1. Digital Object Interface Protocol (DOIP)
19 Mar 2018
Larry Lannom
Corporation for National Research Initiatives

2. High-Level View of Digital Object Infrastructure
ID: 843… G
(object:publication)
DOIP
Identifier Service
Identifier Service
DOIP
ID: 987/…
DOIP
Repo/Registry
Repo/Registry
Repo/Registry
Identifier Service
DOIP
Repo/Registry
Repo/Registry
(object:dataset)
DOIP
ID: 123…
ID: 876… A
ID: XZY…
ID: HGY…
(object:collection)
End users, developers, and automated processes
deal with persistently identified, virtually aggregated digital
objects, including collections
which are overlays on multiple network services
which in turn are
overlays on existing or future information
storage systems.

3. DOIP: Why Do We Need This?
Full realization of a Digital Object level of abstraction requires a common protocol
Basic access to and operations on an object should not vary according to current environment
Portability of objects is not sufficient – moving an object from one repository to another should not change its behavior
Changing the underlying technology for a repository should not change the behavior of an object
Common protocol will drive normalization of common DO attributes and behavior
Network effect - DOs that respond to the protocol will drive protocol adoption
Network effect – Spread of the protocol will drive the creation of compliant objects
Use Cases
Interacting with repositories, which are themselves DOs
Create, Retrieve, Update, Delete, List
DOs as compute engines, service providers
Routing DOs in a workflow
Query for attributes
Write state data into the DO as needed

4. DOIP Implementation Additional implementations more than welcome
CNRI current implementation embedded in Cordra v1
Cordra v2 in beta (running across three different projects)
HTTP/JSON
Protocol buffers (release version TBD)
bits on the wire (TBD)
Additional implementations more than welcome
Basic elements
CallerID: The identifier of the entity requesting invocation of the operation
ObjectID: The identifier of the object to be operated upon
OperationID: The identifier that specifies the operation to be performed
Input: A stream of bytes that contains the input to the operation, including any parameters, or content
Output: A stream of bytes that contains the output of the operation, including any content or messages.
Assumes Types, PIDs

5. DOIP: A Brief History
Managing Access to Digital Information: An Approach Based on Digital Objects and Stated Operations - The Cross-Industry Working Team (XIWT), May 1997
“By delineating specific types of operations that may he performed on digital objects – that is, stated operations – a basis may emerge for orderly management of rights associated with digital objects and their contents
Digital Object Protocol Specification: Version: 1.0 November 12, 2009
“...the protocol and authentication mechanism used to interact with digital objects through a connection to a digital object server. Each interaction consists of a caller invoking or applying an operation on a digital object. The server, caller, each operation, and the object itself are all uniquely identified using Handle Identifiers.”
Framework for discovery of identity management information - ITU-T x.1255, (note: DE = DO)
“Each interaction with an instance of a DE consists of invoking or applying an operation on the DE.”