- From: Mark Baker <distobj@acm.org>
- Date: Mon, 9 Jun 2008 14:32:38 -0400
- To: "Drummond Reed" <drummond.reed@cordance.net>
- Cc: www-tag@w3.org
Hi Drummond, On Mon, Jun 9, 2008 at 12:07 PM, Drummond Reed <drummond.reed@cordance.net> wrote: > Mark, > > Of course you are right, any URI is an identifier, and can be used to > identify a resource regardless of protocol or interaction method. However > URIs whose schemes are protocols or interaction methods (e.g., http:, > https:, ftp:, mailto:) tend to create confusion if either: a) the resource > is completely abstract and thus not available over that protocol, or b) the > resource is accessed over other protocols. I agree that sometimes confusion results, but that's a brain problem. I've yet to see it cause an interoperability problem 8-) > Of particular concern is how you establish synonymity of identifiers across > multiple protocols (i.e., prove the identifiers identify the same target > resource) if the identifier indicates a specific protocol. Here's a > practical example: as explained in [1], the editors of OpenID Authentication > 2.0 [2] found that, as much as they wanted to, they could not specify that > http: and https: URIs that were equivalent in all respects except the scheme > identified the same resource. So the OpenID Authentication 2.0 spec requires > OpenID relying parties to default partially-typed OpenID URLs (e.g., > user.openidprovider.com or opidprovider.com/user) to http: URIs. This means > OpenID users who want the higher security of using an https: URI (as > recommended by the spec) must type the entire string beginning with > "https:", which is widely acknowledged as a usability issue. The OpenID editors were right not to make assumptions about http and https URI equivalence. But couldn't the http/https synonym problem be solved by a publisher establishing a redirect from an http URI to an https URI? > In addition, a > reassignable XRI i-name that is easy for an OpenID user to remember and type > is automatically mapped to a persistent canonical XRI i-number in the > resulting XRDS document, thereby protecting the user from OpenID recycling > (another serious security issue also explained in more detail in [1]). Interesting. I haven't looked at that, but will do so. > Hope this helps, Yes, thanks. Mark.
Received on Monday, 9 June 2008 18:33:20 UTC