Network Working Group M. Krishnaswamy Request for Comments: 3055 Photuris, Inc. Category: Standards Track D. Romascanu Avaya Communication February 2001
Management Information Base for the PINT Services Architecture
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) The Internet Society (2001). All Rights Reserved.
Abstract
This memo describes a proposed Management Information Base (MIB) for the PSTN/Internet Interworking (PINT) Services Architecture.
PINT services are an emerging set of new Internet based applications where voice (and fax) requests to the PSTN (Public Switched Telephone Network) are carried over the Internet. RFC 2458 [1] gives a good introduction to the (pre-standard) PINT architecture and services. It also has examples of some of the early implementations of pre- PINT.
This document defines a MIB which contains the elements for monitoring the performance of a PINT based service. The MIB consists of details of the four basic PINT services and their performance statistics measured under various criteria.
It is not the purpose of this MIB to enable management of the PINT networking elements. We are concerned only with the PINT specific performance parameters. While it is understood that PINT service performance is closely related to host and network performance, they are not addressed here.
The SNMP Management Framework presently consists of five major components:
o An overall architecture, described in RFC 2571 [2].
o Mechanisms for describing and naming objects and events for the purpose of management. The first version of this Structure of Management Information (SMI) is called SMIv1 and described in STD 16, RFC 1155 [3], STD 16, RFC 1212 [4] and RFC 1215 [5]. The second version, called SMIv2, is described in STD 58, RFC 2578 [6], RFC 2579 [7] and RFC 2580 [8].
o Message protocols for transferring management information. The first version of the SNMP message protocol is called SNMPv1 and described in STD 15, RFC 1157 [9]. A second version of the SNMP message protocol, which is not an Internet standards track protocol, is called SNMPv2c and described in RFC 1901 [10] and RFC 1906 [11]. The third version of the message protocol is called SNMPv3 and described in RFC 1906 [11], RFC 2572 [12] and RFC 2574 [13].
o Protocol operations for accessing management information. The first set of protocol operations and associated PDU formats is described in STD 15, RFC 1157 [9]. A second set of protocol operations and associated PDU formats is described in RFC 1905 [14].
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RFC 3055 PINT MIB February 2001
o A set of fundamental applications described in RFC 2573 [15] and the view-based access control mechanism described in RFC 2575 [16].
A more detailed introduction to the current SNMP Management Framework can be found in RFC 2570 [17].
Managed objects are accessed via a virtual information store, termed the Management Information Base or MIB. Objects in the MIB are defined using the mechanisms defined in the SMI.
This memo specifies a MIB module that is compliant to the SMIv2. A MIB conforming to the SMIv1 can be produced through the appropriate translations. The resulting translated MIB must be semantically equivalent, except where objects or events are omitted because no translation is possible (use of Counter64). Some machine-readable information in SMIv2 will be converted into textual descriptions in SMIv1 during the translation process. However, this loss of machine readable information is not considered to change the semantics of the MIB.
Traditionally voice (and fax) requests originate and terminate inside a PSTN network. This network is well known for robust handling of the requests, in terms of availability and security. However when the requests originate from the Internet there is a concern both on the part of the user as well as the provider about issues like reliable forwarding of the call requests to the PINT gateway under various network conditions, user/host authentication, secure handling of the user information etc. Performance and security management becomes all the more important where PINT services cross multiple administrative domains (or providers).
This MIB is an attempt to list the parameters that need to be monitored on an user, PINT client, PINT server and PINT gateway basis.
(PINT services, their invocation methods/protocols and security issues associated with the PINT architecture are discussed in detail in [18]).
Following is a list of some explanations on the MIB definitions that we have chosen to construct.
o The basic purpose of this MIB is to monitor the access to PINT services both from the performance and security point of view. Information may pertain to a certain user or his/her system (PINT client) or the system providing the PINT services (PINT server) or the PINT gateway that forwards the call to the PSTN network.
o We chose to build the configuration table as an extension of the Application MIB - RFC 2287 [19] using the augments construct. Server location and contact might be retrieved from the standard MIB-II sysLocation and sysContact objects. There is no need to replicate this information in the PINT MIB. However, the PINT administrator may be a different person than the sysadmin with global responsibilities, thus a pintSysContact object is defined.
o We chose to monitor the gateway connections from the PINT server. While the agent runs in the PINT servers, the connections to the gateways might need to be monitored in order to understand what goes on. We placed them in a separate MIB group, and by using MODULE-COMPLIANCE clauses, agents that cannot implement this stuff will not be mandated to do it.
o There is no traps definition in this MIB module. Note that thresholding on counters is always possible by using a standard mechanism defined by the Remote Monitoring MIB, that can be referenced here. Some events that may be defined by using this mechanisms:
* continuous login/authentication failure or refusal from a particular client or user
* nuisance call - repeated calls (within a specified period) to a number originating from the same user
o The client performance and user performance tables may be rather resource demanding for an agent implementation. In some MIBs, like the Remote Monitoring (RMON) MIBs, control mechanisms were built in order to activate those statistics on demand. If needed, a sorting ('topN') mechanism can be designed, so that a sorted view of clients or users is presented for the high level debugging.
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RFC 3055 PINT MIB February 2001
o We built a time-distribution trying to cover both short-lived, as well as longer sessions (1-10 secs, 10 secs - 1 min., 1-15 min., 15 mins-24 hours, longer).
o PintServerClientAddress is defined as a SnmpAdminString. It may include an IpAddress and/or name, but we preferred to minimize the number of indices at this stage, and keep a human-readable format at the same time.
o We define pintServerUserIdName as the UserId. This UserId needs to be unique across multiple PINT servers and gateways (depending on the architecture) and is mapped to the SessionId. One way to achieve this uniqueness is by appending clientId to the UserId string before sending to the PINT server. The SessionId could then be a combination of this new UserId and a timestamp.
IMPORTS OBJECT-TYPE, Counter32, MODULE-IDENTITY, mib-2 FROM SNMPv2-SMI TEXTUAL-CONVENTION FROM SNMPv2-TC MODULE-COMPLIANCE, OBJECT-GROUP FROM SNMPv2-CONF sysApplInstallPkgEntry FROM SYSAPPL-MIB SnmpAdminString FROM SNMP-FRAMEWORK-MIB; -- RFC 2571 [2]
pintMib MODULE-IDENTITY LAST-UPDATED "200102010000Z" -- 1 Feb 2001
ORGANIZATION "IETF PINT Working Group" CONTACT-INFO " Chairs: Steve Bellovin E-mail: smb@research.att.com
Igor Faynberg E-mail: faynberg@lucent.com
Authors: Murali Krishnaswamy Postal: 20 Corporate Place South Piscataway, NJ 08854 Tel: +1 (732)465-1000
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RFC 3055 PINT MIB February 2001
E-mail: murali@photuris.com
Dan Romascanu Postal: Atidim Technology Park, Bldg 3 Tel Aviv, Israel Tel: +972 3 6458414 E-mail: dromasca@avaya.com
General Discussion:pint@lists.bell-labs.com To Subscribe: pint-request@lists.bell-labs.com In Body: subscribe your-email-addres Archive: http://www.bell-labs.com/mailing-lists/pint/ "
DESCRIPTION "This MIB defines the objects necessary to monitor PINT Services"
-- Revision history
REVISION "200102010000Z" -- 1 Feb 2001 DESCRIPTION "Initial version, published as RFC 3055." ::= { mib-2 93 }
PintServiceType ::= TEXTUAL-CONVENTION STATUS current DESCRIPTION "This TC describes the type of a PINT service." SYNTAX INTEGER { r2C(1), -- Request-to-Talk r2F(2), -- Request-to-Fax r2FB(3), -- Request-to-Fax-Back r2HC(4) -- Request-to-Hear-Content }
PintPerfStatPeriod ::= TEXTUAL-CONVENTION STATUS current DESCRIPTION "This TC describes the statistics period of time.
Note that the values of the counters indexed with a value SinceReboot(4) can be potentially affected by a counter rollover. It is the responsibility of the application using this object to take into account that the counter has been zeroed each time it reached a value of (2**32-1)." SYNTAX INTEGER { last30sec(1), -- Performance Statics for the last 30 sec
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RFC 3055 PINT MIB February 2001
last15min(2), -- 15 min last24Hr(3), -- 24 Hour sinceReboot(4) -- Since the time the pint server was -- last rebooted }
pintReleaseNumber OBJECT-TYPE SYNTAX SnmpAdminString MAX-ACCESS read-only STATUS current DESCRIPTION "An indication of version of the PINT protocol supported by this agent." ::= { pintServerConfig 1 }
pintSysContact OBJECT-TYPE SYNTAX SnmpAdminString MAX-ACCESS read-write STATUS current DESCRIPTION "Contact information related to the administration of the PINT services." ::= { pintServerConfig 2 }
pintApplInstallPkgTable OBJECT-TYPE SYNTAX SEQUENCE OF PintApplInstallPkgEntry MAX-ACCESS not-accessible STATUS current DESCRIPTION "Table describing the PINT applications that are installed." ::= { pintServerConfig 3 }
pintApplInstallPkgEntry OBJECT-TYPE SYNTAX PintApplInstallPkgEntry MAX-ACCESS not-accessible STATUS current DESCRIPTION "Entries per PINT Application." AUGMENTS { sysApplInstallPkgEntry } ::= { pintApplInstallPkgTable 1 }
PintApplInstallPkgEntry ::= SEQUENCE {
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RFC 3055 PINT MIB February 2001
pintApplInstallPkgDescription SnmpAdminString }
pintApplInstallPkgDescription OBJECT-TYPE SYNTAX SnmpAdminString MAX-ACCESS read-only STATUS current DESCRIPTION "Textual description of the installed PINT application." ::= { pintApplInstallPkgEntry 1 }
pintRegisteredGatewayTable OBJECT-TYPE SYNTAX SEQUENCE OF PintRegisteredGatewayEntry MAX-ACCESS not-accessible STATUS current DESCRIPTION "Table describing the registered gateway applications." ::= { pintServerConfig 4 }
pintRegisteredGatewayEntry OBJECT-TYPE SYNTAX PintRegisteredGatewayEntry MAX-ACCESS not-accessible STATUS current DESCRIPTION "Entries per Registered Gateway Application." AUGMENTS { sysApplInstallPkgEntry } ::= { pintRegisteredGatewayTable 1 }
pintRegisteredGatewayName OBJECT-TYPE SYNTAX SnmpAdminString MAX-ACCESS read-only STATUS current DESCRIPTION "Name of the registered gateway." ::= { pintRegisteredGatewayEntry 1 }
pintRegisteredGatewayDescription OBJECT-TYPE SYNTAX SnmpAdminString MAX-ACCESS read-only STATUS current DESCRIPTION "Textual description of the registered gateway." ::= { pintRegisteredGatewayEntry 2 }
pintServerGlobalStatsTable OBJECT-TYPE SYNTAX SEQUENCE OF PintServerGlobalStatsEntry MAX-ACCESS not-accessible STATUS current DESCRIPTION "Table displaying the monitored global server statistics." ::= { pintServerGlobalPerf 1 }
pintServerGlobalStatsEntry OBJECT-TYPE SYNTAX PintServerGlobalStatsEntry MAX-ACCESS not-accessible STATUS current DESCRIPTION "Entries in the global statistics table. One entry is defined for each monitored service type and performance statistics collection period." INDEX {pintServerServiceTypeIndex, pintServerPerfStatPeriodIndex} ::= { pintServerGlobalStatsTable 1 }
pintServerServiceTypeIndex OBJECT-TYPE SYNTAX PintServiceType MAX-ACCESS not-accessible STATUS current DESCRIPTION "The unique identifier of the monitored service." ::= { pintServerGlobalStatsEntry 1 }
STATUS current DESCRIPTION "Time period for which the performance statistics are requested from the pint server." ::= { pintServerGlobalStatsEntry 2 }
pintServerGlobalCallsReceived OBJECT-TYPE SYNTAX Counter32 MAX-ACCESS read-only STATUS current DESCRIPTION "Number of received global calls." ::= { pintServerGlobalStatsEntry 3 }
pintServerGlobalSuccessfulCalls OBJECT-TYPE SYNTAX Counter32 MAX-ACCESS read-only STATUS current DESCRIPTION "Number of global successful calls." ::= { pintServerGlobalStatsEntry 4 }
pintServerGlobalDisconnectedCalls OBJECT-TYPE SYNTAX Counter32 MAX-ACCESS read-only STATUS current DESCRIPTION "Number of global disconnected (failed) calls." ::= { pintServerGlobalStatsEntry 5 }
pintServerGlobalDisCUAutFCalls OBJECT-TYPE SYNTAX Counter32 MAX-ACCESS read-only STATUS current DESCRIPTION "Number of global calls that were disconnected because of client or user authorization failure." ::= { pintServerGlobalStatsEntry 6 }
pintServerGlobalDisServProbCalls OBJECT-TYPE SYNTAX Counter32 MAX-ACCESS read-only STATUS current DESCRIPTION "Number of global calls that were disconnected because of server problems." ::= { pintServerGlobalStatsEntry 7 }
pintServerGlobalDisGatProbCalls OBJECT-TYPE SYNTAX Counter32 MAX-ACCESS read-only STATUS current DESCRIPTION "Number of global calls that were disconnected because of gateway problems." ::= { pintServerGlobalStatsEntry 8 }
pintServerClientStatsTable OBJECT-TYPE SYNTAX SEQUENCE OF PintServerClientStatsEntry MAX-ACCESS not-accessible STATUS current DESCRIPTION "Table displaying the monitored server client statistics." ::= { pintServerClientPerf 1 }
pintServerClientStatsEntry OBJECT-TYPE SYNTAX PintServerClientStatsEntry MAX-ACCESS not-accessible STATUS current DESCRIPTION "Entries in the client server statistics table. One entry is defined for each client identified by name, monitored service type and performance statistics collection period." INDEX {pintServerClientAddress, pintServerServiceTypeIndex, pintServerPerfStatPeriodIndex} ::= { pintServerClientStatsTable 1 }
pintServerClientAddress OBJECT-TYPE SYNTAX SnmpAdminString MAX-ACCESS not-accessible STATUS current DESCRIPTION "The unique identifier of the monitored client identified by its address represented as as a string." ::= { pintServerClientStatsEntry 1 }
pintServerClientCallsReceived OBJECT-TYPE SYNTAX Counter32 MAX-ACCESS read-only STATUS current DESCRIPTION "Number of calls received from the specific client." ::= { pintServerClientStatsEntry 2 }
pintServerClientSuccessfulCalls OBJECT-TYPE SYNTAX Counter32 MAX-ACCESS read-only STATUS current DESCRIPTION "Number of calls from the client successfully completed." ::= { pintServerClientStatsEntry 3 }
pintServerClientDisconnectedCalls OBJECT-TYPE SYNTAX Counter32 MAX-ACCESS read-only STATUS current DESCRIPTION "Number of calls received from the client, and that were disconnected (failed)." ::= { pintServerClientStatsEntry 4 }
pintServerClientDisCAutFCalls OBJECT-TYPE SYNTAX Counter32 MAX-ACCESS read-only STATUS current DESCRIPTION "Number of calls from the client that were disconnected because of client authorization failure." ::= { pintServerClientStatsEntry 5 }
pintServerClientDisEFProbCalls OBJECT-TYPE SYNTAX Counter32 MAX-ACCESS read-only STATUS current DESCRIPTION "Number of calls from the client that were disconnected because of egress facility problems." ::= { pintServerClientStatsEntry 6 }
pintServerUserIdStatsTable OBJECT-TYPE SYNTAX SEQUENCE OF PintServerUserIdStatsEntry MAX-ACCESS not-accessible STATUS current
DESCRIPTION "Table displaying the monitored Pint service user statistics." ::= { pintServerUserIdPerf 1 }
pintServerUserIdStatsEntry OBJECT-TYPE SYNTAX PintServerUserIdStatsEntry MAX-ACCESS not-accessible STATUS current DESCRIPTION "Entries in the user statistics table. One entry is defined for each user identified by name, each monitored service type and performance statistics collection period.
It is assumed that the capabilities of the pint server are enough to accommodate the number of entries in this table. It is a local server implementation issue if an aging mechanism Is implemented in order to avoid scalability problems." INDEX {pintServerUserIdName, pintServerServiceTypeIndex, pintServerPerfStatPeriodIndex} ::= { pintServerUserIdStatsTable 1 }
pintServerUserIdName OBJECT-TYPE SYNTAX SnmpAdminString (SIZE(0..64)) MAX-ACCESS not-accessible STATUS current DESCRIPTION "The unique identifier of the monitored user identified by its name." ::= { pintServerUserIdStatsEntry 1 }
pintServerUserIdCallsReceived OBJECT-TYPE SYNTAX Counter32 MAX-ACCESS read-only STATUS current DESCRIPTION "Number of calls received from the specific user." ::= { pintServerUserIdStatsEntry 2 }
pintServerUserIdSuccessfulCalls OBJECT-TYPE SYNTAX Counter32 MAX-ACCESS read-only STATUS current DESCRIPTION "Number of calls from the user successfully completed." ::= { pintServerUserIdStatsEntry 3 }
pintServerUserIdDisconnectedCalls OBJECT-TYPE SYNTAX Counter32 MAX-ACCESS read-only STATUS current DESCRIPTION "Number of calls received from the user that were disconnected (failed)." ::= { pintServerUserIdStatsEntry 4 }
pintServerUserIdDiscUIdAFailCalls OBJECT-TYPE SYNTAX Counter32 MAX-ACCESS read-only STATUS current DESCRIPTION "Number of calls from the user that were disconnected because of user authorization failure." ::= { pintServerUserIdStatsEntry 5 }
pintServerUserIdEFProbCalls OBJECT-TYPE SYNTAX Counter32 MAX-ACCESS read-only STATUS current DESCRIPTION "Number of calls from the user that were disconnected because of egress facility problems." ::= { pintServerUserIdStatsEntry 6 }
pintServerGatewayStatsTable OBJECT-TYPE SYNTAX SEQUENCE OF PintServerGatewayStatsEntry MAX-ACCESS not-accessible STATUS current DESCRIPTION "Table displaying the monitored gateway statistics." ::= { pintServerGatewayPerf 1 }
pintServerGatewayStatsEntry OBJECT-TYPE SYNTAX PintServerGatewayStatsEntry MAX-ACCESS not-accessible STATUS current
DESCRIPTION "Entries in the gateway table. One entry is defined for each gateway identified by name, each monitored service type and performance statistics collection period."
pintServerGatewayCallsReceived OBJECT-TYPE SYNTAX Counter32 MAX-ACCESS read-only STATUS current DESCRIPTION "Number of calls received at the specified gateway." ::= { pintServerGatewayStatsEntry 1 }
pintServerGatewaySuccessfulCalls OBJECT-TYPE SYNTAX Counter32 MAX-ACCESS read-only STATUS current DESCRIPTION "Number of calls successfully completed at the specified gateway." ::= { pintServerGatewayStatsEntry 2 }
pintServerGatewayDisconnectedCalls OBJECT-TYPE SYNTAX Counter32 MAX-ACCESS read-only STATUS current DESCRIPTION "Number of calls that were disconnected (failed) at the specified gateway." ::= { pintServerGatewayStatsEntry 3 }
pintMibCompliance MODULE-COMPLIANCE STATUS current DESCRIPTION "Describes the requirements for conformance to the PINT MIB." MODULE -- this module MANDATORY-GROUPS { pintMibConfigGroup, pintMibMonitorGroup } ::= { pintMibCompliances 1 }
pintMibConfigGroup OBJECT-GROUP OBJECTS { pintReleaseNumber, pintSysContact, pintApplInstallPkgDescription, pintRegisteredGatewayName, pintRegisteredGatewayDescription } STATUS current DESCRIPTION "A collection of objects providing configuration information for a PINT Server." ::= { pintMibGroups 1 }
pintServerGatewayCallsReceived, pintServerGatewaySuccessfulCalls, pintServerGatewayDisconnectedCalls } STATUS current DESCRIPTION "A collection of objects providing monitoring information for a PINT Server." ::= { pintMibGroups 2 }
There is only one management object defined in this MIB that has a MAX-ACCESS clause of read-write (pintSysContact). There are no read-create objects. This read-write object 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.
There are a number of managed objects in this MIB that may contain information that may be sensitive from a business perspective. One could be the customer identification (UserIdName). Also information on PINT services performance might itself be need to be guarded. It is thus important to control even GET access to these objects and possibly to even encrypt the values of these object when sending them over the network via SNMP. Not all versions of SNMP provide features for such a secure environment.
SNMPv1 by itself is not a secure environment. 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.
It is recommended that the implementers consider the security features as provided by the SNMPv3 framework. Specifically, the use of the User-based Security Model RFC 2574 [13] and the View-based Access Control Model RFC 2575 [16] is recommended.
It is then a customer/user responsibility to ensure that the SNMP entity giving access to an instance of this MIB, 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.
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[1] Lu, H., Conroy, L., Bellovin, S., Krishnaswamy, M., Burg, F., DeSimone, A., Tewani, K., Davidson, P., Schulzrinne, H. and K. Vishwanathan, "Toward the PSTN/Internet Inter-Networking -- Pre-PINT Implementations", RFC 2458, November 1998.
[2] Wijnen, B., Harrington, D. and R. Presuhn, "An Architecture for Describing SNMP Management Frameworks", RFC 2571, April 1999.
[3] Rose, M. and K. McCloghrie, "Structure and Identification of Management Information for TCP/IP-based Internets", STD 16, RFC 1155, May 1990.
[4] Rose, M. and K. McCloghrie, "Concise MIB Definitions", STD 16, RFC 1212, March 1991.
[5] Rose, M., "A Convention for Defining Traps for use with the SNMP", RFC 1215, March 1991.
[6] McCloghrie, K., Perkins, D. and J. Schoenwaelder, "Structure of Management Information Version 2 (SMIv2)", STD 58, RFC 2578, April 1999.
[7] McCloghrie, K., Perkins, D. and J. Schoenwaelder, "Textual Conventions for SMIv2", STD 58, RFC 2579, April 1999.
[8] McCloghrie, K., Perkins, D. and J. Schoenwaelder, "Conformance Statements for SMIv2", STD 58, RFC 2580, April 1999.
[9] Case, J., Fedor, M., Schoffstall, M. and J. Davin, "Simple Network Management Protocol", STD 15, RFC 1157, May 1990.
[10] Case, J., McCloghrie, K., Rose, M. and S. Waldbusser, "Introduction to Community-based SNMPv2", RFC 1901, January 1996.
[11] Case, J., McCloghrie, K., Rose, M. and S. Waldbusser, "Transport Mappings for Version 2 of the Simple Network Management Protocol (SNMPv2)", RFC 1906, January 1996.
[12] Case, J., Harrington D., Presuhn R. and B. Wijnen, "Message Processing and Dispatching for the Simple Network Management Protocol (SNMP)", RFC 2572, April 1999.
[13] Blumenthal, U. and B. Wijnen, "User-based Security Model (USM) for version 3 of the Simple Network Management Protocol (SNMPv3)", RFC 2574, April 1999.
[14] Case, J., McCloghrie, K., Rose, M. and Waldbusser, "Protocol Operations for Version 2 of the Simple Network Management Protocol (SNMPv2)", RFC 1905, January 1996.
[15] Levi, D., Meyer, P. and B. Stewart, "SNMPv3 Applications", RFC 2573, April 1999.
[16] Wijnen, B., Presuhn, R. and K. McCloghrie, "View-based Access Control Model (VACM) for the Simple Network Management Protocol (SNMP)", RFC 2575, April 1999.
[17] Case, J., Mundy, R., Partain, D. and B. Stewart, "Introduction to Version 3 of the Internet-standard Network Management Framework", RFC 2570, April 1999.
[18] Petrack, S. and L. Conroy, "The PINT Service Protocol: Extensions to SIP and SDP for IP Access to Telephone Call Services", RFC 2848, June 2000.
[19] Krupczak, C. and J. Saperia, "Definitions of System-Level Managed Objects for Applications", RFC 2287, February 1998.
[20] Narten, T. and H. Alvestrand, "Guidelines for Writing an IANA Considerations Section in RFCs", BCP 26, RFC 2434, October 1998.
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