|Open Group Technical Standard|
|Data Link Provider Interface (DLPI), Version 2|
|Document Number: C811|
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The DLPI standard specifies a STREAMS kernel-level instantiation of the ISO Data Link Service Definition ISO/IEC 8886 and Logical Link Control ISO/IEC 8802-2 (LLC). Where the two standards do not conform, ISO/IEC 8886 prevails.
The DLPI enables a data link service user to access and use any of a variety of conforming data link service providers, without requiring special knowledge of the provider's protocol.
Specifically, the interface is intended to support X.25 LAPB, BX.25 level 2, SDL C, ISDN LAPD, Ethernet, CSMA/CD, FDDI, token ring, token bus, Bisync, Frame Relay, Native ATM Services (see Referenced Documents), Fiber Channel and HIPPI. Readers should note that the list of data links supported by the interface may be augmented and is published on the World-Wide Web at http://www.opengroup.org/public/pubs/catalog/u019, which is DLPI Corrigendum U019. (see under Ordering Information). This Corrigendum will periodically be updated to add relevant information such as recognised implementors' agreements/guidelines for common data link providers.
Among the expected data link service users are implementations of the OSI network layer and SNA path control.
The interface specifies access to data link service providers, and does not define a specific protocol implementation. Thus, issues of network management, protocol performance, and performance analysis tools are beyond the scope of this document and should be addressed by specific implementations of a data link provider. However, accompanying each provider implementation should be information that describes the protocol-specific behavior of that provider. Currently, there are plans to come up with a set of implementors' agreements/guidelines for common data link providers. These agreements will address issues such as DLSAP address space, subsequent addresses, ppa access and control, QOS, supported services etc.
A Glossary and Index are also provided.
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