ISO/IEC8802-2:1998 and 802.2,1998 Information technology—Telecommunications and information exchange between systems—Local and metropolitan area networks—Specific requirements—Part 2: Logical Link Control -Description
Abstract: This standard is part of a family of standards for local area networks (LANs) and metropolitan area networks (MANs) that deals with the physical and data link layers as defined by the ISO Open Systems Interconnection Basic Reference Model. The functions, features, protocol, and services of the Logical Link Control (LLC) sublayer, which constitutes the top sublayer in the data link layer of the ISO/IEC 8802 LAN protocol, are described. The services required of, or by, the LLC sublayer at the logical interfaces with the network layer, the medium access control (MAC) sublayer, and the LLC sublayer management function are specified. The protocol data unit (PDU) structure for data communication systems is defined using bit-oriented procedures, as are three types of operation for data communication between service access points. In the first type of operation, PDUs are exchanged between LLCs without the need for the establishment of a data link connection. In the second type of operation, a data link connection is established between two LLCs prior to any exchange of information-bearing PDUs. In the third type of operation, PDUs are exchanged between LLCs without the need for the establishment of a data link connection, but stations are permitted to both send data and request the return of data simultaneously.
Keywords: local area networks, protocols, logical link control
Content
1. Overview
1.1 Scope and purpose
1.2 Standards compatibility
1.3 Normative references
1.4 Acronyms and definitions
1.4.1 Acronyms and abbreviations
1.4.2 Definitions
1.4.3 Basic reference model
1.4.4 Management framework
1.4.5 Systems management overview
1.4.6 Common management information service definition
1.4.7 Information model
1.4.8 Guidelines for the definition of managed objects
1.5 Conformance
1.5.1 Static conformance
1.5.2 Dynamic conformance
1.5.3 PICS proforma
2. LLC sublayer service specifications
2.1 General
2.2 Network layer/LLC sublayer interface service specification
2.2.1 Overview of interactions
2.2.2 Detailed service specifications
2.3 LLC sublayer/MAC sublayer interface service specification
2.3.1 Overview of interactions
2.3.2 Detailed service specification
2.4 LLC sublayer/LLC sublayer management function interface service specification
3. LLC PDU structure
3.1 General
3.2 LLC PDU format
3.3 Elements of the LLC PDU
3.3.1 Address fields
3.3.2 Control field
3.3.3 Information field
3.3.4 Invalid LLC PDU
4. LLC types and classes of procedures
4.1 General
4.2 Classes of LLC (conformance clause)
4.2.1 Class I LLC
4.2.2 Class II LLC
4.2.3 Class III LLC
4.2.4 Class IV LLC
4.3 Support of route determination entity (RDE) (conformance clause)
5. LLC elements of procedure
5.1 General
5.2 Control field formats
5.2.1 Information transfer format—I
5.2.2 Supervisory format—S
5.2.3 Unnumbered format—U
5.3 Control field parameters
5.3.1 Type 1 operation parameters
5.3.2 Type 2 operation parameters
5.3.3 Type 3 operation parameters
5.4 Commands and responses
5.4.1 Type 1 operation commands and responses
5.4.2 Type 2 operation commands and responses
5.4.3 Type 3 operation commands and responses
6. LLC description of the Type 1 procedures
6.1 Mode of operation
6.2 Procedure for addressing
6.3 Procedure for the use of the P/F bit
6.4 Procedures for logical data link setup and disconnection
6.5 Procedures for information transfer
6.5.1 Sending UI PDUs
6.5.2 Receiving UI PDUs
6.6 Uses of the XID command PDU and response PDU
6.7 Uses of the TEST command PDU and response PDU
6.8 List of logical data link parameters
6.8.1 Maximum number of octets in a UI PDU
6.8.2 Minimum number of octets in a PDU
6.9 Precise description of the Type 1 procedures
6.9.1 LLC precise specification
6.9.2 Station component overview
6.9.3 Service access point (SAP) component overview
7. LLC description of the Type 2 procedures
7.1 Modes
7.1.1 Operational mode
7.1.2 Non-operational mode
7.2 Procedure for addressing
7.3 Procedures for the use of the P/F bit
7.4 Procedures for data link setup and disconnection
7.4.1 Data link connection phase
7.4.2 Information transfer phase
7.4.3 Data link disconnection phase
7.4.4 Data link disconnected phase
7.4.5 Contention of unnumbered mode setting command PDUs
7.5 Procedures for information transfer
7.5.1 Sending I PDUs
7.5.2 Receiving an I PDU
7.5.3 Reception of incorrect PDUs
7.5.4 Reception of out-of-sequence PDUs
7.5.5 Receiving acknowledgment
7.5.6 Receiving an REJ PDU
7.5.7 Receiving an RNR PDU
7.5.8 LLC busy condition
7.5.9 Waiting acknowledgment
7.5.10 Reception of duplicate I PDUs
7.6 Procedures for resetting
7.7 FRMR exception conditions
7.8 List of data link connection parameters
7.8.1 Timer functions
7.8.2 Maximum number of transmissions, N2
7.8.3 Maximum number of octets in an I PDU, N1
7.8.4 Transmit window size, k
7.8.5 Minimum number of octets in a PDU
7.8.6 Receive window size, RW
7.9 Precise description the Type 2 procedures
7.9.1 General
7.9.2 Connection service component overview
8. LLC description of the Type 3 procedures
8.1 Modes of operation
8.2 Procedure for addressing
8.3 Procedure for the use of the P/F bit
8.4 Procedures for link setup and disconnection
8.4.1 Sequence number resynchronization
8.4.2 Destruction of a transmit sequence state variable, V(SI)
8.4.3 Destruction of a receive sequence state variable V(RI) and reception status state variable V(RB)
8.5 Procedures for information transfer
8.5.1 Sending ACn command PDUs
8.5.2 Receiving ACn command PDUs
8.5.3 Sending ACn response PDUs
8.5.4 Receiving acknowledgment
8.6 List of logical link parameters
8.6.1 Maximum number of transmissions, N4
8.6.2 Maximum number of octets in an ACn command PDU, N3
8.6.3 Minimum number of octets in a PDU
8.6.4 Acknowledgment time, T1
8.6.5 Receive lifetime variable, T2
8.6.6 Transmit lifetime variables, T3
8.7 Precise description of Type 3 procedures
8.7.1 Type 3 receiver component
8.7.2 Type 3 sender component
9. LLC RDE procedures
9.1 Overview of RDE
9.1.1 Overview of source routing and route determination
9.1.2 RDE system structure
9.2 Support of the LLC service
9.2.1 Service to the LLC
9.2.2 Preservation of the LLC service
9.2.3 Quality of service
9.2.4 Internal sublayer service within the LLC
9.3 Principles of operation
9.3.1 Route control operation
9.3.2 Station architecture
9.3.3 Model of operation
9.3.4 PDU transmission
9.3.5 PDU reception
9.3.6 The learning process
9.3.7 The protocol
9.4 Encoding of RDE PDUs
9.4.1 Route query command (RQC)
9.4.2 Route query response (RQR)
9.4.3 Route selected command (RSC)
9.5 Encoding of the routing information field (RIF)
9.6 RDE route control process
9.6.1 Route control operating parameters
9.6.2 Route determination parameters
9.6.3 Precise description of route control procedures
10. The route determination component (RDC)
10.1 The route determination operating parameters
10.2 Precise description of route determination procedures
