Overview - ISO/IEC 15899:1998 (Broadband connection oriented bearer services)
ISO/IEC 15899:1998 specifies the service description and control aspects of broadband connection‑oriented bearer services for Broadband Private Integrated Services Networks (B‑PISNs). It defines how users negotiate traffic contracts and request ATM virtual‑channel connections (point‑to‑point and point‑to‑multipoint) to carry unrestricted digital information. The standard focuses on control and signalling requirements; change of traffic characteristics during a call and charging are explicitly outside its scope.
Key topics and technical requirements
- Service categories: Defines bearer types mapped to ATM service categories - CBR (Constant Bit Rate), rt‑VBR (Real‑Time VBR), nrt‑VBR (Non‑Real‑Time VBR), ABR (Available Bit Rate) and UBR (Unspecified Bit Rate).
- Traffic parameters: Specifies attributes per direction such as PCR (Peak Cell Rate), SCR (Sustainable Cell Rate), MBS (Maximum Burst Size), MCR (Minimum Cell Rate), best‑effort indication, CLP/CLR, and optional CDV (Cell Delay Variation) and end‑to‑end delay.
- Access and protocols: Access channel is the ATM virtual channel; normative protocol references include ATM layer (ITU‑T I.361) and ATM Adaptation Layer (I.363). Higher‑layer behaviour is application specific.
- Quality of Service (QoS): Defines QoS classes (QoS class 0 and network‑specific classes) and allows optional specification of CLR/CDV/delay for service assurance.
- Service attributes and constraints: Lists allowable bearer classes (BCOB‑A, BCOB‑C, BCOB‑X), symmetry, communication configurations, tagging and frame discard options.
- Conformance: Protocol standards claiming conformance must specify signalling and equipment behaviour sufficient to support the service aspects relevant to the interface or equipment.
- Interworking: Notes interworking considerations with public B‑ISDN and narrowband PISN (N‑PISN); interoperable with ATM Forum UNI/TM specs.
Practical applications and users
- Network architects and engineers designing private ATM/B‑PISN infrastructures.
- Telecom equipment vendors implementing ATM interfaces, AAL, and UNI functionality.
- Protocol designers and implementers developing signalling for connection‑oriented broadband bearer services.
- Enterprise IT/network teams planning dedicated broadband private networks requiring explicit QoS and traffic contracts.
- Standardization bodies and test labs validating interoperability with public B‑ISDN and ATM Forum UNI/TM specifications.
Related standards (normative references)
ISO/IEC 15899:1998 is a pragmatic specification for implementing and controlling ATM‑based bearer services in private broadband networks, useful whenever precise traffic contracts, QoS classes, and ATM‑level signalling are required.