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Run idnits with the --verbose option for more detailed information about the items above. -------------------------------------------------------------------------------- 2 Draft PTOPO Discovery Protocol and MIB March 1998 4 5 Physical Topology Discovery Protocol and MIB 7 2 March 1998 9 Andy Bierman 10 Cisco Systems Inc. 11 abierman@cisco.com 13 Keith McCloghrie 14 Cisco Systems Inc. 15 kzm@cisco.com 17 Status of this Memo 19 This document is an Internet-Draft. Internet-Drafts are working 20 documents of the Internet Engineering Task Force (IETF), its areas, and 21 its working groups. Note that other groups may also distribute working 22 documents as Internet-Drafts. 24 Internet-Drafts are draft documents valid for a maximum of six months 25 and may be updated, replaced, or obsoleted by other documents at any 26 time. It is inappropriate to use Internet- Drafts as reference material 27 or to cite them other than as ``work in progress.'' 29 To learn the current status of any Internet-Draft, please check the 30 ``1id-abstracts.txt'' listing contained in the Internet- Drafts Shadow 31 Directories on ds.internic.net (US East Coast), nic.nordu.net (Europe), 32 ftp.isi.edu (US West Coast), or munnari.oz.au (Pacific Rim). 34 1. Introduction 36 This memo defines an experimental protocol, and an experimental portion 37 of the Management Information Base (MIB) for use with network management 38 protocols in the Internet community. In particular, it describes a 39 physical topology discovery protocol and managed objects used for 40 Draft PTOPO Discovery Protocol and MIB March 1998 42 managing the protocol. 44 2. The SNMP Network Management Framework 46 The SNMP Network Management Framework presently consists of three major 47 components. They are: 49 o the SMI, described in RFC 1902 [RFC1902], - the mechanisms used for 50 describing and naming objects for the purpose of management. 52 o the MIB-II, STD 17, RFC 1213 [RFC1213], - the core set of managed 53 objects for the Internet suite of protocols. 55 o the protocol, RFC 1157 [RFC1157] and/or RFC 1905 [RFC1905], - the 56 protocol for accessing managed information. 58 Textual conventions are defined in RFC 1903 [RFC1903], and conformance 59 statements are defined in RFC 1904 [RFC1904]. 61 The Framework permits new objects to be defined for the purpose of 62 experimentation and evaluation. 64 This memo specifies a MIB module that is compliant to the SNMPv2 SMI. A 65 semantically identical MIB conforming to the SNMPv1 SMI can be produced 66 through the appropriate translation. 68 2.1. Object Definitions 70 Managed objects are accessed via a virtual information store, termed the 71 Management Information Base or MIB. Objects in the MIB are defined 72 using the subset of Abstract Syntax Notation One (ASN.1) defined in the 73 SMI. In particular, each object type is named by an OBJECT IDENTIFIER, 74 an administratively assigned name. The object type together with an 75 object instance serves to uniquely identify a specific instantiation of 76 the object. For human convenience, we often use a textual string, 77 termed the descriptor, to refer to the object type. 79 3. Overview 81 There is a need for a standardized way of representing the physical 82 network connections pertaining to a given management domain. A 83 standardized discovery mechanism is also required to increase the 84 Draft PTOPO Discovery Protocol and MIB March 1998 86 likelihood of multi-vendor interoperability of such physical topology 87 management information. 89 This document specifies a discovery protocol, suitable for use with the 90 Physical Topology MIB [PTOPO]. 92 3.1. Terms 94 Some terms are used throughout this document: 96 SNMP Agent 97 This term refers to an SNMP agent co-located with a particular PDP 98 Agent. Specifically, it refers to the SNMP Agent providing PDP MIB, 99 Entity MIB, Interfaces MIB, and possibly PTOPO MIB support for a 100 particular chassis. 102 PDP Agent 103 This term refers to a software entity which implements the PTOPO 104 Discovery Protocol for a particular chassis. 106 3.2. Persistent Identifiers 108 The PTOPO MIB utilizes non-volatile identifiers to distinguish 109 individual chassis and port components. These identifiers are 110 associated with external objects in order to relate topology information 111 to the existing managed objects. 113 In particular, an object from the Entity MIB or Interfaces MIB can be 114 used as the 'reference-point' for a connection component identifier. 116 3.3. Relationship to the Physical Topology MIB 118 The Physical Topology MIB [PTOPO] allows a PDP Agent to expose learned 119 physical topology information, using a standard MIB. PDP is intended to 120 fully support the PTOPO MIB. 122 3.4. Relationship to Entity MIB 124 The Entity MIB [RFC2037] allows the physical component inventory and 125 hierarchy to be identified. The chassis identifier strings passed in 126 PDP messages identify entPhysicalTable entries, and implementation of 127 Draft PTOPO Discovery Protocol and MIB March 1998 129 the entPhysicalTable and entPhysicalXTable (found in 'Entity MIB 130 Extensions for Persistent Component Identification' [ENTITY-EXT]) are 131 required for SNMP agents which also implement the PDP MIB. 133 3.5. Relationship to Interfaces MIB 135 The Interfaces MIB provides a standard mechanism for managing network 136 interfaces. The port identifier strings passed in PDP messages identify 137 ifTable (or entPhysicalTable) entries, and implementation of the ifTable 138 and ifXTable [RFC2233] are required for SNMP agents which also implement 139 the PDP MIB, for the ports which are represented in the Interfaces MIB. 141 4. PTOPO Discovery Protocol 143 This section defines a discovery protocol, suitable for supporting the 144 data requirements of the PTOPO MIB. 146 The PTOPO Discovery Protocol (PDP) is a media independent protocol 147 intended to be run on routers, bridges, access servers, switches, 148 repeaters, etc., allowing a PDP agent to learn SNMP reachability and 149 connection endpoint information from adjacent devices. 151 PDP runs on various media that support Subnetwork Access Protocol 152 (SNAP), and runs over the data-link layer only, allowing two systems 153 running different network layer protocols can learn about each other. 155 Each device configured with an active PDP Agent sends periodic messages 156 to a multicast MAC address on all physical interfaces enabled for PDP 157 transmission, and listens for PDP messages on the same set on 158 interfaces. Each PDP message contains information identifying the source 159 port as a PTOPO connection endpoint identifier. It also contains at 160 least one network address which can be used by an NMS to reach an SNMP 161 agent on the device (via the indicated source port). Each PDP message 162 contains a configurable time-to-live value, which tells the recipient 163 PDP agent when to discard each element of learned topology information. 165 4.1. Frame Encapsulation 167 The following open issues are under consideration by the working group: 169 An EtherType value must be selected to identify PDP messages 170 transmitted over DIX Ethernet, and IEEE 802.3,802.5 media types 172 Draft PTOPO Discovery Protocol and MIB March 1998 174 (using LLC/SNAP encapsulation). 176 A multicast MAC address must be selected for the destination 177 address (DA) field in PDP messages transmitted over DIX Ethernet, 178 IEEE 802.3, and IEEE 802.5 media types. 180 4.2. PDP Forwarding 182 If at all possible, PDP agents are not supposed to forward PDP messages 183 received on any port. However, some devices, such as repeaters, cannot 184 examine each frame received on an interface or port. Such a device will 185 allow PDP messages to be retransmitted on one or more local ports, and 186 will transmit its own PDP messages on those ports as well. These agents 187 are termed 'forwarding' PDP agents. 189 PDP agents located on devices which examine each frame before 190 retransmitting it (e.g., routers and bridges), are expected to process 191 received PDP messages and not retransmit them on any local port. These 192 agents are termed 'non-forwarding' PDP agents. 194 An NMS may find physical topology information about the same physical 195 port, represented by several PTOPO agents. This may occur for one of 196 several reasons, including a mixture of forwarding and non-forwarding 197 PDP agents within a network. 199 4.3. PDP Message Format 201 The basic PDP packet consists of a header, followed by a variable number 202 of variable bindings in an ASN.1/BER encoded 'VarBindList', as indicated 203 in Figure 1. 205 +------------+--------------------------------------+ 206 | header | (ASN.1/BER) VarBindList | 207 +------------+--------------------------------------+ 209 [ Figure 1 -- Basic PDP Message Format ] 211 4.3.1. PDP Header Format 213 The PDP header is a 4 byte header, in network byte order, 214 containing 3 fields, as shown in figure 2: 216 Draft PTOPO Discovery Protocol and MIB March 1998 218 0 1 2 3 219 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 220 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 221 | Version | Flags | Time To Live | 222 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 224 [ figure 2 -- PDP Message Format ] 226 The PDP header contains the following fields: 228 - Version 229 The PDP protocol version number, set to 0x01 for this version of 230 the protocol. 232 - Flags 233 The PDP flags field provide for future header extensions and keep 234 the header word-aligned for easier processing. No flag definition 235 bits are defined at this time. This field must be set to zero in 236 all version 1 PDP messages. 238 - Time to live 239 The number of seconds the information in this PDP message should be 240 regarded as valid by the recipient. Agents of the PTOPO MIB must 241 not return MIB information based on expired PDP messages. The 242 valid range is 0 to 65535 for this field. 244 4.3.2. PDP PDU Encoding 246 Following the PDP header is an SNMP varbind list encoded in ASN.1/BER 247 [ref. TBD], also referred to as the PDP protocol data unit (PDP-PDU). 248 The individual MIB instances contained in a PDP PDU are referred to as 249 PDP data elements. 251 The standard PDP data elements, defined in the PDP Data MIB, are encoded 252 as a VarBindList in each PDP message. This data enables a PDP agent to 253 implement the PTOPO MIB for connections terminating on the local 254 chassis. 256 This section defines the ASN.1 syntax specific to the PDP message. 257 Refer to the Protocol Operations specification [RFC1905] for a complete 258 definition of the 'VarBindList' construct. 260 Note that PDP places no constraints on which MIB instances may be 261 included in a particular VarBindList. 263 Draft PTOPO Discovery Protocol and MIB March 1998 265 PDP-PDU DEFINITIONS ::= BEGIN 267 IMPORTS 268 MODULE-IDENTITY 269 FROM SNMPv2-SMI 270 VarBindList 271 FROM SNMPv2-PDU; 273 PDPv1-PDU MODULE-IDENTITY 274 LAST-UPDATED "9709150000Z" 275 ORGANIZATION "IETF PTOPOMIB Working Group" 276 CONTACT-INFO 277 "PTOPOMIB WG Discussion: 278 ptopo@3com.com 279 Subscription: 280 majordomo@3com.com 281 msg body: [un]subscribe ptopomib 283 Andy Bierman 284 Cisco Systems Inc. 285 170 West Tasman Drive 286 San Jose, CA 95134 287 408-527-3711 288 abierman@cisco.com 290 Keith McCloghrie 291 Cisco Systems Inc. 292 170 West Tasman Drive 293 San Jose, CA 95134 294 408-526-5260 295 kzm@cisco.com" 296 DESCRIPTION 297 "The definition module for version 1 of the PTOPO Discovery 298 Protocol PDU syntax." 299 ::= { experimental xx } 301 PDP-PDU ::= 302 SEQUENCE { 303 pdp-variable-bindings 304 VarBindList 305 } 307 END 308 Draft PTOPO Discovery Protocol and MIB March 1998 310 4.4. PDP Data MIB 312 This section defines the standard data elements which may be contained 313 in PDP messages. These elements are defined as MIB objects, but are 314 only intended to be encoded into PDP PDUs, and not intended to be 315 instrumented by an SNMP agent. 317 The MIB defines six standard data elements: 319 - Chassis ID 320 - Chassis ID Type 321 - Port ID 322 - Port ID Type 323 - Management Address Type 324 - Management Address 326 4.4.1. Definitions 328 PDP-DATA-MIB DEFINITIONS ::= BEGIN 330 IMPORTS 331 MODULE-IDENTITY, OBJECT-TYPE, Integer32 332 FROM SNMPv2-SMI 333 MODULE-COMPLIANCE, OBJECT-GROUP 334 FROM SNMPv2-CONF 335 IANAAddrFamily, PtopoGenAddr, PtopoChassisIdType, 336 PtopoChassisId, PtopoPortIdType, PtopoPortId 337 FROM PTOPO-MIB; 339 pdpDataMIB MODULE-IDENTITY 340 LAST-UPDATED "9709150000Z" 341 ORGANIZATION "IETF PTOPOMIB Working Group" 342 CONTACT-INFO 343 "PTOPOMIB WG Discussion: 344 ptopo@3com.com 345 Subscription: 346 majordomo@3com.com 347 msg body: [un]subscribe ptopomib 349 Andy Bierman 350 Cisco Systems Inc. 351 170 West Tasman Drive 352 San Jose, CA 95134 354 Draft PTOPO Discovery Protocol and MIB March 1998 356 408-527-3711 357 abierman@cisco.com 359 Keith McCloghrie 360 Cisco Systems Inc. 361 170 West Tasman Drive 362 San Jose, CA 95134 363 408-526-5260 364 kzm@cisco.com" 365 DESCRIPTION 366 "The MIB module for describing PDP data elements." 367 ::= { experimental xx } 369 pdpDataMIBObjects OBJECT IDENTIFIER ::= { pdpDataMIB 1 } 371 -- MIB groups 372 pdpDataElements OBJECT IDENTIFIER ::= { pdpDataMIBObjects 1 } 374 -- 375 -- *********************************************************** 376 -- 377 -- P D P D A T A E L E M E N T S 378 -- 379 -- *********************************************************** 380 -- 382 pdpChassisIdType OBJECT-TYPE 383 SYNTAX PtopoChassisIdType 384 MAX-ACCESS read-only 385 STATUS current 386 DESCRIPTION 387 "This object identifies the type of chassis component 388 identifier contained in the pdpChassisId object, within a 389 given PDP message." 390 ::= { pdpDataElements 1 } 392 pdpChassisId OBJECT-TYPE 393 SYNTAX PtopoChassisId 394 MAX-ACCESS read-only 395 STATUS current 396 DESCRIPTION 397 "This object identifies the chassis component of the 398 particular connection endpoint identifier containing the PDP 399 agent transmitting PDP messages. 401 Draft PTOPO Discovery Protocol and MIB March 1998 403 If the chassis ID is unknown for the entry, then this object 404 will contain an empty string." 405 ::= { pdpDataElements 2 } 407 pdpPortIdType OBJECT-TYPE 408 SYNTAX PtopoPortIdType 409 MAX-ACCESS read-only 410 STATUS current 411 DESCRIPTION 412 "This object identifies the type of port component 413 identifier contained in the pdpPortId object, within a given 414 PDP message." 415 ::= { pdpDataElements 3 } 417 pdpPortId OBJECT-TYPE 418 SYNTAX PtopoPortId 419 MAX-ACCESS read-only 420 STATUS current 421 DESCRIPTION 422 "This object identifies the port component of a particular 423 connection endpoint identifier, associated with the port 424 chosen for transmission of a given PDP message. 426 For PDP agents contained within repeaters or concentrators, 427 this object may identify the backplane component chosen for 428 transmission of a given PDP message, instead of a specific 429 port component (attached to the identified backplane). 431 If the port ID is unknown for the entry, then this object 432 will contain an empty string." 433 ::= { pdpDataElements 4 } 435 pdpMgmtAddrType OBJECT-TYPE 436 SYNTAX IANAAddrFamily 437 MAX-ACCESS read-only 438 STATUS current 439 DESCRIPTION 440 "This object identifies the type of network address 441 contained in the pdpMgmtAddr object, within a given PDP 442 message." 443 ::= { pdpDataElements 5 } 445 pdpMgmtAddr OBJECT-TYPE 446 SYNTAX PtopoGenAddr 447 MAX-ACCESS read-only 449 Draft PTOPO Discovery Protocol and MIB March 1998 451 STATUS current 452 DESCRIPTION 453 "This object identifies a particular network address, 454 associated with an SNMP agent which contains additional 455 information pertaining to the connection endpoint identified 456 in a given PDP message. 458 If a management address is unknown for the endpoint 459 described in a given PDP message, then this object will 460 contain an empty string." 461 ::= { pdpDataElements 6 } 463 -- conformance information 464 pdpDataConformance OBJECT IDENTIFIER ::= { pdpDataMIB 2 } 466 pdpDataCompliances OBJECT IDENTIFIER ::= { pdpDataConformance 1 } 467 pdpDataGroups OBJECT IDENTIFIER ::= { pdpDataConformance 2 } 469 -- compliance statements 471 pdpDataCompliance MODULE-COMPLIANCE 472 STATUS current 473 DESCRIPTION 474 "The compliance statement for entities which implement the 475 PTOPO Discovery Protocol." 476 MODULE -- this module 477 MANDATORY-GROUPS { pdpPtopoDataGroup } 479 ::= { pdpDataCompliances 1 } 481 -- MIB groupings 483 pdpPtopoDataGroup OBJECT-GROUP 484 OBJECTS { 485 pdpChassisIdType, 486 pdpChassisId, 487 pdpPortIdType, 488 pdpPortId, 489 pdpMgmtAddrType, 490 pdpMgmtAddr 491 } 492 STATUS current 493 DESCRIPTION 495 Draft PTOPO Discovery Protocol and MIB March 1998 497 "The collection of objects which identify connection 498 endpoint data elements, as used in the PTOPO Discovery 499 Protocol, and represented in the PTOPO MIB. 501 This group is mandatory for agents which implement the PTOPO 502 Discovery Protocol." 503 ::= { pdpDataGroups 1 } 505 END 507 4.5. Protocol Operation 509 An active PDP Agent must perform the following tasks: 511 - transmit PDP messages 512 - process received PDP messages 513 - maintain an instance of the PDP MIB 514 - maintain an instance of the PTOPO MIB 515 - maintain appropriate ifEntry and/or entPhysicalEntry instances 516 - implement ifAlias and/or entPhysicalAlias MIB objects 518 4.5.1. Protocol Initialization 520 Upon system reinitialization, the following tasks are performed by the 521 PDP agent: 523 Non-volatile configuration for the PDP MIB is retrieved if 524 applicable, otherwise appropriate default values are assigned to 525 all PDP configuration variables. 527 If pdpAdminStatus is equal to 'disabled(2)', then PDP 528 initialization is terminated (until such time that the 529 pdpAdminStatus object is set to 'enabled(1)'), otherwise continue. 531 Internal (implementation-specific) data structures are initialized. 532 such that appropriate local physical topology information and PDP 533 transmission parameters are set. 535 4.5.2. Message Encoding 537 This section does not assume a particular buffering strategy, and such 538 details are omitted. 540 Draft PTOPO Discovery Protocol and MIB March 1998 542 4.5.2.1. Header Fields 544 The version field is set to one (0x01). 546 The flags field is set to zero (0x00). 548 The time-to-live field is set to the value obtained by the following 549 formula: 551 TTL = min(65535, (pdpMessageTxInterval * pdpMessageTxHoldMultiplier)) 553 4.5.2.2. VarBindList 555 Each message must contain one instance of each of the six mandatory 556 PDP-PDU data elements, defined in the PDP Data MIB. Additional data 557 elements may be added as maximum frame size permits. 559 ASN.1/BER encoding is defined in [TBD], and is outside the scope of this 560 document. 562 4.5.3. Message Transmission 564 An active PDP agent must transmit a PDP message out each appropriate 565 port, once each message interval, as determined by the 566 pdpMessageTxInterval MIB object. Messages transmitted on repeater 567 devices may be sent for each repeater backplane, once per message 568 interval. Actual transmission intervals should be jittered to prevent 569 synchronization effects. 571 Note that the agent must suppress the transmission of multiple PDP 572 messages during a single message interval, in the event message 573 transmission cannot be restricted to a single port, but rather a group 574 of ports (e.g., a repeater device). 576 In this case, a single port in the port group should be selected (in an 577 implementation-specific manner) to represent the port group. Note that 578 an agent is encouraged to represent port groups as 'backplanes', in the 579 entPhysicalTable of the Entity MIB, rather than individual ports in 580 either the Entity MIB or Interfaces MIB. 582 Regarding the transmission of a single PDP message, for the indicated 583 physical interface contained in the local system: 585 Draft PTOPO Discovery Protocol and MIB March 1998 587 The PDP agent checks for the existence of a pdpSuppressEntry for 588 the port. If an entry exists then this port is skipped, otherwise 589 continue. 591 The PDP message is encapsulated as appropriate for the port. 593 The MAC header is filled in with appropriate SA and DA and 594 EtherType fields. (Ignoring LLC/SNAP details). 596 The frame is transmitted or passed to a lower layer for 597 transmission. 599 The pdpStatsOutPkts counter is incremented for the indicated local 600 port. 602 4.5.4. Received Message Processing 604 An active PDP agent must process PDP messages received on each 605 appropriate port, as such messages arrive. 607 The following sections refer to the reception of a single PDP message, 608 for the indicated physical interface contained in the local system: 610 4.5.4.1. Header Fields 612 The PDP message and the chassis/port indices associated with the 613 receiving port are retrieved. 615 The PDP version and flags field are checked. The version should equal 616 one (0x01) and the flags should equal zero (0x00). If not, the 617 pdpStatsInErrors counter for the receiving port is incremented and 618 processing is terminated; otherwise continue. 620 4.5.4.2. VarBindList 622 The ASN.1/BER portion of the message is decoded. (Such parsing 623 techniques are beyond the scope of this document.) If this portion of 624 the PDP message is not properly encoded, as defined in the PDP Data MIB, 625 then the pdpStatsInErrors counter for the receiving port is incremented, 626 and processing is terminated; otherwise continue. 628 The list of data elements is examined. The agent must skip and ignore 629 Draft PTOPO Discovery Protocol and MIB March 1998 631 PDU data elements unknown to the agent. If any of the mandatory data 632 elements are missing, then the pdpStatsInErrors counter for the 633 receiving port is incremented, and processing is terminated; otherwise 634 continue. 636 The pdpStatsInGoodPkts counter is incremented for the receiving port. 638 4.5.4.3. PTOPO MIB Update 640 If the time-to-live field in the PDP message header is zero then execute 641 this interface shutdown procedure, described below. Processing of the 642 PDP message is now complete. 644 If the time-to-live field is non-zero, then the appropriate 645 ptopoConnEntry is found or created, based on the data elements included 646 in the PDP message. If the indicated entry is dynamic (i.e., 647 ptopoConnIsStatic is true), then the current sysUpTime value is stored 648 in the ptopoConnLastVerifyTime field for the entry. 650 If a ptopoConnEntry was added then the ptopoConnTabInserts counter is 651 incremented. 653 If a ptopoConnEntry of one type was replaced with an entry of a 654 different type, then the ptopoConnTabReplaces counter is incremented. 656 If any ptopoConnEntry was added or deleted, or if information other than 657 the ptopoConnLastVerifyTime changed for any entry due to the processing 658 of this PDP message, then the ptopoLastChangeTime object is set with the 659 current sysUpTime, and a ptopoConfigChange trap event is generated. (See 660 the PTOPO MIB for information on ptopoConfigChange trap generation.) 662 4.5.5. Interface Shutdown Procedure 664 A special procedure exists for the case in which a PDP agent knows a 665 particular port is about to become non-operational. 667 Note that the pdpSuppressTable has precedence over these procedures, and 668 they are only executed if the indicated interface is not specified in 669 the pdpSuppressTable. 671 If any entries are deleted as a result of these procedures, the 672 ptopoConnTabDeletes counter is incremented for each deleted entry. 674 Draft PTOPO Discovery Protocol and MIB March 1998 676 4.5.5.1. PDP Shutdown Transmission 678 In the event an interface, currently configured with PDP message 679 transmission enabled, either becomes disabled for PDP activity, or the 680 interface is administratively disabled, a final PDP message is 681 transmitted with a time to live value of zero (before the interface is 682 disabled). 684 In the event the pdpOperStatus is transitioning to the disabled state, 685 then this shutdown procedure should be executed for all local 686 interfaces. 688 4.5.5.2. PDP Shutdown Reception 690 After reception of a valid PDP message with a time-to-live value equal 691 to zero, the PDP Agent must remove all information in the PTOPO MIB 692 learned from the particular PDP agent, which is associated with the 693 indicated remote connection endpoint. 695 5. PTOPO Discovery Protocol MIB 697 This section defines the MIB used to configure PDP agent behavior. 699 5.1. Definitions 701 PDP-MIB DEFINITIONS ::= BEGIN 703 IMPORTS 704 MODULE-IDENTITY, OBJECT-TYPE, Integer32, Counter32 705 FROM SNMPv2-SMI 706 RowStatus 707 FROM SNMPv2-TC 708 MODULE-COMPLIANCE, OBJECT-GROUP 709 FROM SNMPv2-CONF 710 PhysicalIndex 711 FROM ENTITY-MIB; 713 pdpMIB MODULE-IDENTITY 714 LAST-UPDATED "9707300000Z" 715 ORGANIZATION "IETF PTOPOMIB Working Group" 716 CONTACT-INFO 717 "PTOPOMIB WG Discussion: 719 Draft PTOPO Discovery Protocol and MIB March 1998 721 ptopo@3com.com 722 Subscription: 723 majordomo@3com.com 724 msg body: [un]subscribe ptopomib 726 Andy Bierman 727 Cisco Systems Inc. 728 170 West Tasman Drive 729 San Jose, CA 95134 730 408-527-3711 731 abierman@cisco.com 733 Keith McCloghrie 734 Cisco Systems Inc. 735 170 West Tasman Drive 736 San Jose, CA 95134 737 408-526-5260 738 kzm@cisco.com" 739 DESCRIPTION 740 "The MIB module for managing the Physical Topology Discovery 741 Protocol." 742 ::= { experimental xx } 744 pdpMIBObjects OBJECT IDENTIFIER ::= { pdpMIB 1 } 746 -- MIB groups 747 pdpConfig OBJECT IDENTIFIER ::= { pdpMIBObjects 1 } 748 pdpStats OBJECT IDENTIFIER ::= { pdpMIBObjects 2 } 750 PdpPortIdType ::= TEXTUAL-CONVENTION 751 STATUS current 752 DESCRIPTION 753 "The type of index value used to represent a port component. 755 If an object of this type has a value of 'ifIndexType(1)', 756 then the associated 'port ID' value represents an ifEntry, 757 with the same ifIndex value. 759 If an object of this type has a value of 760 'entPhysicalIndexType(2)', then the associated 'port ID' 761 value represents an entPhysicalEntry, with the same 762 entPhysicalIndex value." 763 SYNTAX INTEGER { 764 ifIndexType(1), 766 Draft PTOPO Discovery Protocol and MIB March 1998 768 entPhysicalIndexType(2) 769 } 771 -- 772 -- *********************************************************** 773 -- 774 -- P D P C O N F I G 775 -- 776 -- *********************************************************** 777 -- 778 -- The Physical Topology Discovery Protocol Configuration Group 780 pdpAdminStatus OBJECT-TYPE 781 SYNTAX INTEGER { 782 enabled(1), 783 disabled(2) 784 } 785 MAX-ACCESS read-write 786 STATUS current 787 DESCRIPTION 788 "The administratively desired status of the the local PDP 789 agent. 791 If the agent is capable of storing non-volatile 792 configuration, then the value of this object must be 793 restored after a re-initialization of the management 794 system." 795 ::= { pdpConfig 1 } 797 pdpOperStatus OBJECT-TYPE 798 SYNTAX INTEGER { 799 enabled(1), 800 disabled(2) 801 } 802 MAX-ACCESS read-only 803 STATUS current 804 DESCRIPTION 805 "The current operational status of the local PDP agent." 806 ::= { pdpConfig 2 } 808 pdpMessageTxInterval OBJECT-TYPE 809 SYNTAX Integer32 (5..32768) 810 UNITS "seconds" 811 MAX-ACCESS read-write 812 STATUS current 814 Draft PTOPO Discovery Protocol and MIB March 1998 816 DESCRIPTION 817 "The interval at which PDP messages are transmitted on 818 behalf of this PDP agent. 820 If the agent is capable of storing non-volatile 821 configuration, then the value of this object must be 822 restored after a re-initialization of the management 823 system." 824 DEFVAL { 60 } 825 ::= { pdpConfig 3 } 827 pdpMessageTxHoldMultiplier OBJECT-TYPE 828 SYNTAX Integer32 (2..10) 829 MAX-ACCESS read-write 830 STATUS current 831 DESCRIPTION 832 "The time-to-live value expressed as a multiple of the 833 pdpMessageTxInterval object. The actual time-to-live value 834 used in PDP messages, transmitted on behalf of this PDP 835 agent, can be expressed by the following formula: 837 TTL = min(65535, (pdpMessageTxInterval * pdpMessageTxHoldMultiplier)) 839 For example, if the value of pdpMessageTxInterval is '60', 840 and the value of pdpMessageTxHoldMultiplier is '3', then the 841 value '180' is encoded in the TTL field in the PDP header. 843 If the agent is capable of storing non-volatile 844 configuration, then the value of this object must be 845 restored after a re-initialization of the management 846 system." 847 DEFVAL { 3 } 848 ::= { pdpConfig 4 } 850 -- 851 -- PdpSuppressTable: 852 -- Disable PDP activity on individual local ports 854 pdpSuppressTable OBJECT-TYPE 855 SYNTAX SEQUENCE OF PdpSuppressEntry 856 MAX-ACCESS not-accessible 857 STATUS current 858 DESCRIPTION 859 "A table controlling PDP message transmission on individual 860 interfaces, ports, or backplanes." 862 Draft PTOPO Discovery Protocol and MIB March 1998 864 ::= { pdpConfig 6 } 866 pdpSuppressEntry OBJECT-TYPE 867 SYNTAX PdpSuppressEntry 868 MAX-ACCESS not-accessible 869 STATUS current 870 DESCRIPTION 871 "PDP message configuration information for a particular 872 port. The port must be contained in the same chassis as the 873 PDP agent. PDP messages will not be transmitted or received 874 on the indicated port, even if the port is enabled. 876 If the agent is capable of storing non-volatile 877 configuration, then each active pdpSuppressEntry must be 878 re-created after a re-initialization of the management 879 system. An agent should store enough information about the 880 associated entPhysicalEntry (e.g., entPhysicalAlias) or 881 ifEntry (e.g. ifAlias), to properly re-create the entry, 882 even if the pdpSuppressChassisId and/or pdpSuppressPortId 883 values change across a system re-initialization." 884 INDEX { 885 pdpSuppressChassisId, 886 pdpSuppressPortIdType, 887 pdpSuppressPortId 888 } 889 ::= { pdpSuppressTable 1 } 891 PdpSuppressEntry ::= SEQUENCE { 892 pdpSuppressChassisId PhysicalIndex, 893 pdpSuppressPortIdType PdpPortIdType, 894 pdpSuppressPortId Integer32, 895 pdpSuppressRowStatus RowStatus 896 } 898 pdpSuppressChassisId OBJECT-TYPE 899 SYNTAX PhysicalIndex 900 MAX-ACCESS not-accessible 901 STATUS current 902 DESCRIPTION 903 "The entPhysicalIndex value used to identify the chassis 904 component associated with this entry. The associated 905 entPhysicalEntry must be active, and the associated 906 entPhysicalClass object must be equal to 'chassis(3)'." 907 ::= { pdpSuppressEntry 1 } 909 Draft PTOPO Discovery Protocol and MIB March 1998 911 pdpSuppressPortIdType OBJECT-TYPE 912 SYNTAX PdpPortIdType 913 MAX-ACCESS not-accessible 914 STATUS current 915 DESCRIPTION 916 "The type of index value contained in the associated 917 pdpSuppressPortId object." 918 ::= { pdpSuppressEntry 2 } 920 pdpSuppressPortId OBJECT-TYPE 921 SYNTAX Integer32 (1..2147483647) 922 MAX-ACCESS not-accessible 923 STATUS current 924 DESCRIPTION 925 "The index value used to identify the port component of this 926 entry. The type of index value depends on the 927 pdpSuppressPortIdType value for this entry. 929 If the associated pdpSuppressPortIdType is equal to 930 'ifIndexType(1)', then this pdpSuppressPortId represents an 931 ifEntry with the same ifIndex value. The associated ifEntry 932 must be active, and represent a physical interface on the 933 local chassis. 935 If the associated pdpSuppressPortIdType is equal to 936 'entPhysicalIndexType(2)', then this pdpSuppressPortId 937 represents an entPhysicalEntry with the same 938 entPhysicalIndex value. The associated entPhysicalEntry 939 must be active, and the associated entPhysicalClass object 940 must be equal to 'port(10)' or 'backplane(4)'. 942 Note that some devices, such as repeaters, cannot restrict 943 frame transmission to a single port, but rather to a group 944 of ports. In such an event, an agent will disable PDP 945 activity on all ports in the port group, if any of the 946 individual ports in the group are specified in this table." 947 ::= { pdpSuppressEntry 3 } 949 pdpSuppressRowStatus OBJECT-TYPE 950 SYNTAX RowStatus 951 MAX-ACCESS read-create 952 STATUS current 953 DESCRIPTION 954 "The status of this entry." 955 ::= { pdpSuppressEntry 4 } 957 Draft PTOPO Discovery Protocol and MIB March 1998 959 -- 960 -- *********************************************************** 961 -- 962 -- P D P S T A T S 963 -- 964 -- *********************************************************** 965 -- 966 -- PDP Stats Group 968 pdpStatsTable OBJECT-TYPE 969 SYNTAX SEQUENCE OF PdpStatsEntry 970 MAX-ACCESS not-accessible 971 STATUS current 972 DESCRIPTION 973 "A table containing PDP statistics for individual ports. 975 Entries are not required to exist in this table while the 976 pdpAdminStatus or pdpOperStatus objects are equal to 977 'disabled(2)'. 979 Entries are not required to exist in this table if a 980 corresponding entry (with identical index values) exists in 981 the pdpSuppressTable." 982 ::= { pdpStats 1 } 984 pdpStatsEntry OBJECT-TYPE 985 SYNTAX PdpStatsEntry 986 MAX-ACCESS not-accessible 987 STATUS current 988 DESCRIPTION 989 "PDP message statistics for a particular port. The port 990 must be contained in the same chassis as the PDP agent." 991 INDEX { 992 pdpStatsChassisId, 993 pdpStatsPortIdType, 994 pdpStatsPortId 995 } 996 ::= { pdpStatsTable 1 } 998 PdpStatsEntry ::= SEQUENCE { 999 pdpStatsChassisId PhysicalIndex, 1000 pdpStatsPortIdType PdpPortIdType, 1001 pdpStatsPortId Integer32, 1002 pdpStatsInGoodPkts Counter32, 1003 pdpStatsInErrors Counter32, 1005 Draft PTOPO Discovery Protocol and MIB March 1998 1007 pdpStatsOutPkts Counter32 1008 } 1010 pdpStatsChassisId OBJECT-TYPE 1011 SYNTAX PhysicalIndex 1012 MAX-ACCESS not-accessible 1013 STATUS current 1014 DESCRIPTION 1015 "The entPhysicalIndex value used to identify the chassis 1016 component associated with this entry. The associated 1017 entPhysicalEntry must be active, and the associated 1018 entPhysicalClass object must be equal to 'chassis(3)'." 1019 ::= { pdpStatsEntry 1 } 1021 pdpStatsPortIdType OBJECT-TYPE 1022 SYNTAX PdpPortIdType 1023 MAX-ACCESS not-accessible 1024 STATUS current 1025 DESCRIPTION 1026 "The type of index value contained in the associated 1027 pdpStatsPortId object." 1028 ::= { pdpStatsEntry 2 } 1030 pdpStatsPortId OBJECT-TYPE 1031 SYNTAX Integer32 (1..2147483647) 1032 MAX-ACCESS not-accessible 1033 STATUS current 1034 DESCRIPTION 1035 "The index value used to identify the port component of this 1036 entry. The type of index value depends on the 1037 pdpStatsPortType value for this entry. 1039 If the associated pdpStatsPortIdType is equal to 1040 'ifIndexType(1)', then this pdpStatsPortId represents an 1041 ifEntry with the same ifIndex value. The associated ifEntry 1042 must be active, and represent a physical interface on the 1043 local chassis. 1045 If the associated pdpStatsPortIdType is equal to 1046 'entPhysicalIndexType(2)', then this pdpStatsPortId 1047 represents an entPhysicalEntry with the same 1048 entPhysicalIndex value. The associated entPhysicalEntry 1049 must be active, and the associated entPhysicalClass object 1050 must be equal to 'port(10)' or 'backplane(4)'." 1051 ::= { pdpStatsEntry 3 } 1053 Draft PTOPO Discovery Protocol and MIB March 1998 1055 pdpStatsInGoodPkts OBJECT-TYPE 1056 SYNTAX Counter32 1057 MAX-ACCESS read-only 1058 STATUS current 1059 DESCRIPTION 1060 "The number of valid PDP messages received by this PDP agent 1061 on the indicated port, while this PDP agent is enabled." 1062 ::= { pdpStatsEntry 4 } 1064 pdpStatsInErrors OBJECT-TYPE 1065 SYNTAX Counter32 1066 MAX-ACCESS read-only 1067 STATUS current 1068 DESCRIPTION 1069 "The number of invalid PDP messages received by this PDP 1070 agent on the indicated port, while this PDP agent is 1071 enabled. A PDP message may be invalid for several reasons, 1072 including: 1073 - invalid MAC header; length or DA fields 1074 - invalid PDP header; version or flags fields 1075 - invalid PDP VarBindList ASN.1/BER encoding 1076 - invalid or missing PDP VarBindList data elements" 1077 ::= { pdpStatsEntry 5 } 1079 pdpStatsOutPkts OBJECT-TYPE 1080 SYNTAX Counter32 1081 MAX-ACCESS read-only 1082 STATUS current 1083 DESCRIPTION 1084 "The number of PDP messages transmitted by this PDP agent on 1085 the indicated port." 1086 ::= { pdpStatsEntry 6 } 1088 -- conformance information 1089 pdpConformance OBJECT IDENTIFIER ::= { pdpMIB 2 } 1091 pdpCompliances OBJECT IDENTIFIER ::= { pdpConformance 1 } 1092 pdpGroups OBJECT IDENTIFIER ::= { pdpConformance 2 } 1094 -- compliance statements 1096 pdpCompliance MODULE-COMPLIANCE 1097 STATUS current 1098 DESCRIPTION 1100 Draft PTOPO Discovery Protocol and MIB March 1998 1102 "The compliance statement for SNMP entities which implement 1103 the PDP MIB." 1104 MODULE -- this module 1105 MANDATORY-GROUPS { pdpConfigGroup, pdpStatsGroup } 1107 ::= { pdpCompliances 1 } 1109 -- MIB groupings 1111 pdpConfigGroup OBJECT-GROUP 1112 OBJECTS { 1113 pdpAdminStatus, 1114 pdpOperStatus, 1115 pdpMessageTxInterval, 1116 pdpMessageTxHoldMultiplier, 1117 pdpSuppressRowStatus 1118 } 1119 STATUS current 1120 DESCRIPTION 1121 "The collection of objects which are used to configure the 1122 PTOPO Discovery Protocol implementation behavior. 1124 This group is mandatory for agents which implement the PTOPO 1125 Discovery Protocol." 1126 ::= { pdpGroups 1 } 1128 pdpStatsGroup OBJECT-GROUP 1129 OBJECTS { 1130 pdpStatsInGoodPkts, 1131 pdpStatsInErrors, 1132 pdpStatsOutPkts 1133 } 1134 STATUS current 1135 DESCRIPTION 1136 "The collection of objects which are used to represent PTOPO 1137 Discovery Protocol statistics. 1139 This group is mandatory for agents which implement the PTOPO 1140 Discovery Protocol." 1141 ::= { pdpGroups 2 } 1143 END 1144 Draft PTOPO Discovery Protocol and MIB March 1998 1146 6. Acknowledgements 1148 The PTOPO Discovery Protocol is a product of the IETF PTOPOMIB Working 1149 Group. 1151 Draft PTOPO Discovery Protocol and MIB March 1998 1153 7. References 1155 [ENTITY-EXT] 1156 Bierman, A., McCloghrie, K., "Entity MIB Extensions for Persistent 1157 Component Identification", draft-bierman-entmib-compid-00.txt, 1158 Cisco Systems, July 1997. 1160 [PTOPO] 1161 Bierman, A., Jones, K., "Physical Topology MIB", draft-ietf- 1162 ptopomib-mib-00.txt, Cisco Systems, Bay Networks, July 1997. 1164 [RFC1157] 1165 Case, J., M. Fedor, M. Schoffstall, J. Davin, "Simple Network 1166 Management Protocol", RFC 1157, SNMP Research, Performance Systems 1167 International, MIT Laboratory for Computer Science, May 1990. 1169 [RFC1213] 1170 McCloghrie, K., and M. Rose, Editors, "Management Information Base 1171 for Network Management of TCP/IP-based internets: MIB-II", STD 17, 1172 RFC 1213, Hughes LAN Systems, Performance Systems International, 1173 March 1991. 1175 [RFC1902] 1176 SNMPv2 Working Group, Case, J., McCloghrie, K., Rose, M., and 1177 S. Waldbusser, "Structure of Management Information for version 2 1178 of the Simple Network Management Protocol (SNMPv2)", RFC 1902, 1179 January 1996. 1181 [RFC1903] 1182 SNMPv2 Working Group, Case, J., McCloghrie, K., Rose, M., and 1183 S. Waldbusser, "Textual Conventions for version 2 of the Simple 1184 Network Management Protocol (SNMPv2)", RFC 1903, January 1996. 1186 [RFC1904] 1187 SNMPv2 Working Group, Case, J., McCloghrie, K., Rose, M., and 1188 S. Waldbusser, "Conformance Statements for version 2 of the Simple 1189 Network Management Protocol (SNMPv2)", RFC 1904, January 1996. 1191 [RFC1905] 1192 SNMPv2 Working Group, Case, J., McCloghrie, K., Rose, M., and 1193 S. Waldbusser, "Protocol Operations for version 2 of the Simple 1194 Network Management Protocol (SNMPv2)", RFC 1905, January 1996. 1196 [RFC2037] 1197 McCloghrie, K., Bierman, A., "Entity MIB using SMIv2", RFC 2037, 1199 Draft PTOPO Discovery Protocol and MIB March 1998 1201 Cisco Systems, October 1996. 1203 [RFC2233] 1204 McCloghrie, K., and Kastenholtz, F., "The Interfaces Group MIB 1205 using SMIv2", RFC 2233, Cisco Systems, FTP Software, November 1997. 1207 Draft PTOPO Discovery Protocol and MIB March 1998 1209 8. Security Considerations 1211 This protocol and associated MIB can expose the existence of physical 1212 components, MAC layer addresses, and network layer addresses, pertaining 1213 to devices within a given network. A network administrator may wish to 1214 restrict access to this management information, using SNMP access 1215 control mechanisms, and restrict PDP message processing to a particular 1216 set of ports, by configuring entries in the pdpSuppressTable. 1218 9. Authors' Addresses 1220 Andy Bierman 1221 Cisco Systems, Inc. 1222 170 West Tasman Drive 1223 San Jose, CA 95134 1224 Phone: 408-527-3711 1225 Email: abierman@cisco.com 1227 Keith McCloghrie 1228 Cisco Systems, Inc. 1229 170 West Tasman Drive 1230 San Jose, CA 95134 1231 Phone: 408-526-5260 1232 Email: kzm@cisco.com 1234 Draft PTOPO Discovery Protocol and MIB March 1998 1236 Table of Contents 1238 1 Introduction .................................................... 1 1239 2 The SNMP Network Management Framework ........................... 2 1240 2.1 Object Definitions ............................................ 2 1241 3 Overview ........................................................ 2 1242 3.1 Terms ......................................................... 3 1243 3.2 Persistent Identifiers ........................................ 3 1244 3.3 Relationship to the Physical Topology MIB ..................... 3 1245 3.4 Relationship to Entity MIB .................................... 3 1246 3.5 Relationship to Interfaces MIB ................................ 4 1247 4 PTOPO Discovery Protocol ........................................ 4 1248 4.1 Frame Encapsulation ........................................... 4 1249 4.2 PDP Forwarding ................................................ 5 1250 4.3 PDP Message Format ............................................ 5 1251 4.3.1 PDP Header Format ........................................... 5 1252 4.3.2 PDP PDU Encoding ............................................ 6 1253 4.4 PDP Data MIB .................................................. 8 1254 4.4.1 Definitions ................................................. 8 1255 4.5 Protocol Operation ............................................ 12 1256 4.5.1 Protocol Initialization ..................................... 12 1257 4.5.2 Message Encoding ............................................ 12 1258 4.5.2.1 Header Fields ............................................. 13 1259 4.5.2.2 VarBindList ............................................... 13 1260 4.5.3 Message Transmission ........................................ 13 1261 4.5.4 Received Message Processing ................................. 14 1262 4.5.4.1 Header Fields ............................................. 14 1263 4.5.4.2 VarBindList ............................................... 14 1264 4.5.4.3 PTOPO MIB Update .......................................... 15 1265 4.5.5 Interface Shutdown Procedure ................................ 15 1266 4.5.5.1 PDP Shutdown Transmission ................................. 16 1267 4.5.5.2 PDP Shutdown Reception .................................... 16 1268 5 PTOPO Discovery Protocol MIB .................................... 16 1269 5.1 Definitions ................................................... 16 1270 6 Acknowledgements ................................................ 26 1271 7 References ...................................................... 27 1272 8 Security Considerations ......................................... 29 1273 9 Authors' Addresses .............................................. 29