Re: [hybi] [Uri-review] ws: and wss: schemes

[Jamie Lokier <[e-mail]>]

Křištof Želechovski wrote:
> I think the idea to use Web Sockets on the server is void; the server can
> use TCP/IP at will.

Nice theory.  I believe you have correctly described the intentions of
the WebSockets protocol proposers (as I understand them), and that the
theory is denying reality.

It's wrong.  A server cannot use TCP/IP at will in two scenarios:

1. A server must use WebSockets if it's accessing services which a
   different provider has only made available via WebSockets, due to
   the provider only intending the service for web browsers.

   For example, at one time something like Google Maps' image back-end
   would fit this pattern: only intended for one web application, but
   actually used by various third parties because it's useful.

   Judging by the modern trend to 'mashups', expect this practice to
   become widespread

2. When a service is provided by WebSockets to support a web browser,
   and a requirement emerges to provide the same service to other programs.

   Many implementors will use the path of least resistance, which is
   to continue offering using the service over WebSockets in the new
   context, and require the clients to use generic non-browser
   WebSockets code.  That is simpler than specifying and implementing
   a second protocol for the same service.

   For examples of where this has happened before, see SOAP.  It runs
   over HTTP simply to reuse deployed and well understood code and
   infrastructure.  In principle it could run over raw TCP/IP or a
   simple framing protocol, but that's not done in practice.

   Expect the same to occur with WebSockets if it is widely used by web
   applications.  If only because of familiarity and duplication avoidance.

-- Jamie