- From: Sergey Beryozkin <sberyozkin@zandar.com>
- Date: Tue, 16 Sep 2003 22:18:36 +0100
- To: "Mark Baker" <distobj@acm.org>
- Cc: <www-archive@w3.org>
Hi Mark, You said in an earlier mail : Just that if it's not late bound, then client software needs upgrading whenever new services are introduced. The opposite isn't true, however; just because you are late bound, it doesn't mean you don't need client upgrades to access new services. Consider an FTP client that supports ftp URIs; when a new scheme is introduced, it needs upgrading to be able to use it. It's really the combination of the uniform interface and late-binding which is why the Web is so powerful; HTTP clients can interact with *ANY* URI (perhaps with a proxy), because HTTP semantics are uniform to *ALL* URI. Thanks for the explanation. I think I can see now how late-binding helps HTTP clients, especially after seeing what a proxy can do. This is how I see what a late-binding can do for a client : For example, if a document of known mime-type is fetched for the purposes of presentation, then it doesn't matter which scheme, http:// or custom://, was used, and yes, a presentation software (a browser in a simple case) doesn't need to get upgraded. But if a document is of unknown mime type, then a presentation software will have to be upgraded. In other words, with late-binding, it's a layer which communicates with a service(s) doesn't need to get upgraded, while an application layer may or may not need to get updated. The same probably applies to a RESTful (SOAP or XML) client which enables a machine to machine communication. For example, if a new service is available, then as far as a SOAP client stack (which wraps/unwraps XML doc in/out of envelope, etc, sends and receives it) is concerned it doesn't need to get changed. An application layer may not need to change as well, provided the data returned is of known format or if those data can be transformed into a known format by some generic pre-processing filter. Otherwise, to avail of a new service's data, the application layer will have to get changed as well. So, late-binding does indeed reduce integration costs for a client in that a layer talking to (URI-)identified resources through a uniform interface doesn't need to get changed. This is of critical importance to the Web in general. It seems that it would also be beneficial for a SOAP client as well, though it's probably of less critical importance than it's for a general HTTP client. Do you agree ? Thanks ! Sergey Beryozkin
Received on Wednesday, 17 September 2003 05:45:44 UTC