Table of Contents
1Scope
2Normativereferences
2.1IdenticalRecommendations/InternationalStandards
2.2Additionalreferences
3Abbreviations
4DefinitionsandConcepts
4.1BasicReferenceModelConcepts
4.2Additionaldefinitionsandconcepts
5Overview
5.1General
5.2Interworkingandencapsulation
6Principlesofprotocolidentification
6.1Needforprotocolidentification
6.2Protocolidentifierregistriesandvalues
6.3Protocolidentificationmethods
6.4Protocolidentifiers
7Principlesofprotocolencapsulation
7.1Encapsulationfunction
7.2Protocolencapsulationmethods
7.3RelationshipsamongEFs,EdPs,andEgPs
AnnexA-CurrentRecommendations/InternationalStandards
SupportingPIEPrinciples
AnnexB-Examplesofprotocolidentificationand
encapsulationmethods Abstract
In a layered approach to protocol architecture, protocols have a relationship to one another such that a protocol at layer (n) used the services of the layer below it - the (n-1) services - which - in turn, are provided by a layer (n-1) protocol. Of the services used by a layer (n) protocol, one is the encapsulation of its (n) Protocol Data Units (PDUs) in a way which is transparent to it. This encapsulation is realized by the carriage of the (n) PDUs as user data in an (n-1) Service Data Unit (SDU).
