Network Working Group O. Nicklass Request for Comments: 5605 RADVISION Ltd. Category: Standards Track T. Nadeau BT July 2009
Managed Objects for ATM over Packet Switched Networks (PSNs)
Abstract
This memo defines a portion of the Management Information Base (MIB) for use with network management protocols in the Internet community. In particular, it describes managed objects for modeling ATM Pseudowire (PW) carrying ATM cells over Packet Switched Networks (PSNs).
Status of This Memo
This document specifies an Internet standards track protocol for the Internet community, and requests discussion and suggestions for improvements. Please refer to the current edition of the "Internet Official Protocol Standards" (STD 1) for the standardization state and status of this protocol. Distribution of this memo is unlimited.
Copyright Notice
Copyright (c) 2009 IETF Trust and the persons identified as the document authors. All rights reserved.
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This document may contain material from IETF Documents or IETF Contributions published or made publicly available before November 10, 2008. The person(s) controlling the copyright in some of this material may not have granted the IETF Trust the right to allow modifications of such material outside the IETF Standards Process. Without obtaining an adequate license from the person(s) controlling the copyright in such materials, this document may not be modified outside the IETF Standards Process, and derivative works of it may not be created outside the IETF Standards Process, except to format it for publication as an RFC or to translate it into languages other than English.
This document describes a model for managing "emulated" ATM services over a Packet Switched Network (PSN).
The document follows the requirements for Pseudowire Emulation Edge- to-Edge [PWREQ]; it is closely related to [ATMENCAP] and [ATMTRANS], which describe the encapsulation of ATM signals and provide the Emulation Service over a Packet Switched Network.
The ATM management model consists of several MIB modules, following the layering model described in the PWE3 Architecture [PWARCH] document. The ATM MIB module described in this document works closely with the MIB modules described in [AToMTC], [AToM], [IFMIB], [PWMIB], and the textual conventions defined in [PWTC]. The conceptual layering and relationship among all of those is described in Figure 1 and in the "Relation to Other PW-MIB Modules" section listed below. An ATM connection will be a pseudowire (PW) connection. It will not be treated as an interface and will therefore not be represented in the ifTable.
The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT", "SHOULD", "SHOULD NOT", "RECOMMENDED", "MAY", and "OPTIONAL" in this document are to be interpreted as described in RFC 2119 [BCP14].
This document follows the terminology used in PW Architecture [PWARCH].
PSN-bound References the traffic direction where an ATM Cell is received, adapted to the packet, assigned a PW label, and sent into the PSN. Within the MIB objects, it is called outbound.
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CE-bound The direction where packets are received from the PSN, cells are reconstructed from the packet payloads, and are sent into the ATM network as cells. Within the MIB objects, it is called inbound.
Adaptation Refers to the method of adapting a "foreign" communications protocol such that it can be carried by a packet switched net (the PSN). For example, in an ATM service, the foreign protocol is ATM. The PSN may be MPLS.
PSN Packet Switched Network.
PSN Tunnel A general term indicating a virtual connection between the two PW edge devices. In practice, this connection is not limited to path-oriented types of PSNs such as MPLS. An example of a non- path-oriented PSN is an IP PSN.
For a detailed overview of the documents that describe the current Internet-Standard Management Framework, please refer to section 7 of RFC 3410 [RFC3410].
Managed objects are accessed via a virtual information store, termed the Management Information Base or MIB. MIB objects are generally accessed through the Simple Network Management Protocol (SNMP).
Objects in the MIB are defined using the mechanisms defined in the Structure of Management Information (SMI). This memo specifies a MIB module that is compliant to the SMIv2, which is described in STD 58, RFC 2578 [RFC2578], STD 58, RFC 2579 [RFC2579] and STD 58, RFC 2580 [RFC2580].
This MIB module is designed to satisfy the following requirements and constraints:
o Fit within the architecture defined by [PWARCH] and [PWMIB].
o Fit within the model for Virtual Path/Virtual Circuit (VP/VC) definitions and management concept as defined in the [AToM] MIB.
o Support manually configured ATM PWs.
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o Support automatically configured ATM PWs.
o Enable the use of any PSN type.
o Support point-to-point ATM PW connections. Point-to-multipoint and multipoint-to-point connections are for future study.
o Allow configuration of all the parameters needed to establish a PW to carry ATM cells.
o Report ATM performance metrics for the ATM PW. This includes cells transmit, Cells dropped, Cells received, and unknownCells. In addition, it reports performance metrics at packet level.
o Support ATM Operations, Administration, and Management (OAM) cells.
o Do not consider Integrated Local Management Interface (ILMI) support.
The MIB structure for defining a PW service is composed of three layers of MIB modules functioning together. This general model is defined in the PWE3 Architecture [PWARCH]. The layering model is intended to sufficiently isolate PW services from the underlying PSN layer that carries the emulated service. This is done at the same time as providing a standard means for connecting any supported services to any supported PSNs.
The first layer, known as the service layer, contains service- specific modules such as the one defined in this document. These modules define service-specific management objects that interface or collaborate with existing MIB modules for the native version of the service. The service-specific module "glues" the standard module to the PWE MIB framework.
The next layer of the PWE MIB framework is comprised of the PW-MIB module [PWMIB]. This module is used to configure general parameters of PW connections that are common to all types of emulated services and PSNs. This layer is connected to the service-specific layer above, and the PSN layer below.
The PSN layer provides PSN-specific modules for each type of PSN. These modules associate the PW with one or more "tunnels" that carry the service over the PSN. These modules are defined in other documents. This module is used to "glue" the PW service to the
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underlying PSN-specific MIB modules. In the case of MPLS, for example, the PW-MPLS MIB [PWMPLSMIB] is used to connect the PW service to either the MPLS-LDP [LDPMIB] or MPLS-TE [TEMIB] MIBs.
[PWTC] defines some of the object types used in these modules.
This section provides an example of using the MIB objects described in section 9 to set up an ATM PW. While this example is not meant to illustrate every permutation of the MIB, it is intended as an aid in the understanding of some key concepts. It is meant to be read after going through the MIB itself. See [PWMIB] for an example of setting up a PSN Tunnel.
The following example illustrates how a user will set up an ATM Adaptation Layer 5 (AAL5) ATM PW on a switch/router with cells entering the switch/router through ATM Interface with IfIndex 1000 [IFMIB], Virtual Path Identifier (VPI) 1 and Virtual Circuit Identifier (VCI) 100 (from an ATM network to a PSN -- outbound direction) and on the way back, it goes out of the switch/router through ATM Interface 1000 with VPI 1 and VCI 100 (PSN to ATM network -- inbound direction).
First create an entry in the PW MIB with pwType atmAal5SduVcc(2), then create entries in the pwAtmCfg table, inbound and outbound tables.
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In PW ATM MIB In pwAtmCfgTable:
pwAtmCfgMaxCellConcatenation 29 pwAtmCfgTimeoutMode enabled(3) pwAtmClpQosMapping false(0) --CLP will not be mapped to QoS pwAtmOamCellSupported true(1) --OAM cells will be supported
It is important to note that the TrafficParamDescr Table is not defined as part of this MIB, although an object pointing to such a table entry exists in all configuration tables of this MIB module. Users can refer to any ATM TrafficDescr (TD) Table if there is a need to overwrite the TD assigned to the ATM endpoint in the ATM service MIB [AToM].
o PW ATM Cfg Table: A table for generic parameters for ATM PW configuration that is applicable for each ATM PW.
o PW ATM Outbound Table: There are two tables to configure an outbound ATM PW depending on the type of service. One table for 1:1 service, and the other for N:1 service and transparent cell mode [ATMTRANS].
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o PW ATM Inbound Table: There are two tables to configure an inbound ATM PW depending on the type of service. One table for 1:1 service, and the other for N:1 service and transparent cell mode.
o PW ATM Perf Table: There are three tables; each contains the relevant time-dependent statistics for an ATM PW Entry. There is a current table, a 15-minute interval table, and a one-day interval table. The tables are aligned with statistic models of other PW services.
IMPORTS MODULE-IDENTITY, OBJECT-TYPE, Counter32, Unsigned32, mib-2 FROM SNMPv2-SMI
MODULE-COMPLIANCE, OBJECT-GROUP FROM SNMPv2-CONF
TruthValue, RowStatus, RowPointer FROM SNMPv2-TC
PerfCurrentCount, PerfIntervalCount FROM PerfHist-TC-MIB
InterfaceIndex FROM IF-MIB
pwIndex FROM PW-STD-MIB
AtmVpIdentifier, AtmVcIdentifier FROM ATM-TC-MIB;
pwAtmMIB MODULE-IDENTITY LAST-UPDATED "200906160000Z" -- 16 June 2009 ORGANIZATION "Pseudowire Emulation Edge-to-Edge (PWE3) Working Group" CONTACT-INFO "Thomas D. Nadeau Postal: BT BT Centre 81 Newgate Street London EC1A 7AJ United Kingdom
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Email: tom.nadeau@bt.com
Orly Nicklass Postal: RADVISION Ltd. 24 Raul Wallenberg Tel Aviv, Israel Email: orlyn@radvision.com
Discussion and general questions should be posed to the PWE3 Working Group (pwe3@ietf.org)."
DESCRIPTION "This MIB contains managed object definitions for pseudowire emulation of ATM over Packet Switched Networks (PSNs).
This MIB supplements the PW-STD-MIB module. The PW-STD-MIB contains structures and MIB associations generic to pseudowire (PW) emulation. PW-specific MIBs (such as this) contain config and stats for specific PW types.
Copyright (c) 2009 IETF Trust and the persons identified as authors of the code. All rights reserved.
Redistribution and use in source and binary forms, with or without modification, are permitted provided that the following conditions are met:
- Redistributions of source code must retain the above copyright notice, this list of conditions and the following disclaimer.
- Redistributions in binary form must reproduce the above copyright notice, this list of conditions and the following disclaimer in the documentation and/or other materials provided with the distribution.
- Neither the name of Internet Society, IETF or IETF Trust, nor the names of specific contributors, may be used to endorse or promote products derived from this software without specific prior written permission.
THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS 'AS IS' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR
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CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
This version of this MIB module is part of RFC 5605; see the RFC itself for full legal notices. "
-- Revision history.
REVISION "200906160000Z" -- 16 June 2009 DESCRIPTION "Initial version published as RFC 5605."
-- ATM PW PSN Bound(Outbound) Table for 1 to 1 connection
pwAtmOutboundTable OBJECT-TYPE SYNTAX SEQUENCE OF PwAtmOutboundEntry MAX-ACCESS not-accessible STATUS current DESCRIPTION "This table specifies the information for an ATM PW to be carried over the PSN in the outbound direction. An entry is created in this table for every entry in the pwTable with a pwType equal to one of the following: atmAal5SduVcc(2), atmCell1to1Vcc(12), atmCell1to1Vpc(13) or atmAal5PduVcc(14), or atmTransparent(3)." ::= { pwAtmObjects 1 }
pwAtmOutboundEntry OBJECT-TYPE SYNTAX PwAtmOutboundEntry MAX-ACCESS not-accessible STATUS current DESCRIPTION "A row in this table represents an ATM PW that needs to be adapted and carried over the PSN. This table is indexed by
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pwIndex from pwTable. Unless otherwise specified, all writeable objects in this table MUST NOT be changed after row activation in the generic pwTable, and values must persist after reboot." REFERENCE "See [PWMIB]."
pwAtmOutboundAtmIf OBJECT-TYPE SYNTAX InterfaceIndex MAX-ACCESS read-create STATUS current DESCRIPTION "The ATM Interface that receives cells from the ATM network." ::= { pwAtmOutboundEntry 1 }
pwAtmOutboundVpi OBJECT-TYPE SYNTAX AtmVpIdentifier MAX-ACCESS read-create STATUS current DESCRIPTION "VPI value of this ATM PW. The value may indicate the translated value when egress generates new VPI." ::= { pwAtmOutboundEntry 2 }
pwAtmOutboundVci OBJECT-TYPE SYNTAX AtmVcIdentifier MAX-ACCESS read-create STATUS current DESCRIPTION "VCI value of this ATM PW. The value may indicate the translated value when egress generates new VCI." ::= { pwAtmOutboundEntry 3 }
STATUS current DESCRIPTION "This object represents a pointer to an ATM traffic-parameter-specific row in either a private or standard table that will be employed while receiving cells from the ATM network. This row should contain a set of self-consistent ATM traffic parameters including the ATM traffic service category. A value of 0.0 indicates Best Effort." ::= { pwAtmOutboundEntry 4 }
pwAtmOutboundRowStatus OBJECT-TYPE SYNTAX RowStatus MAX-ACCESS read-create STATUS current DESCRIPTION "This object is used to create, modify, or delete a row in this table. Unless otherwise specified, all writeable objects in this table MUST NOT be changed after row activation as explained in the pwAtmOutboundEntry. " ::= { pwAtmOutboundEntry 5 }
-- End of ATM PW Outbound Table
-- ATM PW CE Bound(Inbound) Table for 1 to 1 mode
pwAtmInboundTable OBJECT-TYPE SYNTAX SEQUENCE OF PwAtmInboundEntry MAX-ACCESS not-accessible STATUS current DESCRIPTION "This table specifies the information for an ATM PW in the inbound direction." ::= { pwAtmObjects 3 }
pwAtmInboundEntry OBJECT-TYPE SYNTAX PwAtmInboundEntry MAX-ACCESS not-accessible STATUS current DESCRIPTION "A row in this table represents an ATM PW that needs to be sent into the ATM network after reconstructing cells from packets received from a PSN. This table is indexed by pwIndex from pwTable. An entry is created in this table for every entry in the pwTable with a pwType equal to one of the following: atmAal5SduVcc(2), atmCell1to1Vcc(12), atmCell1to1Vpc(13), atmAal5PduVcc(14), or atmTransparent(3). Unless otherwise
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specified, all writeable objects in this table MUST NOT be changed after row activation in the generic pwTable, and values must persist after reboot." REFERENCE "See [PWMIB]."
pwAtmInboundAtmIf OBJECT-TYPE SYNTAX InterfaceIndex MAX-ACCESS read-create STATUS current DESCRIPTION "The ATM Interface that sends cells into the ATM network after reconstructing cells from packets received from a PSN." ::= { pwAtmInboundEntry 1 }
pwAtmInboundVpi OBJECT-TYPE SYNTAX AtmVpIdentifier MAX-ACCESS read-create STATUS current DESCRIPTION "VPI value of this ATM PW. If the pwType is atmTransparent, then the value will be set to zero." ::= { pwAtmInboundEntry 2 }
pwAtmInboundVci OBJECT-TYPE SYNTAX AtmVcIdentifier MAX-ACCESS read-create STATUS current DESCRIPTION "VCI value of this ATM PW. If the pwType is atmTransparent, atmCell1to1Vpc, or atmCellNto1Vpc, then the value will be set to zero." ::= { pwAtmInboundEntry 3 }
pwAtmInboundTrafficParamDescr OBJECT-TYPE
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SYNTAX RowPointer MAX-ACCESS read-create STATUS current DESCRIPTION "This object represents a pointer to an ATM traffic-parameter- specific row in either a private or standard table that will be employed while transmitting into the ATM network. This table contains a set of self-consistent ATM traffic parameters including the ATM traffic service category. A value of 0.0 indicates Best Effort."
::= { pwAtmInboundEntry 4 }
pwAtmInboundRowStatus OBJECT-TYPE SYNTAX RowStatus MAX-ACCESS read-create STATUS current DESCRIPTION "This object is used to create, modify, or delete a row in this table. Unless otherwise specified, all writeable objects in this table MUST NOT be changed after row activation as explained in the pwAtmInboundEntry. " ::= { pwAtmInboundEntry 5 }
-- End of ATM PW Inbound Table
--Generic ATM PW table for all types of ATM PW connection.
pwAtmCfgTable OBJECT-TYPE SYNTAX SEQUENCE OF PwAtmCfgEntry MAX-ACCESS not-accessible STATUS current DESCRIPTION "This table specifies generic information for an ATM PW to be carried over PSN in any mode." ::= { pwAtmObjects 5 }
pwAtmCfgEntry OBJECT-TYPE SYNTAX PwAtmCfgEntry MAX-ACCESS not-accessible STATUS current DESCRIPTION "This table contains a set of parameters for the ATM PW that needs to be adapted and carried over the PSN. This table is indexed by pwIndex from pwTable. An entry is created for every new ATM type associated pwIndex in the pwTable. Unless otherwise specified, all read-write objects in
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this table MAY be changed when the PW is defined as not active, and all RW objects values must persist after reboot." REFERENCE "See [PWMIB]."
pwAtmCfgMaxCellConcatenation OBJECT-TYPE SYNTAX Unsigned32 (1..29) MAX-ACCESS read-write STATUS current DESCRIPTION "The maximum number of ATM cells that can be concatenated into one PW packet towards the PSN. In a non-LDP or other signaling protocol environment, this object MAY be changed at anytime, but traffic might be interrupted; otherwise, it may be changed when PW is not active." ::= { pwAtmCfgEntry 1 }
pwAtmCfgFarEndMaxCellConcatenation OBJECT-TYPE SYNTAX Unsigned32 (1..29) MAX-ACCESS read-write STATUS current DESCRIPTION "The maximum number of ATM cells that can be concatenated into one PW packet towards PSN as reported by the far end. If there is no LDP in use, the object will either return a value of 0 or allow setting it for calculating protocol overhead." ::= { pwAtmCfgEntry 2 }
MAX-ACCESS read-write STATUS current DESCRIPTION "This object determines whether or not a packet can be transmitted to the PSN based on timeout expiration for collecting cells. The actual handling of the timeout is implementation-specific; as such, this object may be changed at any time under proper consideration of the traffic interruption effect." ::= { pwAtmCfgEntry 3 }
pwAtmClpQosMapping OBJECT-TYPE SYNTAX TruthValue MAX-ACCESS read-write STATUS current DESCRIPTION "This object indicates whether the Cell Loss Priority (CLP) bits should be considered when setting the value in the Quality-of-Service fields of the encapsulating protocol (e.g., EXP fields of the MPLS Label Stack). Selecting True allows the drop precedence to be preserved across the PSN. In transparent cell transport, the value of this object MUST be false(2); in other cases, it can be changed at any time." REFERENCE "See section 12 of [ATMENCAP]." ::= { pwAtmCfgEntry 4 }
-- Device capable of implementing N:1, 1:1, and transparent cell -- mode assumes to support the N:1 table for all -- modes with respective applicable setting. -- In such implementation, user can create an entry for either -- 1:1 or transparent cell transport modes only -- in pwAtmInboundNto1Table. The side effect of such -- will be an automatic create of the respective line in the -- pwAtmOutboundNto1Table.
-- ATM PW Outbound Table for N to 1 connection
pwAtmOutboundNto1Table OBJECT-TYPE SYNTAX SEQUENCE OF PwAtmOutboundNto1Entry MAX-ACCESS not-accessible STATUS current DESCRIPTION "This table specifies the information for an ATM PW to be carried over the PSN in the outbound direction. Up to N entries can be created in this table for every
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entry in the pwTable with a pwType equal to: atmCellNto1Vcc(9) or atmCellNto1Vpc(10). An entry can be created only when the VP/VC are known. A single entry will be created in this table for every entry in the pwTable with a pwType equal to one of the following: atmCell1to1Vcc(12), atmCell1to1Vpc(13), atmAal5PduVcc(14), atmAal5SduVcc(2), or atmTransparent(3). " ::= { pwAtmObjects 6 }
pwAtmOutboundNto1Entry OBJECT-TYPE SYNTAX PwAtmOutboundNto1Entry MAX-ACCESS not-accessible STATUS current DESCRIPTION "A row in this table represents an ATM PW that needs to be adapted and carried over PSN. This table is indexed by pwIndex from pwTable and the ATM interface with VPL/VCLs. In atmTransparent(3), Vpi and VCi will be 0xFFFF during set operation. Unless otherwise specified, all read-create objects in this table MUST NOT be changed after row activation and SHOULD remain unchanged after reboot." INDEX { pwIndex, pwAtmOutboundNto1AtmIf , pwAtmOutboundNto1Vpi, pwAtmOutboundNto1Vci } ::= { pwAtmOutboundNto1Table 1 }
pwAtmOutboundNto1AtmIf OBJECT-TYPE SYNTAX InterfaceIndex MAX-ACCESS not-accessible STATUS current DESCRIPTION "The ATM Interface that receives cells from the ATM network." ::= { pwAtmOutboundNto1Entry 1 }
pwAtmOutboundNto1Vpi OBJECT-TYPE
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SYNTAX AtmVpIdentifier MAX-ACCESS not-accessible STATUS current DESCRIPTION "VPI value of this ATM PW. In atmTransparent(3), Vpi will be the equivalent of 0xFFFF." ::= { pwAtmOutboundNto1Entry 2 }
pwAtmOutboundNto1Vci OBJECT-TYPE SYNTAX AtmVcIdentifier MAX-ACCESS not-accessible STATUS current DESCRIPTION "VCI value of this ATM PW. In atmTransparent(3), or the VP case, the value will be the equivalent of 0xFFFF." ::= { pwAtmOutboundNto1Entry 3 }
pwAtmOutboundNto1RowStatus OBJECT-TYPE SYNTAX RowStatus MAX-ACCESS read-create STATUS current DESCRIPTION "This object is used to create, modify or delete a row in this table." ::= { pwAtmOutboundNto1Entry 4 }
pwAtmOutboundNto1TrafficParamDescr OBJECT-TYPE SYNTAX RowPointer MAX-ACCESS read-create STATUS current DESCRIPTION "This object represents a pointer to an ATM traffic-parameter- specific row in either private or standard table that will be employed while receiving cells from the ATM network. This table should contain a set of self-consistent ATM traffic parameters including the ATM traffic service category. A value of 0.0 indicates Best Effort."
::= { pwAtmOutboundNto1Entry 5 }
pwAtmOutboundNto1MappedVpi OBJECT-TYPE SYNTAX AtmVpIdentifier MAX-ACCESS read-create STATUS current DESCRIPTION "The egress-generated VPI value of this ATM PW. The
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entry is valid for PW type of atmCellNto1Vcc(9), atmCellNto1Vpc(10), atmCell1to1Vcc(12), or atmCell1to1Vpc(13). In other types, the value will be the equivalent of 0xFFFF. Value MAY be changed when the PW is defined as not active. " ::= { pwAtmOutboundNto1Entry 6 }
pwAtmOutboundNto1MappedVci OBJECT-TYPE SYNTAX AtmVcIdentifier MAX-ACCESS read-create STATUS current DESCRIPTION "The egress-generated VCI value of this ATM PW. The entry is valid for PW type of atmCellNto1Vcc(9), atmCellNto1Vpc(10), atmCell1to1Vcc(12), or atmCell1to1Vpc(13. In the VP case or other types, the value will be the equivalent of 0xFFFF. Value MAY be changed when the PW is defined as not active." ::= { pwAtmOutboundNto1Entry 7 }
-- ATM PW Inbound Table for N to 1 connection
pwAtmInboundNto1Table OBJECT-TYPE SYNTAX SEQUENCE OF PwAtmInboundNto1Entry MAX-ACCESS not-accessible STATUS current DESCRIPTION "This table specifies the information for an ATM PW to be carried over PSN in the Inbound direction. Up to N entries can be created in this table for every entry in the pwTable with a pwType equal to: atmCellNto1Vcc(9) or atmCellNto1Vpc(10). An entry can be created only when the VP/VC are known. A single entry will be created in this table for every entry in the pwTable with a pwType equal to one of the following: atmCell1to1Vcc(12), atmCell1to1Vpc(13), atmAal5PduVcc(14), atmAal5SduVcc(2), or atmTransparent(3)." ::= { pwAtmObjects 7 }
pwAtmInboundNto1Entry OBJECT-TYPE SYNTAX PwAtmInboundNto1Entry MAX-ACCESS not-accessible STATUS current DESCRIPTION "A row in this table represents an ATM PW that needs to be adapted and carried over PSN. This table is indexed by
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pwIndex from pwTable and the ATM interface with VPL/VCLs. In atmTransparent(3), Vpi and VCi will be 0xFFFF during set operation. Unless otherwise specified, all Read-Create objects in this table MUST NOT be changed after row activation and SHOULD remain unchanged after reboot." INDEX { pwIndex, pwAtmInboundNto1AtmIf , pwAtmInboundNto1Vpi, pwAtmInboundNto1Vci } ::= { pwAtmInboundNto1Table 1 }
pwAtmInboundNto1AtmIf OBJECT-TYPE SYNTAX InterfaceIndex MAX-ACCESS not-accessible STATUS current DESCRIPTION "The ATM Interface that receives cells from the ATM network." ::= { pwAtmInboundNto1Entry 1 }
pwAtmInboundNto1Vpi OBJECT-TYPE SYNTAX AtmVpIdentifier MAX-ACCESS not-accessible STATUS current DESCRIPTION "VPI value of this ATM PW. In atmTransparent(3), Vpi will be the equivalent of 0xFFFF." ::= { pwAtmInboundNto1Entry 2 }
pwAtmInboundNto1Vci OBJECT-TYPE SYNTAX AtmVcIdentifier MAX-ACCESS not-accessible STATUS current DESCRIPTION "VCI value of this ATM PW. In atmTransparent(3), or the VP case, the value will be the equivalent of 0xFFFF." ::= { pwAtmInboundNto1Entry 3 }
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pwAtmInboundNto1RowStatus OBJECT-TYPE SYNTAX RowStatus MAX-ACCESS read-create STATUS current DESCRIPTION "This object is used to create, modify, or delete a row in this table." ::= { pwAtmInboundNto1Entry 4 }
pwAtmInboundNto1TrafficParamDescr OBJECT-TYPE SYNTAX RowPointer MAX-ACCESS read-create STATUS current DESCRIPTION "This object represents a pointer to an ATM traffic-parameter- specific row in either a private or standard table that will be employed while receiving cells from the ATM network. This table should contain a set of self-consistent ATM traffic parameters including the ATM traffic service category. A value of 0.0 indicates Best Effort."
::= { pwAtmInboundNto1Entry 5 }
pwAtmInboundNto1MappedVpi OBJECT-TYPE SYNTAX AtmVpIdentifier MAX-ACCESS read-create STATUS current DESCRIPTION "The generated VPI value of this ATM PW. The entry is valid for PW type of atmCellNto1Vcc(9), atmCellNto1Vpc(10), atmCell1to1Vcc(12), or atmCell1to1Vpc(13). In other types, the value will be the equivalent of 0xFFFF. Value MAY be changed when the PW is defined as not active." ::= { pwAtmInboundNto1Entry 6 }
pwAtmInboundNto1MappedVci OBJECT-TYPE SYNTAX AtmVcIdentifier MAX-ACCESS read-create STATUS current DESCRIPTION "The generated VCI value of this ATM PW. The entry is valid for PW type of atmCellNto1Vcc(9), atmCellNto1Vpc(10), atmCell1to1Vcc(12), or atmCell1to1Vpc(13. In the VP case or other types, the value will be the equivalent of 0xFFFF. Value MAY be changed when the
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PW is defined as not active." ::= { pwAtmInboundNto1Entry 7 }
-- ATM PW Outbound Perf Table
-- The following supplement the counters presented in the -- PW generic MIB
-- ATM PW Performance Current Table.
pwAtmPerfCurrentTable OBJECT-TYPE SYNTAX SEQUENCE OF PwAtmPerfCurrentEntry MAX-ACCESS not-accessible STATUS current DESCRIPTION "The current 15-minute interval counts are in this table. This table provides performance information per ATM PW." ::= { pwAtmObjects 8 }
pwAtmPerfCurrentEntry OBJECT-TYPE SYNTAX PwAtmPerfCurrentEntry MAX-ACCESS not-accessible STATUS current DESCRIPTION "An entry in this table is created by the agent for every pwAtmCfgTable entry. After 15 minutes, the contents of this table entry are copied to a new entry in the pwAtmPerfInterval table and the counts in this entry are reset to zero." INDEX { pwIndex } ::= { pwAtmPerfCurrentTable 1 }
pwAtmPerfCurrentMissingPkts OBJECT-TYPE SYNTAX PerfCurrentCount MAX-ACCESS read-only STATUS current
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DESCRIPTION "Number of missing packets (as detected via control word sequence number gaps)." ::= { pwAtmPerfCurrentEntry 1 }
pwAtmPerfCurrentPktsReOrder OBJECT-TYPE SYNTAX PerfCurrentCount MAX-ACCESS read-only STATUS current DESCRIPTION "Number of packets detected out of sequence (via control word sequence number), but successfully re-ordered. Note: some implementations may not support this feature." ::= { pwAtmPerfCurrentEntry 2 }
pwAtmPerfCurrentPktsMisOrder OBJECT-TYPE SYNTAX PerfCurrentCount MAX-ACCESS read-only STATUS current DESCRIPTION "Number of packets detected out of order (via control word sequence numbers)." ::= { pwAtmPerfCurrentEntry 3 }
pwAtmPerfCurrentPktsTimeout OBJECT-TYPE SYNTAX PerfCurrentCount MAX-ACCESS read-only STATUS current DESCRIPTION "Number of packets transmitted due to timeout expiration while attempting to collect cells." ::= { pwAtmPerfCurrentEntry 4 }
pwAtmPerfCurrentCellsXmit OBJECT-TYPE SYNTAX PerfCurrentCount MAX-ACCESS read-only STATUS current DESCRIPTION "Number of transmitted cells." ::= { pwAtmPerfCurrentEntry 5 }
pwAtmPerfCurrentCellsDropped OBJECT-TYPE SYNTAX PerfCurrentCount MAX-ACCESS read-only STATUS current DESCRIPTION "Number of dropped cells." ::= { pwAtmPerfCurrentEntry 6 }
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pwAtmPerfCurrentCellsReceived OBJECT-TYPE SYNTAX PerfCurrentCount MAX-ACCESS read-only STATUS current DESCRIPTION "Number of received cells." ::= { pwAtmPerfCurrentEntry 7 }
pwAtmPerfCurrentUnknownCells OBJECT-TYPE SYNTAX PerfCurrentCount MAX-ACCESS read-only STATUS current DESCRIPTION "Number of cells received from the PSN with unknown VPI or VCI values. This object is relevant only in N:1 mode." ::= { pwAtmPerfCurrentEntry 8 }
-- End ATM PW Performance Current Interval Table
-- ATM PW Performance Interval Table.
pwAtmPerfIntervalTable OBJECT-TYPE SYNTAX SEQUENCE OF PwAtmPerfIntervalEntry MAX-ACCESS not-accessible STATUS current DESCRIPTION "This table provides performance information per ATM PW similar to the pwAtmPerfCurrentTable above. However, these counts represent historical 15 minute intervals. Typically, this table will have a maximum of 96 entries for a 24 hour period. " ::= { pwAtmObjects 9 }
pwAtmPerfIntervalEntry OBJECT-TYPE SYNTAX PwAtmPerfIntervalEntry MAX-ACCESS not-accessible STATUS current DESCRIPTION "An entry in this table is created by the agent for every pwAtmPerfCurrentEntry that is 15 minutes old. The contents of the Current entry are copied to the new entry here. The Current entry then resets its counts to zero for the next current 15 minute interval. " INDEX { pwIndex, pwAtmPerfIntervalNumber } ::= { pwAtmPerfIntervalTable 1 }
pwAtmPerfIntervalNumber OBJECT-TYPE SYNTAX Unsigned32 (1..96) MAX-ACCESS not-accessible STATUS current DESCRIPTION "A number (normally between 1 and 96 to cover a 24 hour period) that identifies the interval for which the set of statistics is available. The interval identified by 1 is the most recently completed 15 minute interval, and the interval identified by N is the interval immediately preceding the one identified by N-1. The minimum range of N is 1 through 4. The default range is 1 through 32. The maximum value of N is 96." ::= { pwAtmPerfIntervalEntry 1 }
pwAtmPerfIntervalValidData OBJECT-TYPE SYNTAX TruthValue MAX-ACCESS read-only STATUS current DESCRIPTION "This variable indicates if the data for this interval is valid." ::= { pwAtmPerfIntervalEntry 2 }
pwAtmPerfIntervalDuration OBJECT-TYPE SYNTAX Unsigned32 MAX-ACCESS read-only STATUS current DESCRIPTION "The duration of a particular interval in seconds. Adjustments in the system's time-of-day clock, may cause the interval to be greater or less than the normal value. Therefore, this actual interval value is provided." ::= { pwAtmPerfIntervalEntry 3 }
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pwAtmPerfIntervalMissingPkts OBJECT-TYPE SYNTAX PerfIntervalCount MAX-ACCESS read-only STATUS current DESCRIPTION "Number of missing packets (as detected via control word sequence number gaps)." ::= { pwAtmPerfIntervalEntry 4 }
pwAtmPerfIntervalPktsReOrder OBJECT-TYPE SYNTAX PerfIntervalCount MAX-ACCESS read-only STATUS current DESCRIPTION "Number of packets detected out of sequence (via control word sequence number), but successfully re-ordered. Note: some implementations may not support this feature." ::= { pwAtmPerfIntervalEntry 5 }
pwAtmPerfIntervalPktsMisOrder OBJECT-TYPE SYNTAX PerfIntervalCount MAX-ACCESS read-only STATUS current DESCRIPTION "Number of packets detected out of order (via control word sequence numbers)." ::= { pwAtmPerfIntervalEntry 6 }
pwAtmPerfIntervalPktsTimeout OBJECT-TYPE SYNTAX PerfIntervalCount MAX-ACCESS read-only STATUS current DESCRIPTION "Number of packets transmitted due to timeout expiration." ::= { pwAtmPerfIntervalEntry 7 }
pwAtmPerfIntervalCellsXmit OBJECT-TYPE SYNTAX PerfIntervalCount MAX-ACCESS read-only STATUS current DESCRIPTION "Number of transmitted cells." ::= { pwAtmPerfIntervalEntry 8 }
STATUS current DESCRIPTION "Number of dropped cells." ::= { pwAtmPerfIntervalEntry 9 }
pwAtmPerfIntervalCellsReceived OBJECT-TYPE SYNTAX PerfIntervalCount MAX-ACCESS read-only STATUS current DESCRIPTION "Number of received cells." ::= { pwAtmPerfIntervalEntry 10 }
pwAtmPerfIntervalUnknownCells OBJECT-TYPE SYNTAX PerfIntervalCount MAX-ACCESS read-only STATUS current DESCRIPTION "Number of cells received from the PSN with unknown VPI or VCI values. This object is relevant only in N:1 mode." ::= { pwAtmPerfIntervalEntry 11 }
-- End ATM PW Performance Interval Table
-- ATM PW 1day Performance Table
pwAtmPerf1DayIntervalTable OBJECT-TYPE SYNTAX SEQUENCE OF PwAtmPerf1DayIntervalEntry MAX-ACCESS not-accessible STATUS current DESCRIPTION "This table provides performance information per ATM PW similar to the pwAtmPerfIntervalTable above. However, these counters represent historical one-day intervals up to one full month." ::= { pwAtmObjects 10 }
pwAtmPerf1DayIntervalEntry OBJECT-TYPE SYNTAX PwAtmPerf1DayIntervalEntry MAX-ACCESS not-accessible STATUS current DESCRIPTION "An entry is created in this table by the agent for every entry in the pwAtmCfgTable table." INDEX { pwIndex,pwAtmPerf1DayIntervalNumber } ::= { pwAtmPerf1DayIntervalTable 1 }
pwAtmPerf1DayIntervalNumber OBJECT-TYPE SYNTAX Unsigned32 (1..365) MAX-ACCESS not-accessible STATUS current DESCRIPTION "The number of intervals, where 1 indicates current day measured period and 2 and above indicate previous days, respectively." ::= { pwAtmPerf1DayIntervalEntry 1 }
pwAtmPerf1DayIntervalValidData OBJECT-TYPE SYNTAX TruthValue MAX-ACCESS read-only STATUS current DESCRIPTION "This object indicates if the data for this interval is valid." ::= { pwAtmPerf1DayIntervalEntry 2 }
pwAtmPerf1DayIntervalDuration OBJECT-TYPE SYNTAX Unsigned32 MAX-ACCESS read-only STATUS current DESCRIPTION "The duration of a particular interval in seconds. Adjustments in the system's time-of-day clock may cause the interval to be greater or less than the normal value. Therefore, this actual interval value is provided." ::= { pwAtmPerf1DayIntervalEntry 3 }
pwAtmPerf1DayIntervalMissingPkts OBJECT-TYPE SYNTAX Counter32 MAX-ACCESS read-only STATUS current
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DESCRIPTION "Number of missing packets (as detected via control word sequence number gaps)." ::= { pwAtmPerf1DayIntervalEntry 4 }
pwAtmPerf1DayIntervalPktsReOrder OBJECT-TYPE SYNTAX Counter32 MAX-ACCESS read-only STATUS current DESCRIPTION "Number of packets detected out of sequence (via control word sequence number), but successfully re-ordered. Note: some implementations may not support this feature." ::= { pwAtmPerf1DayIntervalEntry 5 }
pwAtmPerf1DayIntervalPktsMisOrder OBJECT-TYPE SYNTAX Counter32 MAX-ACCESS read-only STATUS current DESCRIPTION "Number of packets detected out of order (via control word sequence numbers) and that could not be re-ordered." ::= { pwAtmPerf1DayIntervalEntry 6 }
pwAtmPerf1DayIntervalPktsTimeout OBJECT-TYPE SYNTAX Counter32 MAX-ACCESS read-only STATUS current DESCRIPTION "Number of packets transmitted due to timeout expiration." ::= { pwAtmPerf1DayIntervalEntry 7 }
pwAtmPerf1DayIntervalCellsXmit OBJECT-TYPE SYNTAX Counter32 MAX-ACCESS read-only STATUS current DESCRIPTION "Number of transmitted cells." ::= { pwAtmPerf1DayIntervalEntry 8 }
pwAtmPerf1DayIntervalCellsDropped OBJECT-TYPE SYNTAX Counter32 MAX-ACCESS read-only STATUS current DESCRIPTION "Number of dropped cells." ::= { pwAtmPerf1DayIntervalEntry 9 }
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pwAtmPerf1DayIntervalCellsReceived OBJECT-TYPE SYNTAX Counter32 MAX-ACCESS read-only STATUS current DESCRIPTION "Number of received cells." ::= { pwAtmPerf1DayIntervalEntry 10 }
pwAtmPerf1DayIntervalUnknownCells OBJECT-TYPE SYNTAX Counter32 MAX-ACCESS read-only STATUS current DESCRIPTION "Number of cells received from the PSN with unknown VPI or VCI values. This object is relevant only in N:1 mode." ::= { pwAtmPerf1DayIntervalEntry 11 }
-- End of ATM PW Performance table
pwAtmCompliances OBJECT IDENTIFIER ::= { pwAtmConformance 1 } pwAtmGroups OBJECT IDENTIFIER ::= { pwAtmConformance 2 } pwAtmCompliance MODULE-COMPLIANCE STATUS current DESCRIPTION "The compliance statement for agents that support ATM PW." MODULE -- this module MANDATORY-GROUPS { pwAtmCfgGroup, pwAtmPerfGroup }
OBJECT pwAtmCfgFarEndMaxCellConcatenation MIN-ACCESS read-only DESCRIPTION "The ability to set this object is not required."
GROUP pwAtmOutbound1to1Group DESCRIPTION "This group is mandatory only for implementations that support the ATM PW 1:1 mode and not using the Nto1 table."
GROUP pwAtmInbound1to1Group DESCRIPTION "This group is mandatory only for implementations that support the ATM PW 1:1 mode and not using the Nto1 table."
GROUP pwAtmOutboundNto1Group
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DESCRIPTION "This group is mandatory only for implementations that support the ATM PW N:1 and transparent mode."
GROUP pwAtmInboundNto1Group DESCRIPTION "This group is mandatory only for implementations that support the ATM PW N:1 and transparent mode."
There are a number of management objects defined in this MIB module with a MAX-ACCESS clause of read-write and/or read-create. Such objects may be considered sensitive or vulnerable in some network environments. The support for SET operations in a non-secure environment without proper protection can have a negative effect on network operations. These are the tables and objects and their sensitivity/vulnerability:
The pwAtmOutboundTable, pwAtmInboundTable, pwAtmCfgTable, pwAtmOutboundNto1Table, and pwAtmInboundNto1Table contain objects of ATM PW parameters on a Provider Edge (PE) device. Unauthorized access to objects in these tables could result in disruption of traffic on the network.
The use of stronger mechanisms such as SNMPv3 security should be considered where possible. Specifically, SNMPv3 VACM and USM MUST be used with any SNMPV3 agent, which implements this MIB module. Administrators should consider whether read access to these objects should be allowed, since read access may be undesirable under certain circumstances.
Some of the readable objects in this MIB module (i.e., objects with a MAX-ACCESS other than not-accessible) may be considered sensitive or vulnerable in some network environments. It is thus important to control even GET and/or NOTIFY access to these objects and possibly to even encrypt the values of these objects when sending them over the network via SNMP. These are the tables and objects and their sensitivity/vulnerability:
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The pwATMCfgTable, pwAtmPerfCurrentTable, pwAtmPerfIntervalTable, and pwAtmPerf1DayIntervalTable collectively show the ATM pseudowire connectivity topology and its performance characteristics.
If an Administrator does not want to reveal this information, then these tables should be considered sensitive/vulnerable.
SNMP versions prior to SNMPv3 did not include adequate security. Even if the network itself is secure (for example by using IPsec), even then, there is no control as to who on the secure network is allowed to access and GET/SET (read/change/create/delete) the objects in this MIB module.
It is RECOMMENDED that implementers consider the security features as provided by the SNMPv3 framework (see [RFC3410], section 8), including full support for the SNMPv3 cryptographic mechanisms (for authentication and privacy).
Further, deployment of SNMP versions prior to SNMPv3 is NOT RECOMMENDED. Instead, it is RECOMMENDED to deploy SNMPv3 and to enable cryptographic security. It is then a customer/operator responsibility to ensure that the SNMP entity giving access to an instance of this MIB module is properly configured to give access to the objects only to those principals (users) that have legitimate rights to indeed GET or SET (change/create/delete) them.
[PWTC] Nadeau, T., Ed., Zelig, D., Ed., and O. Nicklass, Ed., "Definitions of Textual Conventions for Pseudowire (PW) Management", RFC 5542, May 2009.
[PWMIB] Nadeau, T., Ed. and D. Zelig, Ed., "Pseudowire (PW) Management Information Base (MIB)", RFC 5601, July 2009.
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[PWMPLSMIB] Zelig, D., Ed. and T. Nadeau, Ed., "Pseudowire (PW) over MPLS PSN Management Information Base (MIB)", RFC 5602, July 2009.
[ATMENCAP] Martini, L., Jayakumar, J., Bocci, M., El-Aawar, N., Brayley, J., and G. Koleyni, "Encapsulation Methods for Transport of Asynchronous Transfer Mode (ATM) over MPLS Networks", RFC 4717, December 2006.
[ATMTRANS] Malis, A., Martini, L., Brayley, J., and T. Walsh, "Pseudowire Emulation Edge-to-Edge (PWE3) Asynchronous Transfer Mode (ATM) Transparent Cell Transport Service", RFC 4816, February 2007.
[AToM] Tesink, K., "Definitions of Managed Objects for ATM Management", RFC 2515, February 1999.
[AToMTC] Noto, M., Spiegel, E., and K. Tesink, "Definitions of Textual Conventions and OBJECT-IDENTITIES for ATM Management", RFC 2514, February 1999.
[LDPMIB] Cucchiara, J., Sjostrand, H., and J. Luciani, "Definitions of Managed Objects for the Multiprotocol Label Switching (MPLS), Label Distribution Protocol (LDP)", RFC 3815, June 2004.
[TEMIB] Srinivasan, C., Viswanathan, A., and T. Nadeau, "Multiprotocol Label Switching (MPLS) Traffic Engineering (TE) Management Information Base (MIB)", RFC 3812, June 2004.
[IFMIB] McCloghrie, K. and F. Kastenholz, "The Interfaces Group MIB", RFC 2863, June 2000.
[RFC2578] McCloghrie, K., Ed., Perkins, D., Ed., and J. Schoenwaelder, Ed., "Structure of Management Information Version 2 (SMIv2)", STD 58, RFC 2578, April 1999.
[RFC2579] McCloghrie, K., Ed., Perkins, D., Ed., and J. Schoenwaelder, Ed., "Textual Conventions for SMIv2", STD 58, RFC 2579, April 1999.
[RFC2580] McCloghrie, K., Perkins, D., and J. Schoenwaelder, "Conformance Statements for SMIv2", STD 58, RFC 2580, April 1999.
[BCP14] Bradner, S., "Key words for use in RFCs to Indicate Requirement Levels", BCP 14, RFC 2119, March 1997.
[PWREQ] Xiao, X., McPherson, D., and P. Pate, "Requirements for Pseudo-Wire Emulation Edge-to-Edge (PWE3)", RFC 3916, September 2004.
[PWARCH] Bryant, S. and P. Pate, "Pseudo Wire Emulation Edge-to- Edge (PWE3) Architecture", RFC 3985, March 2005.
[RFC3410] Case, J., Mundy, R., Partain, D., and B. Stewart, "Introduction and Applicability Statements for Internet- Standard Management Framework", RFC 3410, December 2002.
This document was produced by the PWE3 Working Group. Special thanks to Senthilkumar Sathappan and Marichetty Venkatesan for their initial contribution and to Bert Wijnen for close review and good suggestions.
Authors' Addresses
Orly Nicklass RADVISION Ltd. 24 Raul Wallenberg St. Tel Aviv ISRAEL
Phone: +972 3 7679444 EMail: orlyn@radvision.com
Thomas D. Nadeau BT BT Centre 81 Newgate Street London EC1A 7AJ United Kingdom