols and to know when our server doesn't understand
the client's version, too!

+1/2 on the IANA point. I think that the most important issue is that we
don't appear to be setting ourselves up to request one port number per
protocol _version_. The text and binary protocols aren't so much
different versions as they are different protocols entirely.

Aaron