[March 14, 2001] Version 2.0 of IPDR.org's specification 'Network Data Management - Usage' uses W3C XML Schema and SOAP.
About IPDR.org: The purpose of the organization is "(1) To develop, agree upon and publish a non-proprietary, open specification for the representation and encapsulation of Internet Protocol (IP)-based events for use by business, operations and decision support systems. Such events include, but are not limited to, IP-based network services, application services and e-commerce transactions; (2) To develop, agree upon and publish a non-proprietary, open specification for the representation and encapsulation of IP-based network and service elements provisioning events; (3) To promote work accomplished and uniform specifications to the industry and submit approved published specifications to the appropriate standards bodies for acceptance in the public domain."
About the version 2.0 NDM-U specification:
This document is intended to specify technical information that is sufficient for practical implementations of interchange of usage data among service elements participating in the delivery of IP-based services, either within a single enterprise or across multiple enterprises. The IPDR organization intends to submit this specification to selected accredited organizations for consideration as an approved standard.
Abstract: "In order to develop the IPDR record format it is required that a framework be in place that formally classifies the 'IP network and service elements' and 'support systems.' Next, the relationship between such subsystems needs to be in place to determine the flow of information between components. Finally, the requirements of each subsystem must be determined in order to specify the type of 'IP resource and service usage information' that will be exchanged. This document proposes a reference model to satisfy the above requirements. Chapter 2 proposes a general IP support system framework. This Chapter is intended to identify key components found in production IP networks, present the relationship between them, and define basic terminology. The Chapter focuses on the network and service element layer (NSE), and illustrates the concepts with example ISP network infrastructures. Chapter 3 details the business requirements that the structures and systems defined in Chapter 2 must satisfy. Next, Chapter 4 describes the information flow requirements between the NSE layer and the various support systems identified. Chapter 5 concludes with a proposed structure of the IPDR record for various IP-based services, and motivates this structure using the business requirements identified in Chapter 3 and the technical requirements identified in Chapter 4. Chapter 6 is the template for documenting service requirements definitions in Chapter 3."
The specification is divided into four major chapters: (1) IPDR Reference Model - a definition of the abstract and operational relationships between entities involved in the generation, recording, storage, transport, and processing of usage attributes. (2) Business Requirements - a definition of business requirements to be addressed by the protocol specification and specific scenarios for the major process flows anticipated in actual application. (3) Protocol - the notation, data unit syntax, and dynamic procedures involved in the operation of the interfaces specified in the reference model. (4) Structures - the specific usage and document attributes and collections of such attributes associated with services for which accounting occurs."
"The 2.0 revision introduces a major upgrade of the syntax notation of the protocol, namely XML Schema versus XML 1.0. This upgrade has been introduced to allow the protocol to specify strong typing of the usage attributes, thus conforming to the business requirements for data integrity. In addition, the dynamic operation of IDPR document transport has been specified, using the consensus choice for best conforming to business requirements, Simple Object Access Protocol (SOAP). Finally, the usage attributes for each of the services defined in the Business Requirements chapter are now formally specified, using the XML Schema definition supplied in the Protocol chapter."
IPDR and SOAP Mapping Specifics: Section 4.3 "specifies an IPDR usage document transfer protocol corresponding to the 'D-interface' outlined in the basic IPDR network model. The Simple Object Access Protocol (SOAP) 1.1 is specified as the underlying transport mechanism for performing these transfers. SOAP was chosen in the interest of utilizing emerging standards rather than recreating existing work. In particular, SOAP specifies a means to map an XML based transfer protocol on top of HTTP. HTTP is attractive because of its ubiquity, affinity to XML (perhaps more emotional than technical) and its ability to easily traverse firewalls. The SOAP specification is more than a mapping of XML documents to HTTP. SOAP is intended as an alternative means for remote procedure invocations similar to those offered by COM, CORBA or RMI, but with XML based serializations. The use of SOAP by IPDR utilizes the concept of remote procedures, but one of the parameters in an IPDR exchange is the IPDR document itself. Unfortunately, the base SOAP specification focuses on the transmission of basic data types such as integers, floats and strings, but not intact XML documents. Therefore, this convention is currently defined by IPDR..."
The IPDR organization has adopted the Telecommunication Management Forum's (TMF) telecommunications operation map (TOM) for the purposes of motivating the functional role and interfaces of the IPDR specifications relative to operations support systems (OSS). We have chosen the TOM because it is a well-known, industry-accepted organizational model of telecommunications support systems used by carriers and service providers today. The TMF Model is useful as a model of typical systems, and as motivation for design decisions. However, the TMF Model itself is not part of IPDR, and the data structures and interfaces of IPDR may be used in systems that vary substantially from the TMF Model.
From the Version 2.5 NDM-U draft: "This document, in conjunction with the referenced Service Definition documents, is intended to specify technical information that is sufficient for practical implementations of interchange of usage data among service elements participating in the delivery of IP-based services, either within a single enterprise or across multiple enterprises. The IPDR organization intends to submit this specification to selected accredited organizations for consideration as an approved standard. This specification is divided into three major chapters: (1) IPDR Reference Model - a definition of the abstract and operational relationships between entities involved in the generation, recording, storage, transport, and processing of usage attributes. (2) Business Requirements - a definition of business requirements to be addressed by the protocol specification and specific scenarios for the major process flows anticipated in actual application. (3) Protocol - the notation, data unit syntax, and dynamic procedures involved in the operation of the interfaces specified in the reference model. The Protocol chapter represents the specific design produced through analysis of the Business Requirements chapter, consistent with the Reference Model chapter. Performance and Implementation Considerations: The Protocol Working Group's charter for the 2.5 document was initially focused on identifying the performance implications of an XML/SOAP/HTTP exchange of usage information. During this time vendors began examining and implementing the NDM -U 2.0 Protocol. While performance results were slow to come by, implementation questions arose very quickly. The 2.5 Protocol addresses a number of implementation related issues identified with the 2.0 protocol. Concern continues to be raised by members regarding the compactness and efficiency of an XML oriented protocol. XML has the desirable property of being human readable, which can make the analysis or even modification of usage documents available through a simple XML editor. Validation mechanisms also exist to identify syntactically correct documents. However, an uncompressed XML message carrying a mixture of numeric and string values may be four to ten times the size of an equivalent 'socket based' protocol. The computational load for the large number of string comparisons implied by XML also brings into question its use in 'high volume, low value' events. Actual data to quantify the performance offset between NDM-U over SOAP and a binary transfer mechanism has not been put forward yet..."
References:
Announcement: "IPDR.org Members to Demonstrate Implementation of NDM-U 2.0 Specification. ACE*COMM, Info Directions and Virtual Summit Align to Highlight Specification's Effectiveness for Service Providers."
Network Data Management Usage (NDM-U) For IP-Based Services. Version 2.0 105 pages. [cache]
[June 22, 2001] Network Data Management - Usage (NDM-U) For IP-Based Services. Version 2.5. April 12, 2001. 62 pages. Chief Editor: Steve Cotton (Cotton Management Consulting). See also the [extracted] XML schema, perhaps also online as a separate document.
