next up previous
Next: Description of RCDS Up: Introduction Previous: Design Goals

Issues

The following issues must be considered:

The assumed significance of transition issues on the success of the project influenced our design in the following ways: (a) we allow ordinary URLs as one kind of resource name, (b) we use existing file servers and file access protocols, and (c) we employ DNS as a component of the system rather than building a new distributed database from the ground up.

The need for reliable authentication and integrity assurances, coupled with the difficulty of providing secure servers, prompted us to use end-to-end (between information provider and user) authentication, consisting of public-key signatures and cryptographically signed certificates, rather than depending on the security of resource catalog servers or file servers (though reasonable security for these is still required to thwart denial-of-service attacks).

We have implemented a flexible consistency model which combines a convergence based peer update protocol for resource locations with a stricter token-based protocol for catalog information.

Finally, some of the inherent limitations of DNS and the desire to separate administration of ``naming authority'' names from administration of resource names for a particular naming authority, led us to use DNS only as a means to identify one or more resource catalog servers for a particular resource naming authority, rather than to provide resource location or catalog information directly through DNS.


next up previous
Next: Description of RCDS Up: Introduction Previous: Design Goals

Keith Moore
Fri Feb 7 11:53:58 EST 1997