ABOUT THE BOOK

Formats

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Formats

edition; it applies until otherwise indicated in a new edition. Consult Part 3 of the latest edition of IBM System/370, 30xx. and 4300 Processors - Bibliography, GC20-0001, for current information on this com- munication architecture. For a summary of the changes in this book, see "Summary of Changes."

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© Copyright International Business Machines Corporation 1977, 1989 All Rights Reserved

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iii

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ABOUT THE BOOK

This book describes the Systems Network Architecture (SNA) formats used between subarea nodes and peripheral nodes, and between type 2.1 nodes using peer-to-peer protocols.

HOW THIS BOOK IS ORGANIZED

This book identifies the formats and meanings of the bytes that a basic link unit (BLU) contains. A BLU is the basic unit of transmission at the data link and link station level. Figure 1-1 on page vii illustrates the organization of this book.

Chapter 1 identifies the formats and meanings of the bytes in a link header and a link trailer.

Chapter 2 identifies the formats and meanings of the information-field bytes in an SOLC and System/370 OLC Exchange Identification (XIO) command and response.

Chapter 3 identifies the formats and meanings of the bytes in a transmission header.

Chapter 4 identifies the formats and meanings of the bytes in a request or response header.

Chapter 5 identifies the formats and meanings of the bytes in request units and response units.

Chapter 6 explains the transmission services and function management profiles that SNA defines to describe session characteristics.

Chapter 7 identifies the formats and meanings of the bytes in user-structured subfields that appear in a request or response unit.

Chapter 8 identifies the formats and meanings of the control vectors, session keys, and management services vectors that appear in a request or response unit.

Chapter 9 explains the meanings of the sense data defined by System Network Architecture (SNA) that appear, for example, in negative response units.

Chapter 10 presents the descriptions and formats of the different function man- agement headers.

Chapter 11 identifies the formats and meanings of the bytes in a presentation serVices header.

Chapter 12 identifies the formats and meanings of the general data stream (GOS) variables that are specific to SNA service transaction programs.

Chapter 14 identifies the general data stream (GOS) variables that are for general use.

Chapter 15 identifies the formats and meanings of the message units that SNA/File Services transaction programs use.

Appendix A provides a summary of SNA character sets and symbol-string types.

Appendix B provides a summary of general data stream identifier (GOS 10) value assignments.

Appendix C lists the abbreviations and symbols that are used in this book.

RELATED PUBLICATIONS

vi

SNA Formats

Related publications, providing overview and protocol information, are:

• Systems Network Architecture Concepts and Products (GC30-3072)

• Systems Network Architecture Technical Overview (GC30-3073)

• IBM Synchronous Data Link Control Concepts (GA27-3093)

• Systems Network Architecture Format and Protocol Reference Manual:

Architectural Logic (SC30-3112)

• Systems Network Architecture Type 2.1 Node Reference (SC30-3422)

• Systems Network Architecture: Sessions Between Logical Units (GC20-1868)

• Systems Network Architecture: Transaction Programmer's Reference Manual for LU Type 6.2 (GC30-3084)

• Systems Network Architecture Format and Protocol Reference Manual:

Architecture LogiC for LU Type 6.2 (SC30-3269)

• Systems Network Architecture LU 6.2 Reference: Peer Protocols (SC30-6808)

• Systems Network Architecture/Distribution Services Reference (SC30-3098)

• Systems Network Architecture/File Services Reference (SC31-6807)

• Systems Network Architecture/Management Services Reference (SC30-3346)

• Token-Ring Network Architecture Reference (SC30-3374)

• Document Interchange Architecture: Technical Reference (SC23-0781)

• IBM Implementation of X.21 Interface General Information Manual (GA27-3287)

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Chapter 1

Chapter 2

Chapter 3

Chapter 4

Chapter 5

Chapter 6

Chapter 7 Chapter 8

Chapter 9 Chapter 10 Chapter 11 Chapter 12 Chapter 13 Chapter 14 Chapter 15

I LH I Inla,matlan Field

~

RU

' -

T

I

^{RHI RU}

...

~ T

(Response) RU

... ..,J

1 ~

Negative Positive

Response Response

TS Profiles FM Profiles

Control Vectors

Sense Data

LH = Link Header LT = Link Trailer

XID = Exchange Identification TH = Transmission Header RH = Request/Response Header RU = Request/Response Unit TS = Transmission Services FM = Function Management MS = Management Services Figure 1-1. Organization of thi s Book

I LT I BLU

(SDLC)

PIU

~

BIU

..-'

•

(Request) RU

... ..,J

~ ~

SNA-Deflned End-User

Data Data

TS Profiles FM Profiles Structured Subfields Control Vectors

Session Keys MS Vectors FM Headers PS Headers SNASTPs SNA/DS (MU) GDS Variables

SNA/FS (MU)

PS = Presentation Services STP = Service Transaction Program SNA/DS = SNA/Distribution Services MU = Message Unit

GDS = General Data Stream BLU = Basic Link Unit PIU = Path Information Unit BIU = Basic Information Unit SNA/FS = SNA/File Services

vii

Additions for GA27·3136·10:

This edition includes information about:

• Network Asset Management

• Change Management

• Common Operations Services

• SNA/File Services

Changes from the previous edition:

• The style of presentation of the formats has been changed.

• An enhanced format set has been provided for SNAIDistribution Services

• Chapters 5.1 and 5.2 have been combined into Chapter 5.

Chapter 1. OLC Links . . . 1-1 Synchronous Data Link Control (SDLC) . . . 1-1 Link Header (Flag) . . . 1-1 Link Header (Address) . . . 1-2 Link Header (Control) . . . 1-3 Link Trailer (Frame Check Sequence) . . . 1-5 Link Trailer (Flag) . . . 1-7 Token-Ring Network DLC . . . . . . .. 1-7 Chapter 2. Exchange Identification (XID) Information Fields . . . 2-1 DLC XID Information-Field Formats . . . 2-1 Chapter 3. Transmission Headers (THs) . . . . . . .. 3-1 Introduction . . . 3-1 FID2 Layout . . . 3-1 FID2 Field Descriptions . . . 3-1 Chapter 4. Request/Response Headers (RHs) . . . 4-1 Introduction . . . 4-1 RH Formats . . . 4-4 IPR, IPM, and EXR . . . 4-8 ISOLATED PACING RESPONSE (IPR) . . . 4-9 ISOLATED PACING MESSAGE (IPM) . . . 4-9

"'-. EXCEPTION REQUEST (EXR) . . . 4-10

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Chapter 5. Request/Response Units (RUs) . . . 5-1 Introduction to Request Units . . . 5-1 Request Unit Summary Information . . . 5-2 Summary of Request RUs by Category . . . 5-2 Index of RUs by NS Headers and Request Codes . . . 5-2 Descriptions of Request Units . . . 5-4 ACTLU (ACTIVATE LOGICAL UNIT) . . . 5-4 ACTPU (ACTIVATE PHYSICAL UNIT) . . . 5-4 BID (BID) . . . 5-5 BIND (BIND SESSION) . . . 5-5 BIS (BRACKET INITIATION STOPPED) . . . 5-15 CANCEL (CANCEL) . . . 5-16 CHASE (CHASE) . . . 5-16 CLEAR (CLEAR) . . . 5-16 CRV (CRYPTOGRAPHY VERIFICATION) . . . '. . . .. 5-17 DACTLU (DEACTIVATE LOGICAL UNIT) . . . 5-17 DACTPU (DEACTIVATE PHYSICAL UNIT) . . . 5-18 INIT-SELF Format 0 (INITIATE-SELF) . . . 5-19 INIT -SELF Format 1 (INITIATE-SELF) . . . 5-21 LUSTAT (LOGICAL UNIT STATUS) . . . 5-22 NMVT (NETWORK MANAGEMENT VECTOR TRANSPORT) . . . 5-23 NOTIFY (NOTIFY) . . . 5-24 NOTIFY Vectors (Described O-origin) . . . 5-25 ILU/TLU Notification NOTIFY Vector . . . .. 5-25 LU-LU Session Services Capabilities NOTIFY Vector . . . 5-26 NSPE (NS PROCEDURE ERROR) . . . 5-27

RELQ (RELEASE QUIESCE) . . . 5-29 REQDISCONT (REQUEST DISCONTACT) . . . 5-30 REQMS (REQUEST MAINTENANCE STATISTICS) . . . 5-30 RQR (REQUEST RECOVERY) . . . 5-30 RSHUTD (REQUEST SHUTDOWN) . . . 5-31 RTR (READY TO RECEIVE) . . . 5-31 SBI (STOP BRACKET INITIATION) . . . 5-31 SDT (START DATA TRAFFIC) . . . 5-32 SHUTC (SHUTDOWN COMPLETE) . . . 5-32 SHUTD (SHUTDOWN) . . . 5-32 SIG (SIGNAL) . . . 5-33 STSN (SET AND TEST SEQUENCE NUMBERS) . . . 5-33 TERM-SELF Format 0 (TERMINATE-SELF) . . . 5-34 TERM-SELF Format 1(TERMINATE-SELF) . . . 5-35 UNBIND (UNBIND SESSION) . . . 5-37 Introduction to Response Units . . . 5-39 Positive Response Units with Extended Formats . . . 5-41 RSP(ACTLU) . . . 5-41 RSP(ACTPU) . . . 5-41 RSP(BIND) . . . 5-42 RSP(STSN) . . . 5-44 Chapter 6. Profiles . . . .

Introduction . . . . Transmission Services (TS) Profiles

TS Profile 1 . . . .

6-1 6-1 6-1 6-2 TS Profile 2 6-2

TS Profile 3 TS Profile 4 TS Profile 7

· . . . . . 6-2

· . . . . . 6-2 Function Management (FM) Profiles . . . .

FM Profile 0 . . . .

6-3 6-3 6-4 6-4 6-4 6-5 6-6 FM Profile 2

FM Profile 3 FM Profile 4 FM Profile 6 FM Profile 7 FM Profile 18 FM Profile 19

· . . . . . 6-6

Chapter 7. User Data Structured Subfields . . . . Introduction . . . . Descriptions . . . .

Unformatted Data Structured Data Subfield . . . . Session Qualifier Structured Data Subfield . . . . Mode Name Structured Data Subfield . . . . Session Instance Identifier Structured Data Subfield . . . . Network-Qualified PLU Network Name Structured Data Subfield . . . . Network-Qualified SLU Network Name Structured Data Subfield . . . . Random Data Structured Data Subfield . . . . Enciphered Data Structured Data Subfield

xii SNA Formats

6-6 6-7 7-1 7-1 7-2 7-2 7-2 7-2 7-3 7-3 7-4 7-4 7-5

Rules for Common Substructures Partitioning of Key/Type Values

Category-Dependent Keys Context-Sensitive Keys Parsing Rules . . . . Enclosing Rule for Substructures Control Vectors . . . .

Introduction

Control Vector Formats . . . . SSCP-LU Session Capabilities (XIOOI) Control Vector

LU-LU Session Services Capabilities (XIOCI) Control Vector Network Name (XIOEI) Control Vector . . . .

Prod u ct Set 10 (X I 10 I) Control Vector . . . . XID Negotiation Error (X 122 I) Control Vector COS/TPF (X I 2C I) Control Vector . . . . Mode (X 120 I) Control Vector . . . . Extended Sense Data (X 135 1) Control Vector Fully-qualified PCID (X 160 I) Control Vector . Session Key . . . .

Network Name Pair or Uninterpreted Nam~ Pair (X I06 1) Session Key URC (XIOAI) Session Key . . . . . . . . MS Major Vectors and Unique Subvectors

Introduction . . . . MS Major Vector Formats

Alert (X 10000 I) MS Major Vector Alert MS Subvectors . . . .

SDLC Link Station Data (X I 8CI) Alert MS Subvector . . . . Current N(S)/N(R) Counts (X 101 1) SDLC Link Station Data Subfield Outstanding Frame Count (X 1021) SDLC Link Station Data Subfield

Last SDLC Control Field Received (X 103 1) SDLC Link Station Data Subfield Last SDLC Control Field Sent (X I041) SDLC Link Station Data Subfield Sequence Number Modulus (X 105 1) SDLC Link Station Data Subfield . . . . Link Station State (X 106 1) SDLC Link Station Data Subfield . . . . LLC Reply Timer Expiration Count (X 107 1) SDLC Link Station Data Subfield Last Received N(R) Count (X 108 1) SDLC Link Station Data Subfield

Basic Alert (X 1911) Alert MS Subvector

Generic Alert Data (X 192 I) Alert MS Subvector Probable Causes (X 193 1) Alert MS Subvector User Causes (X 1941) Alert MS Subvector

User Causes (X I011) User Causes Subfield Install Causes (X 195 1) Alert MS Subvector

Install Causes (X 1011) Install Causes Subfield Failure Causes (X 196 1) Alert MS Subvector . . .

Failure Causes (X 1011) Failure Causes Subfield Cause Undetermined (X 197 1) Alert MS Subvector Detailed Data (X 198 I) Alert MS Subvector . . .

Qualified Message Data (X 1011) Detailed Data Subfield Detail Qualifier (EBCDIC) (X I AO I) Alert MS Subvector Detail Qualifier (Hexadecimal) (X I A11) Alert MS Subvector Network Alert (X 10000 I) Common Subfields . . . .

8-2 8-2 8-2 8-2 8-2 8-3 8-4 8-4 8-4 8-4 8-5 8-6 8-6 8-7 8-7 8-8 8-8 8-10 8-11 8-11 8-11 8-12 8-12 8-13 8-13 8-16 8-16 8-16 8-16 8-17 8-17 8-17 8-18 8-18 8-19 8-19 8-24 8-35 8-52 8-53 8-62 8-63 8-70 8-70 8-93 8-94 8-94 8-96 8-96 8-97

Request Change Control (X I8050 1) MS Major Vector ..

Request Change Control MS Subvectors . . . . Install (X 1811) Request Change Control MS Subvector

Removability (X 120 I) Install Subfield Activation Use (X 130 I) Install Subfield Pre-Test (X 140 I) Install Subfield

Automatic Removal (X I50 1) Install Subfield Post-Test (X I60 1) Install Subfield . . . . Automatic Acceptance (X 170 I) Install Subfield . Remove (X 183 1) Request Change Control MS Subvector

Post-Test (X 160 I) Remove Subfield . . . . Accept (X 185 1) Request Change Control MS Subvector .

Corequisite Change (X 187 1) Request Change Control MS Subvector Change Control (X I0050 1) MS Major Vector . . . . Change Control MS Subvectors . . . . Reporting Installation (X 182 I) Change Control MS Subvector Installation Status (X 110 I) Reporting Installation Subfield Removability Status (XI201) Reporting Installation Subfield Activation Use Status (X 130 I) Install Subfield . . . . Pre-Test Status (X 140 I) Reporting Installation Subfield

Automatic Removal Status (X 150 I) Reporting Installation Subfield . . . . . Post-Test Status (X 160 I) Reporting Installation Subfield . . . . . . . . Automatic Acceptance Status (X 170 I) Reporting Installation Subfield . . . . Reporting Removal (X 1841) Change Control MS Subvector

Removal Status (X 110 I) Reporting Removal Subfield . . . . Post-Test Status (X I60 1) Reporting Removal Subfield

Reporting Acceptance (X 186 I) Change Control MS Subvector Accept Status (X 110 I) Reporting Acceptance Subfield· . . . Reported Change Name (X 188 I) Change Control MS Subvector

Reporting Secondary Installation (X 18A I) Change Control MS Subvector Installation Status (X 110 I) Reporting Secondary Installation Subfield Activation Use Status (X 130 I) Reporting Secondary Installation Subfield Secondary Installation Change Name (X 18C I) Change Control MS Subvector Reporting Back-Level Status (X 18E I) Change Control MS Subvector .

Back-Level Status (X 110 I) Reporting Back-Level Status Subfield Back-Level Change Name (X 190 I) Change Control MS Subvector Reporting Deletion (X 192 I) Change Control MS Subvector ..

Deletion (X 110 I) Reporting Deletion Subfield . . . . Deleted Change Name (X 1941) Change Control MS Subvector Detailed Data (X 198 I) Change Control MS Subvector

Execute Command (X I80611) MS Major Vector . . . . Reply to Execute Command (X 100611) MS Major Vector . Analyze Status (X 180621) MS Major Vector . . . Reply to Analyze Status (X 100621) MS Major Vector Query Resource Data (X 18063 I) MS Major Vector . Reply to Query Resource Data (X 10063 I) MS Major Vector Test Resource (X I80641) MS Major Vector . . . . Test Resource Subvectors . . . . Test Setup Data (X I80 1) Test Resource MS Subvector

xiv

SNA Formats

8-115 8-116 8-116 8-117 8-117 8-118 8-118 8-118 8-119 8-119 8-120 8-120 8-120 8-121 8-123 8-123 8-123 8-124 8-124 8-125 8-125 8-126 8-126 8-126 8-127 8-127 8-128 8-128 8-128 8-129 8-129 8-130 8-130 8-130 8-131 8-131 8-131 8-132 8-132 8-132 8-133 8-133 8-134 8-135 8-136 8-137 8-138 8-138 8-138

Test Result Data (X 1811) Reply to Test Resource MS Subvector Test Execution Result (X 101 1) Test Result Data Subfield Test Type (X I021) Test Result Data Subfield . . . . Test Request Count (X I03 1) Test Result Data Subfield Test Executed Count (X I041) Test Result Data Subfield Request Activation (X 18066 I) MS Major Vector

Request Activation MS Subvectors . . . .

Activate (X I 811) Request Activation MS Subvector . . . . Force Indication (X 110 I) Activate Subfield . . . . Change Management Activation Use (X 120 I) Activate Subfield . Reply Activation Acceptance (X 10066 1) MS Major Vector . . . . Activation Acceptance MS Subvectors . . . . Activation Acceptance (X 1821) Activation Acceptance MS Subvector

Attempt Status (X 110 I) Activation Acceptance Subfield Send Message to Operator (X 1006F I) MS Major Vector Request Response Time Monitor (X 18080 I) MS Major Vector Request Response Time Monitor Subvectors

RTM Request (X I921) Request RTM MS Subvector RTM Control (X I 94 1) Request RTM MS Subvector Response Time Monitor (X I0080 1) MS Major Vector Response Time Monitor Subvectors . . . .

RTM Status Reply (X I 91 1) RTM MS Subvector RTM Data (X I 93 I) RTM MS Subvector . . . Request Product Set ID (X 18090 I) MS Major Vector Request Product Set ID Subvectors . . . .

Node Identification (X 1811) Request PSID MS Subvector

Node and Port-Attached Devices Identification (X 183 1) Request PSID MS Subvector Reply Product Set ID (X I0090 1) MS Major Vector . . . . Reply Product Set ID Subvectors . . . . Port-Attached Device Configuration Description (X 1821) Reply PSID MS Subvector

Port Number (X 110 I) Port-Attached Device Config. Des. Subfield . . . . Power-on Status (X 120 I) Port-Attached Device Config. Des. Subfield . . . . Power-on Since Last Solicitation (X 130 I) Port-Attached Device Config. Des. Subfield Text Data (XI1300 1) MS Parameter Major Vector

Structured Data (X 11307 1) MS Parameter Major Vector Structured Data Subvectors . . . .

Resource Data (X 180 I) Structured Data MS Subvector

Resource Item Name (X 1011) Resource Item Name Subfield Resource Item Hex Value (X I 02 I) Resource Data Subfield Resource Item Character Value (X 103 1) Resource Data Subfield Resource Item Integer Value (X 1041) Resource Data Subfield Resource Item Bit String Value (X I05 1) Resource Data Subfield Transparent Coded Datastream(X 11309 I) MS Parameter Major Vector Begin Data Parameters (X 1130A I) MS Parameter Major Vector Begin Data Parameters Subvectors . . . .

Resource State (X 182 I) Begin Data Parameters MS Subvector Probable Causes (X I 93 I) Begin Data Parameters MS Subvector End Parameter Data (X 1130B I) MS Parameter Major Vector MS Common Subvectors . . . .

Text Message (XIOOI) MS Common,Subvector . . . .

8-140 8-141 8-141 8-142 8-142 8-142 8-143 8-143 8-143 8-144 8-144 8-145 8-145 8-145 8-146 8-147 8-148 8-148 8-148 8-150 8-151 8-151 8-153 8-154 8-155 8-155 8-156 8-156 8-157 8-157 8-158 8-158 8-158 8-159 8-160 8-160 8-160 8-161 8-161 8-162 8-162 8-162 8-163 8-163 8-164 8-164 8-164 8-165 8-165 8-165

Hierarchy Name List (X 103 I) MS Common'Subvector . . . . . . . 8-167 SNA Address List (X 1041) MS Common Subvector . . . 8-168 Hierarchy/Resource List (X I05 1) MS Common Subvector . . 8-170 Hierarchy Name List (X 110 I) Hierarchy/Resource List Subfield 8-170 Name List (X I06 1) MS Common Subvector . . . 8-172 Associated Resource Name List (X 1011) Name List Subfield 8-172 Destination Application Name (X I50 1) Name List Subfield . 8-173 Qualified Message (XIOAI) MS Common Subvector . . . . . . . 8-173 Message 10 (X 1011) Qualified Message Subfield . . . 8-174 Replacement Text (X 1021) Qualified Message Subfield . . . 8-175 Product Set 10 (XI101) MS Common Subvector . . . . . . 8-175 Product Identifier (X 1111) MS Common Subvector . . . . . . . 8-175 Hardware Product Identifier (XIOOI) Product 10 Subfield . . . 8-178 Emulated Product Identifier (X 101 1) Product 10 Subfield . . . 8-180 Software Product Serviceable Component Identifier (X 1021) Product 10 Subfield 8-180 Software Product Common Level (X I041) Product 10 Subfield . . . 8-181 Software Product Common Name (X 106 1) Product 10 Subfield . . . 8-181 Software Product Customization Identifier (X I071) Product 10 Subfield 8-181 Software Product Program Number (X I08 1) Product 10 Subfield . . . 8-182 Software Product Customization Date and Time (X I09 1) Product 10 Subfield 8-182 Microcode EC Level (XIOB I) Product 10 Subfield . . . 8-183 Hardware Product Common Name (X 10E I) Product 10 Subfield 8-183 Self-Defining Text Message (X 1311) MS Common Subvector . . . 8-184 Coded Character Set 10 (X 102 I) Self-Defining Text Message Subfield . 8-184 National Language 10 (X 112 I) Self-Defining Text Message Subfield 8-185 Sender 10 (X 1211) Self-Defining Text Message Subfield . . . 8-185 Text Message (X 130 I) Self-Defining Text Message Subfield . . . 8-186 Relative Time (X 142 I) MS Common Subvector . . . . . . 8-186 Data Reset Flag (XI45 1) MS Common Subvector . . . . . . . . . . 8-187 Supporting Data Correlation (X 148 I) MS Common Subvector . . . 8-187 Fully-qualified Session PCID (X 160 I) Supporting Data Correlation Subfield 8-188 Detailed Data (X 182 I) Supporting Data Correlation Subfield . . . 8-188 LAN Link Connection Subsystem Data (XI 51 I) Supporting Data Correlation Subfield 8-189 Ring or Bus Identifier (X 1021) LAN Link Connection Subsystem Data Subfield 8-189 Local Individual MAC Address (X 103 1) LAN Link Connection Subsystem Data Subfield 8-190 Remote Individual MAC Address (X 104 1) LAN Link Connection Subsystem Data

Subfield . . . 8-190 LAN Routing Information (X 105 I) LAN Link Connection Subsystem Data Subfield 8-190 Fault Domain Description (X 106 1) LAN Link Connection Subsystem Data Subfield 8-191 Beaconing Data (X I 07 1) LAN Link Connection Subsystem Data Subfield . . . 8-191 Single MAC Address (X 108 1) LAN Link Connection Subsystem Data Subfield .. 8-191 Fault Domain Error Weight Pair (X 109 1) LAN Link Connection Subsystem Data Subfield 8-192 Bridge Identifier (X lOA I) LAN Link Connection Subsystem Data Subfield . . . 8-192 Local Individual MAC Name (X 123 I) LAN Link Connection Subsystem Data Subfield 8-193 Remote Individual MAC Name (X 1241) LAN Li nk Connection Subsystem Data Subfield 8-193 Fault Domain Names (XI26 1) LAN Link Connection Subsystem Data Subfield 8-193 Single MAC Name (X 128 I) LAN Link Connection Subsystem Data Subfield 8-194 Link Connection Subsystem Configuration Data (X 1521) MS Common Subvector 8-194 Port Address (X I011) Link Connection Subsystem Config. Data Subfield 8-195

xvi

SNA Formats

LCS Link Attributes (X I071) Link Connection Subsystem Config. Data Subfield

LPDA Fault LSL Descriptor (X 108 1) Link Connection Subsystem Config. Data Subfield Sense Data (XI7DI) MS Common Subvector

Chapter 9. Sense Data . . . . Request Reject (Category Code = X 108 1) . . . . Request Error (Category Code = X1101) . . . . . State Error (Category Code

=

^{X 120 I)} . . . . . RH Usage Error (Category Code = X 140 I) . . . . . Path Error (Category Code

=

X 180 I) . . . . Chapter 10. Function Management (FM) Headers

FM Header 1 . . . . . . . . FM Header 2

FM Header 3

FM Header 4 . . . . FM Header 5: Attach (LU 6.2)

Access Security Information Subfields PIP Variable . . . .

PI P Subfield . . . . FM Header 5: Attach (Not LU 6.2) . . . . FM Header 6

FM Header 7: Error Description (LU 6.2) ..

FM Header 7: Error Description (Not LU 6.2) FM Header 8 . . . .

FM Header 10

FM Header 12: Security .

Chapter 11. Presentation Services (PS) Headers Presentation Services (PS) Headers

PS Header 10: Sync Point Control . . . .

Chapter 12. GDS Variables for SNA Service Transaction Programs (STPs) List of SNA Service Transaction Programs . . . .

Descriptions of GDS Variables for SNA STPs . . . . Change Number of Sessions (XI12101) GDS Variable Exchange Log Name (X 112111) GDS Variable

Control Point Management Services Unit (X112121) GDS Variable Compare States (X 11213 1) GDS Variable

8-196 8-197 8-197 . 9-1 . 9-2 9-44 9-59 9-61 9-63 10-1 10-2 10-5 10-6 10-7 10-8 10-10 10-10 10-11 10-11 10-12 10-13 10-14 10-15 10-15 10-15 11-1 11-1 11-1 12-1 12-1 12-1 12-1 12-3 12-4 12-4

Chapter 13. SNA/Distribution Services (OS) 13-1

Introduction . . . 13-1

Structure Classifications . . . . 13-1

Length-bounded Structures 13-1

Atomic Structures . . . 13-1

Parent and Child Structures 13-1

Length-Bounded Parent Structures 13-2

Delimited Parent Structures 13-2

Implied Parent Structures 13-2

Segmented Structures 13-2

Properties of Parent Structures 13-2

Header Description Table , . , " " " " " " " " " " " " " " " " " " ' "

Structure Name " " " " " " " " " " " " ' , . , " " " " " " " , . , ' Structure Reference (Struct Ref) " " " " " " " " " " " " " " " " , . , ' Structure Class (Struct Class) " " " " ' , . , " " " " " " " " " " , . , . , ' IOIT " " " " " " " " ' , . , " " " ' , . , " " " " " " " " " ' , . , ' Length " " " " " , . , " " " " ' , .. , " " , .. , " , . , " " " ' , . , . , ' Occurrences " " " " " " " " " " " " " ' , . , " " " " " " " , . , ' Children " " " " " " " " " " " " " " " " " " " " " " ' , . , . , ' Unrecognized Children Allowed (Unrec) " " ' , . , " " " " " " " " " , . , ' Order " " " " ' , . , " " " " " " " " " " " " " " " " " ' , .. , Number (Num) " ' , . , " " " " " " " " " , . , " " " " " " " , . , ' Subtable " " " " " " " " " " , . , ' , . " .. , " " " " " " " " "

. Structure Description " " " " " " " " " ' , . , ' , . , " " " , . , " " ' , .. , Header Description Tables for FS2 Message Units " " " ' , . , " " " " " " " " "

DISTRIBUTION TRANSPORT MESSAGE UNIT (DTMU) . , " , . , " " " " " " " , . , ' DISTRIBUTION REPORT MESSAGE UNIT (DRMU) " " " " " " " " " " " ' , . , ' DISTRIBUTION CONTINUATION MESSAGE UNIT (DCMU) " " " " " " " " " " ' "

SNA CONDITION REPORT " " " " " " " " " " " " " " " " " " " ' "

SENDER EXCEPTION MESSAGE UNIT (SEMU) " " " " " " " ' , . , " " " " ' "

RECEIVER EXCEPTION MESSAGE UNIT (REMU) " " " " " " " " " " " " , . , COMPLETION QUERY MESSAGE UNIT (CQMU) " " " " " " " " " " " " ' , . , COMPLETION REPORT MESSAGE UNIT (CRMU) " " " ' , . , " " " " " " " , . , PURGE REPORT MESSAGE UNIT (PRMU) " " " " " ' , . , " " " , . , " , . , ' "

RESET REQUEST MESSAGE UNIT (RRMU) " .. , " " " , . , " , . , " " " " " "

RESET ACCEPTED MESSAGE UNIT (RAMU) " " ' , . , " " " " " " " " " " "

FS2 Structure Descriptions " ' , . , " " " " " " " " " " " " " " " " " "

Header Description Tables for FS1 Message Units " " " " " " " " " ' . " " ' "

DISTRIBUTION MESSAGE UNIT (DIST _MU) " " " " " , . , " " " " " " " ' "

DIST REPORT OPERANDS " " " " " " " " " " , . , " " " " " ' , . , ' "

SENDER EXCEPTION MESSAGE UNIT (TYPE FS1) " " " , . , " " " " " ' , . , ' "

RECEIVER EXCEPTION MESSAGE UNIT (TYPE FS1) " " " " " " " " " " " ' "

FS1 Structure Descriptions " " " " " " ' , . , " " " " " " " " " " " , . , ' Transaction Program and Server Names " " " " " " " " " " " " " " " ' "

Code Points Used by SNA/DS FS2 " " " " " " " " ' , . , " " " " " " " ' "

Code Points Used by SNA/DS FS1 " " " " " , . , " " " " " " " " " , . " . , Terminology Mappings " " " " " " " " " " " " , . , " " " " , . , " " "

Chapter 14. GOS Variables for General Use " " " " " ' , . , " " " " " ' , . , " "

Application Data (X '12FF I) GDS Variable " ' , . , " " " " " " " " " " " ' "

Null Data (X '12F11) GDS Variable " " , . , " " " ' , . , " " " " " " " " "

User Control Data (X '12F21) GDS Variable " " " " " " " " " , . , ' , . , " ' "

Map Name (X '12F3 1) GDS Variable , , " " " " " " " " ' , " " ' , . . . . Error Data (X'12F4') GDS Variable .. , " " " ' , . " . , .. " . , " ' , . , . . . . " . Error Log (X '12E11) GDS Variable " , . , " , . " . , ' , . , . . . ,." .. , . " . , . Chapter 15. SNA/File Services (FS) . , ' , . , . , . . , . , . . . " . . , . , " , . . , . . . , " , . Encoding Rules and Representations " . . . , " " " " " , . " .. , .. " . " . . . " .

Structure Classifications " . . . . , , , . , . , . , .. , , , , , . , , . , , , , . . . . Length-bounded Structures .. , .. , .. , .. , ' , . " . , ' , .. , . . . . , ' , . . . ,.

Atomic Structures . . . . , " " ' , . , . , . " . , . , " , . , . , ' , . . . , . , . , ' Parent and Child Structures . . . . , . . . " . , " " " " , . , . , " " " ' , .. , . , .

xviii

SNA Formats

13-3 13-3 13-3 13-3 13-4 13-4 13-4 13-4 13-4 13-4 13-4 13-5 13-5 13-6 13-6 13-8 13-9 13-10 13-11 13-11 13-11 13-12 13-12 13-12 13-12 13-13 13-49 13-49 13-51 13-52 13-52 13-53 13-71 13-72 13-73 13-75 14-1 14-2 14-2 14-2 14-2 14-2 14-3 15-1 15-1 15-1 15-1 15-1 15-1

Segmented Structures . . . . . . . . Properties of Parent Structures . . . . Order . . . . Unrecognized Children . . . .

Number of Children . . . .

Header Description Table . . . . . . . . Structure Name . . . . . . . . Structure Reference (Struct Ref) . . . .

Structure Class (Struct Class) . . . .

ID/T . . . . Length . . .

Occurrences Children ..

Unrecognized Children Allowed (Unrec) . . . . Order . . . . Number (Num) . . . . Subtable . . . .

Structure Description . . . . SNA/FS Usage of SNA/DS Encodings . . . . SNA/FS Requests and Reports . . . . Header Description Tables for SNA/FS Encodings . . . . Unit of Work Correlator . . . . SNA/FS Agent Request . . . . . . . . . SNA/FS Server Request . . . . . . . . . SNA/FS Agent Report . . . . . . . . . SNA/FS Server Report . . . . . . . . . Subtables . . . . . . . .

Global Names . . . . Allocation Information

Tokens . . . . SNA Condition Report . . . . Structure Descriptions . . . .

Server Instructions: . . . . Token Attribute Values . . . . Fetching Flag Values . . . . Deleting Flag Values . . . . SNA/FS Data Object Classification Codes . . . . . . . . Code Points Used by SNA/FS . . . . Transaction Program and Server Names . . . .

Global Name Registration . . . . . . . . Appendix A. SNA Character Sets and Symbol-String Types

Symbol-String Type . . . . . . . .

SNA Character Sets and Encodings . . . .

Appendix B. GDS 10 Description and Assignments . . . . Structured Fields . . . . Length (LL) Description . . . . Identifier (10) Description . . . . . . . . Identifier Registry . . . . Appendix C. List of Abbreviations and Symbols . . . .

15-2 15-2 15-2 15-2 15-3 15-3 15-3 15-3 15-3 15-3 15-4 15-4 15-4 15-4 15-4 15-4 15-4 15-5 15-5 15-5 15-6 15-6 15-6 15-7 15-8 15-8 15-9 15-9 15-9 15-10 15-11 15-12 15-20 15-24 15-25 15-26 15-35 15-35 15-36 15-36 A-1 A-1 A-2 8-1 8-1 8-1 8-2 8-2 C-1

XX SNA Formats

1-1.

1-1.

1-2.

1-3.

1-4.

1-5.

1-6.

1-7.

1-8.

1-9.

1-10.

3-1.

4-1.

4-2.

4-3.

5-1.

6-1.

6-2.

8-1.

9-1.

9-2.

10-1.

10-2.

10-3.

10-4.

12-1.

13-1.

13-2.

13-3.

13-4.

13-5.

13-6.

13-7.

13-8.

13-9.

13-10.

13-11.

13-12.

13-13.

13-14.

13-15.

13-16.

14-1.

15-1.

15-2.

15-3.

15-4.

Organization of this Book . . . . Flag Field of Link Header . . . . Shared Trailing/Leading 0 in SDLC Flags . . . . Address Field of Link Header . . . .

. . . . . vii 1-1 1-2 1-2 Control Field of Link Header . . . 1-3 Control Fields for SDLC Commands and Responses-Modulus 8 1-4 Control Fields for SDLC Commands and Responses-Modulus 128 1-5 Information Field of the FRMR Response Frame 1-6 Frame Check Sequence Field of Link Trailer . . . 1-5 Flag Field of Link Trailer . . . 1-7 LLC Commands and Responses . . . 1-8 Transmission Header for FID Type 2 . . . 3-1 RH Formats . . . 4-2 FMD RequesUResponse Combinations for Sessions between Two LU 6.2s . . . 4-6 Request/Response Combinations For TS Profile 4 Sync Points 4-7 RU Sizes Corresponding to Values XI ab 1 in BIND 5-15 TS Profiles and Their Usage . . . 6-1 FM Profiles and Their Usage . . . 6-3 Setting of Bits 1 and 3 of Byte 2 of the RTM Request (X 1 92¹)

Subvector . . . 8-148 Sense Data Format . . . 9-1 Usage of X'1008' Sense Code Specific Information by LU Type 9-54 FM Header Contained in One RU . . . 10-1 FM Header Contained in Two Contiguous RUs of a Chain 10-1 Usage of FM Headers . . . 10-1 LU Types That Support FM Headers . . . 10-2 SNA-Defined Service Transaction Programs . . . 12-1 Distribution Transport Message Unit . . . 13-6 Distribution Report Message Unit . . . 13-8 Distribution Continuation Message Unit . . . 13-9 SNA Condition Report . . . . . . . . 13-10 Sender Exception Message Unit . . . 13-11 Receiver Exception Message Unit . . . 13-11 Completion Query Message Unit . . . 13-11 Completion Report Message Unit . . . 13-12 Purge Report Message Unit . . . . .. . . . 13-12 Reset Request Message Unit . . . . . . . . . 13-12 Reset Accepted Message Unit . . . 13-12 Distribution Message Unit (DIST _MU) . . . 13-49 Distribution Report Operands . . . 13-51

Sender Exception Message Unit (type FS1) 13-52

Receiver Exception Message Unit (type FS1) 13-52 Terminology Mappings . . . 13-75 LU Type 6.2 GDS Variable Code Points . . . 14-1 The SNA/FS Use of the SNA/DS Agent_ Correl. . . . 15-6 The ~NA/FS Use of the SNA/DS Agent_Object for Agent

Requests. . . . 15-6 The SNA/FS Use of the SNA/DS Server_Object for Server

Requests. . . . 15-7 The SNA/FS Use of the SNA/DS Agent_Object for Agent Reports. 15-8

15-7. Subtable Encoding of the Allocation Information. . . . 15-9 15-8. Subtable Encoding of the Global Name Tokens. . . . 15-10 15-9. SNA Condition Report . . . . 15-11 15-9. The SNA/FS Use of the SNA_Condition_Report . 15-11 A-1. Character Sets A, AE, 930, USS, 1134, and 640 . . . A-3 8-1. GDS Structured Field . . . 8-1 8-2. Identifier Registry . . . 8-2

xxii SNA Formats

Two data link controls are described in this chapter: "Synchronous Data Link Control (SOLC)," beginning on this page, and the "Token-Ring Network OLC" on page 1-7.

Synchronous Data Link Control (SDLC)

All transmissions on an SOLC link are organized in a specific format called a frame:

Frame

=

^BLU

=

LH [,I-field], LT where: BLU

=

Basic Link Unit

LH = Link Header I-field = Information field

L T = Link Trailer

Link headers and link trailers contain data link control information for synchro- nous data link control (SOLC) links. An SOLC frame begins with the link header (LH). which has three fields: the Flag, Address, and Control fields. The link trailer (L T) follows the Information field and is three bytes long. The first two bytes make up the Frame Check Sequence field; the last byte, the closing Flag field. The following pages identify the formats and meanings of the bytes in a link header and a link trailer.

Link Header (Flag)

L--L_H-.L. _ _ _ In_f_onn_at_i o_n_F_i_el_d _ _ •••

E

I l-l

1

^F

1

^{A 1 C I}

I l---1

10111111111111101

LH • Link Header LT • Link Trailer F • Flag A • Address C • Control

Figure 1-1. Flag Field of Link Header. Always X'7E', 8'01111110'.

All frames begin with a Flag field. The configuration of the nag is always 01111110 (X'7E'). Because frames also end with nags (see link trailer), the trailing nag of one frame may serve as the leading nag of the next frame.

When receiving, the last 0 in the trailing nag may also be the first 0 in the next leading nag, as Figure 1-2 on page 1-2 illustrates.

Figure 1-2. Shared Trailing/Leading 0 in SDLe Flags

Note: Zero bit insertion between the beginning and ending flags prevents a flag pattern from occurring anywhere else in the frame.

Link Header (Address)

1-2

SNA Formats

LH

I l-l

I

^F

I

^A

I

^C

I

Information Field

rJ l---1

I a ^I a ^I a ^I a ^I a ^I a ^I a ^I a ^I

LH ^a Link Header LT = Link Trailer F = Fl ag A = Address C = Control

Figure 1-3. Address Field of Link Header. B I aaaaaaaa I

The second byte of the link header is the Address field. This address can be:

• a specific link station address -- to only one link station

• a group address -- to one or more link stations

• a broadcast address (X'FF', 8 1111111111) -- to all link stations

• a "no stations" address (X100I).

The "no stations" address is reserved and should not be used for any link station or group of link stations.

Note: The specific link station address of the secondary is used when the trans- mission is going from primary to secondary or from secondary to primary.

LH Information Field

LH " Link Header LT .. Link Trailer F "Flag A II Address

___ j l_ _ _ _ _ _ _ _ _ _ _________

^{C _}

~ :o:t~o

^I

r (Hodulus 8 and Hodulus 128)

1

(Hodulus 128 only)

1 Iclclclclclclclclclclclclclclclcl

Figure 1-4. Control Field of Link Header. B I cccccccc I for modulus 8; B I cccccccc ecce ecce ^I for modulus 128.

The third byte (or third ?nd fourth bytes) of the link header is the Control field.

The Control field contains either an SOLC command or a response. All frames transmitted by a primary station are commands, while frames transmitted by a secondary station are responses. There are three categories of SOLC com- mands and responses:

• Unnumbered Format

• Supervisory Format

• Information Format

Unnumbered Format: These commands and responses have a poll/final (P/F) bit that is set to 1 to solicit a response (P bit) or when it is the last SOLC frame of a transmission (F bit). This bit is a poll bit for commands and a final bit for responses. Each of the Unnumbered Format commands and responses have two possible hex values: one value for when the poll/final bit is 0 and another value for when the poll/final bit is 1.

Supervisory Format: These commands and responses have a varying number of possible hex values. The number of possible hex values corresponds to the receive sequence numbers assigned to this frame and the setting of the P/F bit.

To increase the sequence number modulus from 8 to 128, a two-byte extended Control field is used.

Information Format: These commands and responses also vary in the number of possible hex values. The number of possible hex values correspond to the send and receive sequence numbers assigned to this frame and the setting of the P/F bit. To increase the sequence number modulus from 8 to 128, a two- byte extended Control field is used.

The Information Format is identified by a 0 in the low-order bit of the first or only byte of the Control field. In an Information Format SOLC command or response, the Information field contains a PIU (Path Information Unit). The

1-4

SNA Formats

Figure 1-5 lists the SOLC commands and responses for modulus 8 (one-byte) Control fields; Figure 1-6 lists them for modulus 128 (two-byte) Control fields.

Figure 1-7 describes toe Information field of the Frame Reject (FRMR) response frame, which is one of the unnumbered formats listed in Figure 1-5.

BINARY HEX EQUIVALENT ACRO-

FORHAT CONFIGURATION P/F off,P/F on COHHAND NAHE NYH Unnumbered 000 P/F 0011 X' 03 " X' 13 ' Unnumbered Information UI

Format

000 F 0111 X' 07', X' 17 ' Request Initialization RIH Hode

000 P 0111 X' 07', X' 17 ' Set Initialization Hode SIH 000 F 1111 X'OF', X'lF' Disconnect Hode DH 001 P 0011 X' 23 " X' 33 ' Unnumbered Po 11 UP 010 F 0011 X' 43 " X' 53 ' Request Disconnect RD 010 P 0011 X' 43 " X' 53 ' Disconnect DISC 011 F 0011 X' 63 " X' 73 ' Unnumbered Acknowledgment UA 100 P 0011 X' 83 " X' 93 ' Set Normal Response Hode SNRH 100 F 0111 X' 87 " X' 97 ' Frame Reject FRHR 101 P/F 1111 X' AF', X' BF' Exchange Identification XID 110 P/F 0111 X'C7', X'07' Configure CFGR 110 P 1111 X'CF', X'OF' Set Normal Response Hode SNRHE

Extended

III P/F 0011 X' E3 " X' F3 ' Test TEST

III F 1111 X'EF', X'FF' Beacon BCN

Supervisory RRR P/F 0001 X'xl', X'xl' Receive Ready RR Format

RRR P/F 0101 X' x5 " X' x5 ' Receive Not Ready RNR

RRR P/F 1001 X'x9', X'x9' Reject REJ

Information RRR P/F SSSO X' xx " X' xx ' Numbered Information

Format Present

Notes: P • Poll bit (sent to secondary station) F • Final bit (sent to primary station) RRR • Nr (receive count)

SSS • Ns (send count)

Figure 1-5. Control Fields for SOLC Commands and Responses-Moduh,ls 8

'-... "

Fonnat

Supervisory 0000 0001 RRRR RRR P/F X'Olxx' Receive Ready RR Fonnat

0000 0101 RRRR RRR P/F X'05xx' Receive Not Ready RNR 0000 1001 RRRR RRR P/F X'09xx' Reject REJ Infonnation SSSS SSSO RRRR RRR P/F X'xxxx' Numbered Infonnation

Fonnat Present

Notes: P ^~ Poll bit (sent to secondary station) F ^~ Final bit (sent to primary station) RRR = Nr (receive count)

SSS ~ Ns (send count)

Figure 1-6. Control Fields for SDLC Commands and Responses-Modulus 128

'-ink Trailer (Frame Check Sequence)

LH Infonnation Field

I

r---

^J

FCS

I

^F

I

I x ^I x ^I x ^I x ^I x ^I x ^I x ^I x ^I x ^I x ^I x ^I x ^I x ^I x ^I x ^I x ^I

Figure 1-8. Frame Check Sequence Field of Link Trailer

The Frame Check Sequence field carries information that the receiver uses to checl< the received frame for errors that may have been introduced by the com- munication channel. This field contains a 16-bit check sequence that is the result of a computation on the contents of both the LH (with the exception of the flag) and the Information field at the transmitter. Cyclic redundancy checking (CRC) is used to perform this calculation. The receiver performs a similar com- putation and checks its results.

1-6

SNA Formats

Modulus 128:

Note: For modulus 128, if control field causing FRMR is an unnumbered format (one-byte), it is placed in byte 0 and byte 1 is set to all O's.

Field Description Explanation/Usage

C Control Field

Nr Receive Count

Ns Send Count

Rejection Indicators:

z Count

y Buffer

x I-field

w Command

Control field of the rejected command, as received

This station's present receiver frame count (the existing count prior to FRMR) This station's present transmitter frame count (the existing count prior to FRMR)

o •

no error

1 • Received Nr disagrees with transmitted Ns

o

^{II no error}

1 • Buffer overrun (I-field is too long)

o

^{II no error}

1 ^II Prohibited I-field received

o ..

^{no error}

1 ^II Invalid or nonimplemented command received

Figure 1-7. Information Field of the FRMR Response Frame. modulus 8 and modulus 128. In each byte, the low order bit is sent first and the high order bit is sent last.

r - J ^I

I

^FCS

I

^F

I

r--- ^J

10111111111111101

Figure 1-9. Flag Field of Link Trailer. Always XI7EI, 8¹01111110¹•

All frames end with a Flag field. The configuration of the ending (trailing) nag is the same as that of the beginning (leading) nag that is present in the link header: 01111110 (X'7E').

Token-Ring Network OLe

The token-ring network OLC consists of two sublayers: the medium access control and the logical link control. The medium access control (MAC) sublayer controls the routing of information between the physical layer and the logical link control sublayer. It provides the following functions: address recognition, frame copying, frame delimiting, and 32-bit frame check sequence generation and verification. The logical link control (LLC) sublayer provides sequential, connection-oriented data transfer.

The following commands and responses, a subset of those shown in Figure 1-6, are used by the LLC sublayer in the token-ring network:

1-8

SNA Formats

DISC Command UA Response SABHE Command FRHR Response

XID Command or Response Test Command or Response Supervisory Format Receive Ready

Receive Not Ready Reject

Information Format Numbered Information Present

Figure 1-10. LLC Commands and Responses

The code points associated with these commands and responses are the same as those shown in Figure 1-6.

The token-ring network OLe, in contrast to SOLe, transmits the high-order bit first and the low-order bit last within each byte. Also, zero bit insertion is required on the token-ring network, since the differential Manchester encoding technique is used.

Additional information about the token-ring network OLe architecture is con- tained in the Token-Ring Network Architecture Reference.

Chapter 2. Exchange Identification (XID) Information Fields

This chapter describes the formats of the information field of the DLC XID command and response.

Throughout this book, reserved is used as follows: reserved bits, or fields, are currently set to O's (unless explicitly stated otherwise); reserved values are those that currently are invalid. Correct usage of reserved fields is enforced by the sender; no receive checks are made on these fields.

DLe XID Information-Field Formats

OLC XIO Information Field Byte

o

1 2-517

Bit 0-3

Content

Format of XID I-field:

X 10 1 fixed format: only bytes 0 - 5 are included

X 111 variable format (for T112.0 to T415 node exchanges): bytes O-p are included

X I 2 I reserved

X 13 1 variable format (for T2.1 to T2.1/BF and T2.0 to T5 node exchanges):

bytes O-p are included

X 18 I - X I F I defined for external standards organizations 4 -7 Type of the XID-sending node:

X^I11 T1 X ' 21 T2 X 13 1 reserved

X '41 subarea node (T4 or T5)

Length, in binary, of variable-format XID I-field (bytes O-p); reserved for fixed- format XID I-field

Node Identification

2 - 5 0 -11 Block number: an IBM product specific number; see the individual product specifications for the specific values used

Note: The values all O's and all 1's indicate that bytes 2 - 5 do not contain a unique node identifier.

12 - 31 10 number: a binary value that, together with the block number, identifies a specific station uniquely within a customer network installation; the 10 number can be assigned in various ways, depending on the product; see the individual product specifications for details

End of Format 0

Note: When the Block Number field does not contain all O's or all 1's, a value of all O's in the 10 number indicates that no 10 number has been assigned.

Note: For XID format 3, the contents of bytes 2 - 5 of the node identification field are used in some instances as a role-negotiation-value to resolve contention in protocol roles of nodes, e.g., primary/secondary DLC roles or the ODAI value to be appended to the (OAF', OAF') values assigned at a node. When a role- negotiation value is needed and the node does not supply a unique node iden- tification value, it supplies a random value in the 10 number field.

Chapter 2. XID Information Fields 2-1

OLC XID Information Field Byte

6-p

6-7

8 8

9

10-11

12

Bit

0-1 2

3

4-7

0-1 2-3

4-5

6

7

o

1-15 0-3

4-7

2-2

SNA Formats

Content

Format 1 Continuation Reserved

Link Station and Connection Protocol Flags Reserved

Link-station role of XID sender:

o

sender is a secondary link station (nonnegotiable) 1 sender is a primary link station (nonnegotiable) Reserved

Link-station transmit-receive capability:

X'O' two-way alternating X'1' two-way simultaneous

Characteristics of the node of the XID sender:

Reserved

Segment assembly capability of the path control element of the node:

00 the Mapping field is ignored and PIUs are forwarded unchanged 01 segments are assembled on a link-station basis

10 segments are assembled on a session basis 11 only whole BIUs are allowed

Reserved

Short-hold status (reserved if byte 9, bit 7 is set to 0):

o

sender not already engaged in a logical connection using short-hold mode on this port

1 sender already engaged in a logical connection using short-hold mode on this port

Short-hold capability of the XID sender:

o

short-hold mode not supported 1 short-hold mode supported

Maximum I-field length that the XID sender can receive:

Format flag:

Obits 1-15 contain the maximum I-field length (only value defined) Maximum I-field length, in binary

Reserved

SDLC command/response profile:

X'O' SNA link profile (only value defined)

Note: These profiles refer to the mandatory command/response support on an SDLC link, as follows:

OLC XIO Information Field

Byte Bit

13 0-1

2

3-7 14-15

16 0

1-7

17

Content

For an SDLC link in normal response mode (NRM/NRME), having a point- to-point or multipoint configuration (determined from system definition), the support required is:

Commands I-frames RR RNR

Responses I-frames RR RNR

Test Test

XID XID

SNRM/SNRME UA Disconnect DM

Reject

RD

Frame Reject Reject

Note 1: The RD response is sent by the secondary station if and only if the PU in its node receives a DISCONTACT request from its CPo

Note 2: Reject is required only if both sender and receiver have two-way simultaneous transmit-receive capability.

• For an SDLe link in normal response mode (NRM), having a loop config- uration (determined from system definition), the support required is:

Commands I-frames RR RNR Test XID SNRM Disconnect UP

Configure

Responses I-frames RR RNR Test XID UA DM

Frame Reject Configure Beacon RD

Note: The RD response is sent by the secondary station if and only if the PU in its node receives a DISCONTACT request from its CPo

Reserved

SDLC initialization mode options:

o

SIM and RIM not supported 1 SIM and RIM supported Reserved

Reserved Reserved

Maximum number of I-frames that can be received by the XID sender before an acknowledgment is sent, with an implied modulus for the send and receive sequence counts-less than 8 implies a modulus of 8; 8 or greater implies a modulus of 128

Reserved

Chapter 2. XID Information Fields

2-3

DLC XID Information Field

Byte Bit Content

For byte 9, bit 7

=

⁰ (short-hold mode not supported) 18-p

18 19-p'

SDLC Address Assignment Field

Length (p minus 18), in binary, of the SDLC address to be assigned Secondary station address to be assigned

For byte 9, bit 7 = 1 (short-hold mode supported) 18-p

18 19-n 19 20-n n+1-p

n+1 n+2-p

End of Format 1

6-p 6-7

8-9

o

1

2

2-4

SNA Formats

Short-Hold Mode Dependent Parameters Reserved

Dial Digits of XID Sender Number, in binary, of dial digits

Dial digits: a string of digits, each having the form X ^I Fn ^I (0~n~9)

Dial digits of an available short-hold mode port

Note: This field is included only in an XID from a T4 or T5 node and only for an incoming call on an already logically busy (byte 9, bit 6 = 1) short-hold mode port. If this field is not included, then p =

n.

Number, in binary, of dial digits of an available short-hold mode port, if one exists

Dial digits of an available short-hold mode port: a string of digits, each having the form X ^I Fn ^I (0~nS9)

Note: Byte n + 1 is set to the value X 100 ^I and the n + 2 - p field is not included if no free alternate port is found. In this case, the station may retry later on the same port used for the current XID.

Format 3 Continuation Reserved

Characteristics of the node of the XID sender:

INIT-SELF support:

a

INIT-SELF may be sent to the XID sender

Note: If the XID sender does not contain an SSCP, it forwards any INIT-SELF received to the proper node for processing, which returns the response to the originator of the request.

1 INIT-SELF (and character-coded logon) cannot be sent to the XID sender Note: For bits 0 -1, the value 11 is reserved.

Stand-alone BIND support:

o

BIND may be sent to the XID sender without a prior INITIATE sequence 1 BIND may not be sent to the XID sender

Note: For bits 0 -1, the value 11 is reserved.

Whole-BIND-PIUs generated indicator:

o

this node can generate BIND PIU segments 1 this node does not generate BIND PIU segments

OLC XID Information Field Byte

10

11-16 17

18-n 18

For SDLC 19

19

Bit 3

4-7 8

9-11 12-13

14-15

o

2-7

o

1

Content

Whole-BIND-PIUs required indicator:

o

this node can receive BIND PIU segments 1 this node cannot receive BIND PIU segments Note: The value 10 for bits 2 - 3 is reserved.

Reserved

ACTPU suppression indicator:

o

ACTPU for an SSCP-PU session requested 1 ACTPU for an SSCP-PU session not requested Reserved

XID exchange state:

00 exchange state indicators not supported (set only by implementations not at the current level of SNA)

01 negotiation-proceeding 10 prenegotiation exchange 11 nonactivation exchange Reserved

BIND pacing support over the link:

Adaptive BIND pacing support as a BIND sender:

o

adaptive BIND pacing as a BIND sender not supported 1 adaptive BIND pacing as a BIND sender supported Adaptive BIND pacing support as a BIND receiver:

o

adaptive BIND pacing as a BIND receiver not supported 1 adaptive BIND pacing as a BIND receiver supported

Note: The combinations of values for bits 0 and 1 have the following meanings:

00 means adaptive BIND pacing is not supported; 01 means one-way adaptive BIND pacing is supported; 10 is not used; and 11 means adaptive BIND pacing is fully supported.

Reserved Reserved DLC type:

X'01' SDLC

X '02' System/370 channel to controller DLC DLC Dependent Section

Length, in binary, of the DLC Dependent Section field (Length field includes itself in the length specified.)

Link Station and Connection Protocol Flags Reserved

ABM support indicator:

o

XID sender cannot be an ABM combined station 1 XID sender can be an ABM combined station

OLC XIO Information Field Byte

20 21-22

23

Bit Content

2 - 3 Link-station role of XID sender:

00 sender is a secondary link station (nonnegotiable) 01 sender is a primary link station (nonnegotiable) 10 reserved

11 negotiable (primary or secondary capability)

Note: For ABM stations, the value of bits 2 - 3 is used only for the purposes of OAF'-DAF' assignment and deciding which node sends the Set Mode command.

4-5 Reserved

6 -7 Link-station transmit-receive capability:

0 1-15 0-3 4-7

00 two-way alternating 01 two-way simultaneous Reserved

Maximum BTU length that the XID sender can receive:

Format flag:

Obits 1 -15 contain the maximum BTU length (only value defined) Maximum BTU length, in binary

Reserved

SDLC command/response profile:

X'O' SNA link profile (on.ly value defined)

Note: These profiles refer to the mandatory command/response support on an SDLC link, as follows:

• For an SDLC link in normal response mode (NRM/NRME), having a point- to-point or multipoint configuration (determined from system definition), the support required is:

Commands I-frames RR RNR

Responses I-frames RR RNR

Test Test

XID XID

SNRM/SNRME UA Disconnect DM

Reject

RD

Frame Reject Reject

Note 1: The RD response is sent by the secondary station if and only if the PU in its node receives a DISCONTACT request from its CPo

Note 2: Reject is required only if both sender and receiver have two-way simultaneous transmit-receive capability.

2-6 SNA Formats