For Identifiers (just the complete URI and local part, not about mechanisms)

permanent #permanent

permanently resolve to a digital object #permanently resolve to a digital object

unique within our PID system without the DNS name portion of the #unique within our PID system without the DNS name portion of the

URL #URL

works with VIVO, arXiv, OAIS (CUL), Voyager Catalog, and WorldCat etc. #works with existing systems

resolvable through a web browser #resolvable through a web browser

Simplicity #Simplicity

support for a local namespace prefix and an identifier part #support for a local namespace prefix and an identifier part

support for opaque identifiers #support for opaque identifiers

Local part should not be Cornell branded #Local part should not be Cornell branded

may be surrogate for physical object #may be surrogate for physical object

should be short (so use 26 letters plus numbers) #should be short

should be easy to copy by hand #should be easy to copy by hand

For Resolver and System

Supports billions of identifiers #Supports billions of identifiers

Robust architecture #Robust architecture

Robust implementation #Robust implementation

ability to request metadata about the identifier #ability to request metadata about the identifier

lightweight understanding of identifier equivalence #lightweight understanding of identifier equivalence

should be easily discoverable by Google #should be easily discoverable by Google

integrate well with the "web architecture" #integrate well with the web architecture

vitality checking #vitality checking

Need to avoid unbounded generation of surrogate persistent identifiers #Need to avoid unbounded generation of surrogate persistent identifiers

PID corresponding to every Cornell NetID #PID corresponding to every Cornell NetID

useful error when check digit is wrong #useful error when check digit is wrong

Governance Issues

Requires payment to external organization #Requires payment to external organization

Can continue resolve IDs in absence of external organization #Can continue resolve IDs in absence of external organization