Network Working Group S. Chisholm Internet-Draft Nortel Intended status: Standards Track H. Trevino Expires: August 24, 2007 Cisco February 20, 2007 NETCONF Event Notifications draft-ietf-netconf-notification-06.txt Status of this Memo By submitting this Internet-Draft, each author represents that any applicable patent or other IPR claims of which he or she is aware have been or will be disclosed, and any of which he or she becomes aware will be disclosed, in accordance with Section 6 of BCP 79. Internet-Drafts are working documents of the Internet Engineering Task Force (IETF), its areas, and its working groups. Note that other groups may also distribute working documents as Internet- Drafts. Internet-Drafts are draft documents valid for a maximum of six months and may be updated, replaced, or obsoleted by other documents at any time. It is inappropriate to use Internet-Drafts as reference material or to cite them other than as "work in progress." The list of current Internet-Drafts can be accessed at http://www.ietf.org/ietf/1id-abstracts.txt. The list of Internet-Draft Shadow Directories can be accessed at http://www.ietf.org/shadow.html. This Internet-Draft will expire on August 24, 2007. Copyright Notice Copyright (C) The IETF Trust (2007). Chisholm & Trevino Expires August 24, 2007 [Page 1] Internet-Draft NETCONF Event Notifications February 2007 Abstract This document defines mechanisms which provide an asynchronous message notification delivery service for the NETCONF protocol. This is an optional capability built on top of the base NETCONF definition. This document defines the capabilities and operations necessary to support this service. Chisholm & Trevino Expires August 24, 2007 [Page 2] Internet-Draft NETCONF Event Notifications February 2007 Table of Contents 1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . . 4 1.1. Definition of Terms . . . . . . . . . . . . . . . . . . . 4 1.2. Event Notifications in NETCONF . . . . . . . . . . . . . . 5 1.3. Motivation . . . . . . . . . . . . . . . . . . . . . . . . 5 1.4. Requirements . . . . . . . . . . . . . . . . . . . . . . . 5 2. Notification-Related Operations . . . . . . . . . . . . . . . 7 2.1. Subscribing to receive Event Notifications . . . . . . . . 7 2.1.1. . . . . . . . . . . . . . . . . 7 2.2. Sending Event Notifications . . . . . . . . . . . . . . . 8 2.2.1. . . . . . . . . . . . . . . . . . . . . 8 2.3. Terminating the Subscription . . . . . . . . . . . . . . . 9 3. Supporting Concepts . . . . . . . . . . . . . . . . . . . . . 10 3.1. Capabilities Exchange . . . . . . . . . . . . . . . . . . 10 3.1.1. Capability Identifier . . . . . . . . . . . . . . . . 10 3.1.2. Capability Example . . . . . . . . . . . . . . . . . . 10 3.2. Event Streams . . . . . . . . . . . . . . . . . . . . . . 10 3.2.1. Event Stream Definition . . . . . . . . . . . . . . . 11 3.2.2. Event Stream Content Format . . . . . . . . . . . . . 11 3.2.3. Default Event Stream . . . . . . . . . . . . . . . . . 11 3.2.4. Event Stream Sources . . . . . . . . . . . . . . . . . 12 3.2.5. Event Stream Discovery . . . . . . . . . . . . . . . . 12 3.3. Notification Management Schema . . . . . . . . . . . . . . 13 3.4. Subscriptions not Configuration Data . . . . . . . . . . . 16 3.5. Filter Dependencies . . . . . . . . . . . . . . . . . . . 17 3.5.1. Named Profiles . . . . . . . . . . . . . . . . . . . . 17 3.5.2. Filtering . . . . . . . . . . . . . . . . . . . . . . 17 3.6. Message Flow . . . . . . . . . . . . . . . . . . . . . . . 17 4. XML Schema for Event Notifications . . . . . . . . . . . . . . 19 5. Filtering examples . . . . . . . . . . . . . . . . . . . . . . 22 5.1. Subtree Filtering . . . . . . . . . . . . . . . . . . . . 22 5.2. XPATH filters . . . . . . . . . . . . . . . . . . . . . . 25 6. Notification Replay . . . . . . . . . . . . . . . . . . . . . 27 6.1. Overview . . . . . . . . . . . . . . . . . . . . . . . . . 27 6.2. Creating a Subscription with Replay . . . . . . . . . . . 27 6.3. Replay Complete Notification . . . . . . . . . . . . . . . 28 7. Security Considerations . . . . . . . . . . . . . . . . . . . 30 8. Acknowledgements . . . . . . . . . . . . . . . . . . . . . . . 31 9. Normative References . . . . . . . . . . . . . . . . . . . . . 32 Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . . 33 Intellectual Property and Copyright Statements . . . . . . . . . . 34 Chisholm & Trevino Expires August 24, 2007 [Page 3] Internet-Draft NETCONF Event Notifications February 2007 1. Introduction [NETCONF] can be conceptually partitioned into four layers: Layer Example +-------------+ +----------------------------------------+ | Content | | Configuration data | +-------------+ +----------------------------------------+ | | +-------------+ +-------------------------------------------+ | Operations | | , | +-------------+ +-------------------------------------------+ | | | +-------------+ +-----------------------------+ | | RPC | | , | | +-------------+ +-----------------------------+ | | | | +-------------+ +------------------------------------------+ | Transport | | BEEP, SSH, SSL, console | | Protocol | | | +-------------+ +------------------------------------------+ This document defines mechanisms which provide an asynchronous message notification delivery service for the [NETCONF] protocol. This is an optional capability built on top of the base NETCONF definition. This memo defines the capabilities and operations necessary to support this service. Figure 1 1.1. Definition of Terms 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 [RFC2119]. Element: An [XML] Element. Managed Object: A collection of one of more Elements that define an abstract thing of interest. Subscription: A concept related to the delivery of notifications (if any to send) involving destination and selection of notifications. It is bound to the lifetime of a session. Chisholm & Trevino Expires August 24, 2007 [Page 4] Internet-Draft NETCONF Event Notifications February 2007 Operation: This term is used to refer to NETCONF protocol operations. Specifically within this document, operation refers to NETCONF protocol operations defined in support of NETCONF notifications. 1.2. Event Notifications in NETCONF An event is something that happens which may be of interest - a configuration change, a fault, a change in status, crossing a threshold, or an external input to the system, for example. Often this results in an asynchronous message, sometimes referred to as a notification or event notification, being sent out to interested parties to notify them that this event has occurred. This memo defines a mechanism whereby the NETCONF client indicates interest in receiving event notifications from a NETCONF server by creating a subscription to receive event notifications. The NETCONF server replies to indicate whether the subscription request was successful and, if it was successful, begins sending the event notifications to the NETCONF client as the events occur within the system. These event notifications will continue to be sent until either the NETCONF session is terminated or the subscription to terminate for some other reason. The event notification subscription allows a number of options to enable the NETCONF client to specify which events are of interest. These are specified when the subscription is created. An NETCONF server is not required to process RPC requests on the session associated with the subscription until the notification subscription is done and may silently discard these requests. A capability may be advertised to announce that a server is able to process RPCs while a notification stream is active on a session. 1.3. Motivation The motivation for this work is to enable the sending of asynchronous messages that are consistent with the data model (content) and security model used within a NETCONF implementation. 1.4. Requirements The following requirements have been addressed by the solution: o Initial release should ensure it supports notification in support of configuration operations o Data content must not preclude the use of the same data model as used in configuration Chisholm & Trevino Expires August 24, 2007 [Page 5] Internet-Draft NETCONF Event Notifications February 2007 o solution should support a reasonable message size limit (syslog and SNMP are rather constrained in terms of message sizes) o solution should provide reliable delivery of notifications o solution should provide a subscription mechanism (A NETCONF server does not send notifications before being asked to do so and the NETCONF client initiates the flow of notifications) o solution should provide a filtering mechanism within the NETCONF server o solution should send sufficient information in a notification so that it can be analyzed independent of the transport mechanism (data content fully describes a notification; protocol information is not needed to understand a notification) o solution should support replay of locally logged notifications Chisholm & Trevino Expires August 24, 2007 [Page 6] Internet-Draft NETCONF Event Notifications February 2007 2. Notification-Related Operations 2.1. Subscribing to receive Event Notifications The event notification subscription is initiated by the NETCONF client and responded to by the NETCONF server. When the event notification subscription is created, the events of interest are specified. Content for an event notification subscription can be selected by applying user-specified filters. 2.1.1. Description: This operation initiates an event notification subscription which will send asynchronous event notifications to the initiator of the command until the subscription to terminates. Parameters: Stream: An optional parameter that indicates which stream of events is of interest. If not present, then events in the default NETCONF stream will be sent. Filter: An optional parameter that indicates which subset of all possible events are of interest. The format of this parameter is the same as that of the filter parameter in the NETCONF protocol operations. If not present, all events not precluded by other parameters will be sent. This is mutually exclusive with the named profile parameter. Named Profile: An optional parameter that points to a separately defined filter profile. If not present, no additional filtering will be applied. Note that changes to the profile after the subscription has been created will have no effect. This is mutually exclusive with the filter parameter Chisholm & Trevino Expires August 24, 2007 [Page 7] Internet-Draft NETCONF Event Notifications February 2007 Start Time: A parameter used to trigger the replay feature and indicates that the replay should start at the time specified. If start time is not present, this is not a replay subscription. Stop Time: An optional parameter used with the optional replay feature to indicate the newest notifications of interest. If stop time is not present, the notifications will continue until the subscription is terminated. Must be used with 'startTime'. Positive Response: If the NETCONF server can satisfy the request, the server sends an element. Negative Response: An element is included within the if the request cannot be completed for any reason. Subscription requests will fail if a filter with invalid syntax is provided or if the name of a non-existent profile or stream is provided. 2.2. Sending Event Notifications Once the subscription has been set up, the NETCONF server sends the event notifications asynchronously along the connection. 2.2.1. Description: An event notification is sent to the initiator of a command asynchronously when an event of interest (i.e. meeting the specified filtering criteria) to them has occurred. An event notification is a complete and well-formed XML document. Note that is not an RPC method but rather the top level element identifying the one way message as a notification. Parameters: Chisholm & Trevino Expires August 24, 2007 [Page 8] Internet-Draft NETCONF Event Notifications February 2007 Data: Contains notification-specific tagged content. Response: No response. Not applicable. 2.3. Terminating the Subscription Closing of the event notification subscription can be done by terminating the NETCONF session ( ) or the underlying transport session. If a stop time is provided when the subscription is created, then the subscription will terminate after the stop time is reached. In this case, the Netconf session will still be an active session. Chisholm & Trevino Expires August 24, 2007 [Page 9] Internet-Draft NETCONF Event Notifications February 2007 3. Supporting Concepts 3.1. Capabilities Exchange The ability to process and send event notifications is advertised during the capability exchange between the NETCONF client and server. 3.1.1. Capability Identifier "urn:ietf:params:netconf:capability:notification:1.0" 3.1.2. Capability Example urn:ietf:params:xml:ns:netconf:base:1.0 urn:ietf:params:netconf:capability:startup:1.0 urn:ietf:params:netconf:capability:notification:1.0 4 3.2. Event Streams An event stream is defined herein as a set of event notifications matching some forwarding criteria. System components generate event notifications which are passed to a central component for classification and distribution. The central component inspects each event notification and matches the event notification against the set of stream definitions. When a match occurs, the event notification is considered to be a member of that event stream. An event notification may be part of multiple event streams. When a NETCONF client subscribes to a given event stream, user- defined filters, if applicable, are applied to the event stream and matching event notifications are forwarded to the NETCONF server for distribution to subscribed NETCONF clients. Chisholm & Trevino Expires August 24, 2007 [Page 10] Internet-Draft NETCONF Event Notifications February 2007 +----+ | c1 |---+ available streams +----+ | +---------+ +----+ | |central |-> stream 1 | c2 | +--->|event |-> stream 2 filter +-------+ +----+ | |processor|-> netconf stream --->|netconf| ... | | |-> stream n |server | see System | +---------+ +-------+ below Components| | // ... | | // +----+ | | (------------) | cn |---+ | (notification) +----+ +-----> ( logging ) ( service ) (------------) +-------+ +-------+ |netconf|<--->|netconf| -> |server | |client | +-------+ +-------+ 3.2.1. Event Stream Definition Event streams are predefined on the managed device. The configuration of event streams is outside the scope of this document. However, it is envisioned that event streams are either pre- established by the vendor (pre-configured) or user configurable (e.g. part of the device's configuration) or both. Device vendors may allow event stream configuration via NETCONF protocol (i.e. edit- config operation) 3.2.2. Event Stream Content Format The contents of all event streams made available to a NETCONF client (i.e. the notification sent by the NETCONF server) must be encoded in XML. 3.2.3. Default Event Stream A NETCONF server implementation supporting the notification capability must support the "NETCONF" notification event stream. This stream contains all NETCONF XML event notifications supported by the NETCONF server. The definition of the event notification and their contents for this event stream is outside the scope of this document. Chisholm & Trevino Expires August 24, 2007 [Page 11] Internet-Draft NETCONF Event Notifications February 2007 3.2.4. Event Stream Sources With the exception of the default event stream (NETCONF notifications) specification of additional event stream sources (e.g. SNMP, syslog, etc.) is outside the scope of this document. NETCONF server implementations may leverage any desired event stream source in the creation of supported event streams. 3.2.5. Event Stream Discovery A NETCONF client retrieves the list of supported event streams from a NETCONF server using the RPC request. 3.2.5.1. Name Retrieval using operation The list of available event streams is retrieved by requesting the subtree via a operation. Available event streams for the requesting session are returned in the reply containing the and elements, where element is mandatory and its value is unique. The returned list must only include the names of those event streams for which the NETCONF session has sufficient privileges. The NETCONF session privileges are determined via access control mechanisms which are beyond the scope of this document. An empty reply is returned if there are no available event streams. The information is retrieved by requesting the subtree via a operation. Example: Retrieving available event stream list using operation: Chisholm & Trevino Expires August 24, 2007 [Page 12] Internet-Draft NETCONF Event Notifications February 2007 The NETCONF server returns a list of event streams available for subscription: NETCONF, snmp, and syslog-critical in this example. NETCONF Default netconf event stream true snmp SNMP notifications false syslog-critical Critical and higher severity true 3.2.5.2. Event Stream Subscription A NETCONF client may request from the NETCONF server the list of available event streams to this session and then issue a request with the desired event stream name. Omitting the event stream name from the request results in subscription to the default NETCONF event stream. 3.2.5.2.1. Filtering Event Stream Contents The set of event notifications delivered in an event stream may be further refined by applying a user-specified filter at subscription creation time ( ). This is a transient filter associated with the event notification subscription and does not modify the event stream configuration. 3.3. Notification Management Schema Chisholm & Trevino Expires August 24, 2007 [Page 13] Internet-Draft NETCONF Event Notifications February 2007 A schema that can be used to learn about current event streams and to manage named profiles. The list of event streams supported by the system. When a query is issued, the returned set of streams is determined based on user privileges Stream name and description Chisholm & Trevino Expires August 24, 2007 [Page 14] Internet-Draft NETCONF Event Notifications February 2007 A named profile, which is a saved set of parameters associated that may be associated with zero or more active subscriptions. This object can be created, read, deleted and its individual components can be modified. The name associated with the profile. This object is readable and modifiable. The event stream associated with this named profile. This object is readable and modifiable. The filters associated with this named profile. Chisholm & Trevino Expires August 24, 2007 [Page 15] Internet-Draft NETCONF Event Notifications February 2007 This object is readable and modifiable. The timestamp of the last modification to this named Profile. Note that modification of the profile does not cause an immediate update to all applicable subscription. Therefore, this time should be compared with the last modified time associated with the subscription. If this time is earlier, then the subscription is using the exact set of parameters associated with this named profile. If this time is later, then the subscription is using an earlier version of this named profile and the exact parameters may not match. This object is read-only. 3.4. Subscriptions not Configuration Data While it may be possible to retrieve information about subscriptions via a get operation, subscriptions are not stored configuration. They are non-persistent state information. In this respect, they are comparable to NETCONF sessions. Chisholm & Trevino Expires August 24, 2007 [Page 16] Internet-Draft NETCONF Event Notifications February 2007 Named profiles, if used, are considered configuration data. 3.5. Filter Dependencies Note that when multiple filters are specified, they are applied collectively, so event notifications need to pass all specified filters in order to be sent to the subscriber. If a filter is specified to look for data of a particular value, and the data item is not present within a particular event notification for its value to be checked against, it will be filtered out. For example, if one were to check for 'severity=critical' in a configuration event notification where this field was not supported, then the notification would be filtered out. Note that the order that filters are applied does not matter since the resulting set of notifications is the intersection of the set of notifications that pass each filtering criteria. 3.5.1. Named Profiles A named profile is a filter that is created ahead of time and applied at the time an event notification subscription is created . Note that changes to the profile after the subscription has been created will have no effect on the subscription. Since named profiles exist outside of the subscription, they persist after the subscription has been torn down. 3.5.2. Filtering Just-in-time filtering is explicitly stated when the event notification subscription is created. This is specified via the 'filter' parameter. Filters only exist as parameters to the subscription. 3.6. Message Flow Chisholm & Trevino Expires August 24, 2007 [Page 17] Internet-Draft NETCONF Event Notifications February 2007 The following figure depicts message flow between a NETCONF client (C) and NETCONF server (S) in order create a subscription and begin the flow of notifications. C S | | | capability exchange | |-------------------------->| |<------------------------->| | | | | |-------------------------->| |<--------------------------| | | | | | | |<--------------------------| | | | | |<--------------------------| | | | | | | | | |<--------------------------| | | | | Chisholm & Trevino Expires August 24, 2007 [Page 18] Internet-Draft NETCONF Event Notifications February 2007 4. XML Schema for Event Notifications The following [XML Schema] defines Netconf Event Notifications. This import accesses the xml: attribute groups for the xml:lang as declared on the error-message element. An optional parameter that indicates which stream of events is of interest. If not present, then events in the default NETCONF stream will be sent. Chisholm & Trevino Expires August 24, 2007 [Page 19] Internet-Draft NETCONF Event Notifications February 2007 An optional parameter that indicates which subset of all possible events are of interest. The format of this parameter is the same as that of the filter parameter in the NETCONF protocol operations. If not present, all events not precluded by other parameters will be sent. This is mutually exclusive with the named profile parameter. An optional parameter that points to a separately defined filter profile. If not present, no additional filtering will be applied. Note that changes to the profile after the subscription has been created will have no effect. This is mutually exclusive with the filter parameter A parameter used to trigger the replay feature and indicates that the replay should start at the time specified. If start time is not present, this is not a replay subscription. An optional parameter used with the optional replay feature to indicate the newest notifications of Chisholm & Trevino Expires August 24, 2007 [Page 20] Internet-Draft NETCONF Event Notifications February 2007 interest. If stop time is not present, the notifications will continue until the subscription is terminated. Must be used with 'startTime'. The command to create a notification subscription. It takes as argument the name of the notification stream and filter or profile information. All of those options limit the content of the subscription. In addition, there are two time-related parameters startTime and stopTime which can be used to select the time interval of interest. Chisholm & Trevino Expires August 24, 2007 [Page 21] Internet-Draft NETCONF Event Notifications February 2007 5. Filtering examples The following section provides examples to illustrate the various methods of filtering content on an event notification subscription. 5.1. Subtree Filtering XML subtree filtering is not well suited for creating elaborate filter definitions given that it only supports equality comparisons and logical OR operations (e.g. in an event subtree give me all event notifications which have severity=critical or severity=major or severity=minor). Nevertheless, it may be used for defining simple event notification forwarding filters as shown below. In order to illustrate the use of filter expressions it is necessary to assume some of the event notification content. The examples herein assume that the event notification schema definition has an element at the top level that contains one or more child elements consisting of the event class (e.g. fault, state, config, etc.) reporting entity and either severity or operational state. Chisholm & Trevino Expires August 24, 2007 [Page 22] Internet-Draft NETCONF Event Notifications February 2007 Sample event list fault Ethernet0 major fault Ethernet2 critical fault ATM1 minor state Ethernet0 enabled The following example illustrates selecting events which have severities of critical, major, or minor (presumably fault events). The filtering criteria evaluation is as follows: ((severity=critical) | (severity=major) | (severity=minor)) Chisholm & Trevino Expires August 24, 2007 [Page 23] Internet-Draft NETCONF Event Notifications February 2007 critical major minor The following example illustrates selecting state or config EventClasses or fault events that are related to card Ethernet0. The filtering criteria evaluation is as follows: ( state | config | fault & card=Ethernet0) Chisholm & Trevino Expires August 24, 2007 [Page 24] Internet-Draft NETCONF Event Notifications February 2007 xmlns="urn:ietf:params:xml:ns:netconf:notification:1.0"> fault state config fault Ethernet0 5.2. XPATH filters The following [XPATH] example illustrates selecting fault EventClass notifications that have severities of critical, major, or minor. The filtering criteria evaluation is as follows: ((fault) & ((severity=critical) | (severity=major) | (severity = minor))) Chisholm & Trevino Expires August 24, 2007 [Page 25] Internet-Draft NETCONF Event Notifications February 2007 The following example illustrates selecting state and config EventClasses or fault events that have severities of critical, major, or minor or come from card Ethernet0. The filtering criteria evaluation is as follows: (( state | config) & ((fault & severity=critical) | (fault & severity=major) | (fault & severity = minor) | (fault & card=Ethernet0))) Chisholm & Trevino Expires August 24, 2007 [Page 26] Internet-Draft NETCONF Event Notifications February 2007 6. Notification Replay 6.1. Overview Replay is the ability to create an event subscription that will resend recently sent notifications. These notifications are sent the same way as normal notifications. A replay of notifications is specified by including an optional parameter to the subscription command that indicates the start time of the replay. The end time is specified using the optional stopTime parameter. If not present, notifications will continue to be sent until the subscription is terminated. A notification stream that supports replay is not expected to have an unlimited supply of saved notifications available to accommodate any replay request. If a client requests a replay of notifications that predate the oldest notification available, then the NETCONF server must return a warning message in the RPC reply and start replaying the notifications it does have available, within the other constraints, such as filtering, that the client has provided. The warning message enables the NETCONF client to differentiate between the case that there were no notifications generated within a given time period from the case that no notifications are currently in the log from that period. The actual number of stored notifications available for retrieval at any given time is an NETCONF server implementation specific matter. Control parameters for this aspect of the feature are outside the scope of the current work. This feature is dependent on a notification stream supporting some form of notification logging, although it puts no restrictions on the size or form of the log, nor where it resides within the device. 6.2. Creating a Subscription with Replay This feature uses optional parameters to the command called 'startTime' and 'stopTime'. 'startTime' identifies the earliest date and time of interest for event notifications being replayed and also indicates that a subscription will be providing replay of notifications. Events generated before this time are not matched. 'stopTime' specifies the latest date and time of interest for event notifications being replayed. If it is not present, then notifications will continue to be sent until the subscription is terminated. Note that while a notification has three potential times associated Chisholm & Trevino Expires August 24, 2007 [Page 27] Internet-Draft NETCONF Event Notifications February 2007 it - the time it was generated, the time it was logged and the time it was sent out by the NETCONF server - the startTime and stopTime parameters are related to generation time. In the event of an error with severity of warning, the subscription will still be created. Negative Response: An element is included in the if the startTime in replay request predates the oldest notification available to be replayed or if the stopTime is earlier then the startTime. Error-tag: start-time-too-early Error-type: protocol Error-severity: warning Error-info: : Timestamp of earliest event available for replay Error-message: Start time predates oldest available notification to be replayed Error-tag: start-stop-time-mismatch Error-type: protocol Error-severity: error Error-info: none Error-message: stopTime predates startTime. 6.3. Replay Complete Notification The following notification is the last notification sent over a replay subscription. It indicates that replay is complete. This notification will only be sent if a 'stopTime' was specified when the replay subscription was created. After this notification is received the subscription is terminated and the session becomes a normal Netconf session. The replayCompleteNotifcation can not be filtered out. It will always be sent on a relay subscription that specified a stop time. Chisholm & Trevino Expires August 24, 2007 [Page 28] Internet-Draft NETCONF Event Notifications February 2007 This notification is sent to signal the end of a replay subscription. The event classification of this notification. Chisholm & Trevino Expires August 24, 2007 [Page 29] Internet-Draft NETCONF Event Notifications February 2007 7. Security Considerations The security considerations from the base [NETCONF] document apply also to the Notification capability. The access control framework and the choice of transport will have a major impact on the security of the solution. Note that the elements are never sent before the transport layer and the netconf layer (capabilities exchange) have been established, and the manager has been identified and authenticated. It is recommended that care be taken to ensure the secure operation of the following commands: o invocation o use of o read-only data models o read-write data models o notification content One issue related to the notifications draft is the transport of data from non-netconf streams, such as syslog and SNMP. Note that this data may be more vulnerable (or is not more vulnerable) when being transported over netconf than when being transported using the protocol normally used for transporting it, depending on the security credentials of the two subsystems. Chisholm & Trevino Expires August 24, 2007 [Page 30] Internet-Draft NETCONF Event Notifications February 2007 8. Acknowledgements Thanks to Gilbert Gagnon, Greg Wilbur and Kim Curran for providing their input into the early work on this document. In addition, the editors would like to acknowledge input at the Vancouver editing session from the following people: Orly Nicklass, James Balestriere, Yoshifumi Atarashi, Glenn Waters, Alexander Clemm, Dave Harrington, Dave Partain, Ray Atarashi and Dave Perkins and the following additional people from the Montreal editing session: Balazs Lengyel, Phil Shafer, Rob Ennes, Andy Bierman, Dan Romascanu, Bert Wijnen, Simon Leinen, Juergen Schoenwaelder, Hideki Okita, Vincent Cridlig, Martin Bjorklund, Olivier Festor, Radu State, Brian Trammell, William Chow. Chisholm & Trevino Expires August 24, 2007 [Page 31] Internet-Draft NETCONF Event Notifications February 2007 9. Normative References [NETCONF] Enns, R., "NETCONF Configuration Protocol", ID draft-ietf-netconf-prot-12, February 2006. [RFC2026] Bradner, S., "The Internet Standards Process -- Revision 3", RFC 2026, BCP 9, October 1996. [RFC2119] Bradner, s., "Key words for RFCs to Indicate Requirements Levels", RFC 2119, March 1997. [RFC2223] Postel, J. and J. Reynolds, "Instructions to RFC Authors", RFC 2223, October 1997. [XML] World Wide Web Consortium, "Extensible Markup Language (XML) 1.0", W3C XML, February 1998, . [XML Schema] Fallside, D. and P. Walmsley, "XML Schema Part 0: Primer Second Edition", W3C XML Schema, October 2004. [XPATH] Clark, J. and S. DeRose, "XML Path Language (XPath) Version 1.0", W3C http://www.w3.org/TR/1999/REC-xpath-19991116, November 1999. Chisholm & Trevino Expires August 24, 2007 [Page 32] Internet-Draft NETCONF Event Notifications February 2007 Authors' Addresses Sharon Chisholm Nortel 3500 Carling Ave Nepean, Ontario K2H 8E9 Canada Email: schishol@nortel.com Hector Trevino Cisco Suite 400 9155 E. Nichols Ave Englewood, CO 80112 USA Email: htrevino@cisco.com Chisholm & Trevino Expires August 24, 2007 [Page 33] Internet-Draft NETCONF Event Notifications February 2007 Full Copyright Statement Copyright (C) The IETF Trust (2007). 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The IETF invites any interested party to bring to its attention any copyrights, patents or patent applications, or other proprietary rights that may cover technology that may be required to implement this standard. Please address the information to the IETF at ietf-ipr@ietf.org. Acknowledgment Funding for the RFC Editor function is provided by the IETF Administrative Support Activity (IASA). Chisholm & Trevino Expires August 24, 2007 [Page 34]