GENWiki

Premier IT Outsourcing and Support Services within the UK

User Tools

Site Tools


rfc:rfc3914

Network Working Group A. Barbir Request for Comments: 3914 Nortel Networks Category: Informational A. Rousskov

                                               The Measurement Factory
                                                          October 2004
         Open Pluggable Edge Services (OPES) Treatment of
                         IAB Considerations

Status of this Memo

 This memo provides information for the Internet community.  It does
 not specify an Internet standard of any kind.  Distribution of this
 memo is unlimited.

Copyright Notice

 Copyright (C) The Internet Society (2004).

Abstract

 IETF Internet Architecture Board (IAB) expressed nine architecture-
 level considerations for the Open Pluggable Edge Services (OPES)
 framework.  This document describes how OPES addresses those
 considerations.

Babir & Rousskov Informational [Page 1] RFC 3914 OPES Treatment of IAB Considerations October 2004

Table of Contents

 1.  Introduction . . . . . . . . . . . . . . . . . . . . . . . . .  2
 2.  Terminology  . . . . . . . . . . . . . . . . . . . . . . . . .  3
 3.  Consideration (2.1) 'One-party consent'  . . . . . . . . . . .  3
 4.  Consideration (2.2) 'IP-layer communications'  . . . . . . . .  4
 5.  Notification Considerations  . . . . . . . . . . . . . . . . .  5
     5.1.  Notification versus trace. . . . . . . . . . . . . . . .  6
     5.2.  An example of an OPES trace for HTTP . . . . . . . . . .  8
     5.3.  Consideration (3.1) 'Notification' . . . . . . . . . . .  9
     5.4.  Consideration (3.2) 'Notification' . . . . . . . . . . . 10
 6.  Consideration (3.3) 'Non-blocking' . . . . . . . . . . . . . . 10
 7.  Consideration (4.1) 'URI resolution' . . . . . . . . . . . . . 11
 8.  Consideration (4.2) 'Reference validity' . . . . . . . . . . . 11
 9.  Consideration (4.3) 'Addressing extensions'  . . . . . . . . . 12
 10. Consideration (5.1) 'Privacy'  . . . . . . . . . . . . . . . . 12
 11. Consideration 'Encryption' . . . . . . . . . . . . . . . . . . 12
 12. Security Considerations  . . . . . . . . . . . . . . . . . . . 13
 13. Compliance . . . . . . . . . . . . . . . . . . . . . . . . . . 13
 14. References . . . . . . . . . . . . . . . . . . . . . . . . . . 14
     14.1. Normative References . . . . . . . . . . . . . . . . . . 14
     14.2. Informative References . . . . . . . . . . . . . . . . . 14
 Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . . 15
 Full Copyright Statement . . . . . . . . . . . . . . . . . . . . . 16

1. Introduction

 The Open Pluggable Edge Services (OPES) architecture [RFC3835],
 enables cooperative application services (OPES services) between a
 data provider, a data consumer, and zero or more OPES processors.
 The application services under consideration analyze and possibly
 transform application-level messages exchanged between the data
 provider and the data consumer.
 In the process of chartering OPES, the IAB made recommendations on
 issues that OPES solutions should be required to address.  These
 recommendations were formulated in the form of a specific IAB
 considerations document [RFC3238].  In that document, IAB emphasized
 that its considerations did not recommend specific solutions and did
 not mandate specific functional requirements.  Addressing an IAB
 consideration may involve showing appropriate protocol mechanisms or
 demonstrating that the issue does not apply.  Addressing a
 consideration does not necessarily mean supporting technology implied
 by the consideration wording.

Babir & Rousskov Informational [Page 2] RFC 3914 OPES Treatment of IAB Considerations October 2004

 The primary goal of this document is to show that all formal IAB
 recommendations are addressed by OPES, to the extent that those
 considerations can be addressed by an IETF working group.  The
 limitations of OPES working group to address certain aspects of IAB
 considerations are also explicitly documented.
 IAB considerations document [RFC3238] contains many informal
 recommendations.  For example, while the IAB informally requires OPES
 architecture to "protect end-to-end data integrity by supporting
 end-host detection and response to inappropriate behavior by OPES
 intermediaries", the IAB has chosen to formalize these requirements
 via a set of more specific recommendations, such as Notification
 considerations addressed in Section 5.3 and Section 5.4 below.  OPES
 framework addresses informal IAB recommendations by addressing
 corresponding formal considerations.
 There are nine formal IAB considerations [RFC3238] that OPES has to
 address.  In the core of this document are the corresponding nine
 "Consideration" sections.  For each IAB consideration, its section
 contains general discussion as well as references to specific OPES
 mechanisms relevant to the consideration.

2. Terminology

 This document does not introduce any new terminology but uses
 terminology from other OPES documents.

3. Consideration (2.1) 'One-party consent'

 "An OPES framework standardized in the IETF must require that the use
 of any OPES service be explicitly authorized by one of the
 application-layer end-hosts (that is, either the content provider or
 the client)." [RFC3238]
 OPES architecture requires that "OPES processors MUST be consented to
 by either the data consumer or data provider application" [RFC3835].
 While this requirement directly satisfies IAB concern, no requirement
 alone can prevent consent-less introduction of OPES processors.  In
 other words, OPES framework requires one-party consent but cannot
 guarantee it in the presence of incompliant OPES entities.
 In [RFC3897], the OPES architecture enables concerned parties to
 detect unwanted OPES processors by examining OPES traces.  While the
 use of traces in OPES is mandatory, a tracing mechanism on its own
 cannot detect processors that are in violation of OPES
 specifications.  Examples include OPES processors operating in
 stealth mode.  However, the OPES architecture allows the use of
 content signature to verify the authenticity of performed

Babir & Rousskov Informational [Page 3] RFC 3914 OPES Treatment of IAB Considerations October 2004

 adaptations.  Content signatures is a strong but expensive mechanism
 that can detect any modifications of signed content provided that the
 content provider is willing to sign the data and that the client is
 willing to either check the signature or relay received content to
 the content provider for signature verification.
 OPES entities may copy or otherwise access content without modifying
 it.  Such access cannot be detected using content signatures.  Thus,
 "passive" OPES entities can operate on signed content without the
 data consumer or provider consent.  If content privacy is a concern,
 then content encryption can be used.  A passive processor is no
 different from any intermediary operating outside of OPES framework.
 No OPES mechanism (existing or foreseeable) can prevent non-modifying
 access to content.
 In summary, the one-party consent is satisfied by including the
 corresponding requirement in the IAB architecture document.  That
 requirement alone cannot stop incompliant OPES entities to perform
 consent-less adaptations, but OPES framework allows for various means
 of detecting and/or preventing such adaptations.  These means
 typically introduce overheads and require some level of producer-
 consumer cooperation.

4. Consideration (2.2) 'IP-layer communications'

 "For an OPES framework standardized in the IETF, the OPES
 intermediary must be explicitly addressed at the IP layer by the end
 user" [RFC3238].
 The OPES architecture requires that "OPES processors MUST be
 addressable at the IP layer by the end user (data consumer
 application)" [RFC3835].  The IAB and the architecture documents
 mention an important exception: addressing the first OPES processor
 in a chain of processors is sufficient.  That is, a chain of OPES
 processors is viewed as a single OPES "system" at the address of the
 first chain element.
 The notion of a chain is not strictly defined by IAB.  For the
 purpose of addressing this consideration, a group of OPES processors
 working on a given application transaction is considered.  Such a
 group would necessarily form a single processing chain, with a single
 "exit" OPES processor (i.e., the processor that adapted the given
 message last).  The OPES architecture essentially requires that last
 OPES processor to be explicitly addressable at the IP layer by the
 data consumer application.  The chain formation, including its exit
 point may depend on an application message and other dynamic factors
 such as time of the day or system load.

Babir & Rousskov Informational [Page 4] RFC 3914 OPES Treatment of IAB Considerations October 2004

 Furthermore, if OPES processing is an internal processing step at a
 data consumer or a data provider application side, then the last OPES
 processor may reside in a private address space and may not be
 explicitly addressable from the outside.  In such situations, the
 processing side must designate an addressable point on the same
 processing chain.  That designated point may not be, strictly
 speaking, an OPES processor, but it will suffice as such as far as
 IAB considerations are concerned -- the data consumer application
 will be able to address it explicitly at the IP layer and it will
 represent the OPES processing chain to the outside world.
 Designating an addressable processing point avoids the conflict
 between narrow interpretation of the IAB consideration and real
 system designs.  It is irrational to expect a content provider to
 provide access to internal hosts participating in content generation,
 whether OPES processors are involved or not.  Moreover, providing
 such access would serve little practical purpose because internal
 OPES processors are not likely to be able to answer any data consumer
 queries, being completely out of content generation context.  For
 example, an OPES processor adding customer-specific information to
 XML pages may not understand or be aware of any final HTML content
 that the data consumer application receives and may not be able to
 map end user request to any internal user identification.  Since OPES
 requires the end of the message processing chain to be addressable,
 the conflict does not exist.  OPES places no requirements on the
 internal architecture of data producer systems while requiring the
 entire OPES-related content production "system" to be addressable at
 the IP layer.
 Private Domain    | Public Domain     | Private Domain
                   |                   |
 +--------------+  |             +-------------+      +--------+
 | Data         |  |             | OPES System |      |Data    |
 | Consumer     |<--- network -->| with public |<---->|Provider|
 | Application  |  |             | IP address  |      |App     |
 +--------------+  |             +-------------+      +--------+
                   |                   |
                   |                   |
                              Figure 1

5. Notification Considerations

 This section discusses how OPES framework addresses IAB Notification
 considerations 3.1 and 3.2.

Babir & Rousskov Informational [Page 5] RFC 3914 OPES Treatment of IAB Considerations October 2004

5.1. Notification versus trace

 Before specific considerations are discussed, the relationship
 between IAB notifications and OPES tracing has to be explained.  OPES
 framework concentrates on tracing rather than notification.  The OPES
 Communications specification [RFC3897] defines "OPES trace" as
 application message information about OPES entities that adapted the
 message.  Thus, OPES trace follows the application message it traces.
 The trace is for the recipient of the application message.  Traces
 are implemented as extensions of application protocols being adapted
 and traced.
 As opposed to an OPES trace, provider notification (as implied by
 IAB) notifies the sender of the application message rather than the
 recipient.  Thus, notifications propagate in the opposite direction
 of traces.  Supporting notifications directly would require a new
 protocol.  Figure 2 illustrates the differences between a trace and
 notification from a single application message point of view.
 sender --[message A]--> OPES --[message A']--> recipient
    ^                       V                             [with trace]
    |                       |
    +-<-- [notification] ---+
                              Figure 2
 Since notifications cannot be piggy-backed to application messages,
 they create new messages and may double the number of messages the
 sender has to process.  The number of messages that need to be
 proceed is larger if several intermediaries on the message path
 generate notifications.  Associating notifications with application
 messages may require duplicating application message information in
 notifications and may require maintaining a sender state until
 notification is received.  These actions increase the performance
 overhead of notifications.
 The level of available details in notifications versus provider
 interest in supporting notification is another concern.  Experience
 shows that content providers often require very detailed information
 about user actions to be interested in notifications at all.  For
 example, Hit Metering protocol [RFC2227] has been designed to supply
 content providers with proxy cache hit counts, in an effort to reduce
 cache busting behavior which was caused by content providers desire
 to get accurate site "access counts".  However, the Hit Metering
 protocol is currently not widely deployed because the protocol does
 not supply content providers with information such as client IP
 addresses, browser versions, or cookies.

Babir & Rousskov Informational [Page 6] RFC 3914 OPES Treatment of IAB Considerations October 2004

 Hit Metering experience is relevant because Hit Metering protocol was
 designed to do for HTTP caching intermediaries what OPES
 notifications are meant to do for OPES intermediaries.  Performance
 requirements call for state reduction via aggregation of
 notifications while provider preferences call for state preservation
 or duplication.  Achieving the right balance when two sides belong to
 different organizations and have different optimization priorities
 may be impossible.
 Thus, instead of explicitly supporting notifications at the protocol
 level, OPES concentrates on tracing facilities.  In essence, OPES
 supports notifications indirectly, using tracing facilities.  In
 other words, the IAB choice of "Notification" label is interpreted as
 "Notification assistance" (i.e., making notifications meaningful) and
 is not interpreted as a "Notification protocol".
 The above concerns call for making notification optional.  The OPES
 architecture allows for an efficient and meaningful notification
 protocol to be implemented in certain OPES environments.  For
 example, an OPES callout server attached to a gateway or firewall may
 scan outgoing traffic for signs of worm or virus activity and notify
 a local Intrusion Detection System (IDS) of potentially compromised
 hosts (e.g., servers or client PCs) inside the network.  Such
 notifications may use OPES tracing information to pinpoint the
 infected host (which could be another OPES entity).  In this example,
 notifications are essentially sent back to the content producer (the
 local network) and use OPES tracing to supply details.
 Another environment where efficient and meaningful notification using
 OPES tracing is possible are Content Delivery Networks (CDNs).  A CDN
 node may use multiple content adaptation services to customize
 generic content supplied by the content producer (a web site).  For
 example, a callout service may insert advertisements for client-local
 events.  The CDN node itself may not understand specifics of the ad
 insertion algorithm implemented at callout servers.  However, the
 node may use information in the OPES trace (e.g., coming from the
 callout service) to notify the content producer.  Such notifications
 may be about the number of certain advertisements inserted (i.e., the
 number of "impressions" delivered to the customer) or even the number
 of ad "clicks" the customer made (e.g., if the node hosts content
 linked from the ads).  Callout services doing ad insertion may lack
 details (e.g., a customer ID/address or a web server authentication
 token) to contact the content producer directly in this case.  Thus,
 OPES trace produced by an OPES service becomes essential in enabling
 meaningful notifications that the CDN node sends to the content
 producer.

Babir & Rousskov Informational [Page 7] RFC 3914 OPES Treatment of IAB Considerations October 2004

5.2. An example of an OPES trace for HTTP

 The example below illustrates adaptations done to HTTP request at an
 OPES processor operated by the client ISP.  Both original (as sent by
 an end user) and adapted (as received by the origin web server)
 requests are shown.  The primary adaptation is the modification of
 HTTP "Accept" header.  The secondary adaptation is the addition of an
 OPES-System HTTP extension header [I-D.ietf-opes-http].
 GET /pub/WWW/ HTTP/1.1
 Host: www.w3.org
 Accept: text/plain
                              Figure 3
 ... may be adapted by an ISP OPES system to become:
 GET /pub/WWW/ HTTP/1.1
 Host: www.w3.org
 Accept: text/plain; q=0.5, text/html, text/x-dvi; q=0.8
 OPES-System: http://www.isp-example.com/opes/?client-hash=1234567
                              Figure 4
 The example below illustrates adaptations done to HTTP response at an
 OPES intermediary operated by a Content Distribution Network (CDN).
 Both original (as sent by the origin web server) and adapted (as
 received by the end user) responses are shown.  The primary
 adaptation is the conversion from HTML markup to plain text.  The
 secondary adaptation is the addition of an OPES-System HTTP extension
 header.
 HTTP/1.1 200 OK
 Content-Length: 12345
 Content-Encoding: text/html
 <html><head><h1>Available Documenta...
                              Figure 5
 ... may be adapted by a CDN OPES system to become:
 HTTP/1.1 200 OK
 Content-Length: 2345
 Content-Encoding: text/plain
 OPES-System: http://www.cdn-example.com/opes/?site=7654&svc=h2t
 AVAILABLE DOCUMENTA...
                              Figure 6

Babir & Rousskov Informational [Page 8] RFC 3914 OPES Treatment of IAB Considerations October 2004

 In the above examples, OPES-System header values contain URIs that
 may point to OPES-specific documents such as description of the OPES
 operator and its privacy policy.  Those documents may be
 parameterized to allow for customizations specific to the transaction
 being traced (e.g., client or even transaction identifier may be used
 to provide more information about performed adaptations).  An OPES-
 Via header may be used to provide a more detailed trace of specific
 OPES entities within an OPES System that adapted the message.  Traced
 OPES URIs may be later used to request OPES bypass [RFC3897].

5.3. Consideration (3.1) 'Notification'

 "The overall OPES framework needs to assist content providers in
 detecting and responding to client-centric actions by OPES
 intermediaries that are deemed inappropriate by the content provider"
 [RFC3238].
 OPES tracing mechanisms assist content providers in detecting
 client-centric actions by OPES intermediaries.  Specifically, a
 compliant OPES intermediary or system notifies a content provider of
 its presence by including its tracing information in the application
 protocol requests.  An OPES system MUST leave its trace [RFC3897].
 Detection assistance has its limitations.  Some OPES intermediaries
 may work exclusively on responses and may not have a chance to trace
 the request.  Moreover, some application protocols may not have
 explicit requests (e.g., a content push service).
 OPES tracing mechanisms assist content providers in responding to
 client-centric actions by OPES intermediaries.  Specifically, OPES
 traces MUST include identification of OPES systems and SHOULD include
 a list of adaptation actions performed on provider's content.  This
 tracing information may be included in the application request.
 Usually, however, this information will be included in the
 application response, an adapted version of which does not reach the
 content provider.  If OPES end points cooperate, then notification
 can be assisted with traces.  Content providers that suspect or
 experience difficulties can do any of the following:
 o  Check whether requests they receive pass through OPES
    intermediaries.  Presence of OPES tracing info will determine
    that.  This check is only possible for request/response protocols.
    For other protocols (e.g., broadcast or push), the provider would
    have to assume that OPES intermediaries are involved until proven
    otherwise.

Babir & Rousskov Informational [Page 9] RFC 3914 OPES Treatment of IAB Considerations October 2004

 o  If OPES intermediaries are suspected, request OPES traces from
    potentially affected user(s).  The trace will be a part of the
    application message received by the user software.  If involved
    parties cooperate, the provider(s) may have access to all the
    needed information.  Certainly, lack of cooperation may hinder
    access to tracing information.  To encourage cooperation, data
    providers might be able to deny service to uncooperative users.
 o  Some traces may indicate that more information is available by
    accessing certain resources on the specified OPES intermediary or
    elsewhere.  Content providers may query for more information in
    this case.
 o  If everything else fails, providers can enforce no-adaptation
    policy using appropriate OPES bypass mechanisms and/or end-to-end
    encryption mechanisms.
 OPES detection and response assistance is limited to application
 protocols with support for tracing extensions.  For example, HTTP
 [RFC2616] has such support while DNS over UDP does not.

5.4. Consideration (3.2) 'Notification'

 "The overall OPES framework should assist end users in detecting the
 behavior of OPES intermediaries, potentially allowing them to
 identify imperfect or compromised intermediaries" [RFC3238].
 OPES tracing mechanisms assist end users in detecting OPES
 intermediaries.  Specifically, a compliant OPES intermediary or
 system notifies an end user of its presence by including its tracing
 information in the application protocol messages sent to the client.
 An OPES system MUST leave its trace [RFC3897].  However, detection
 assistance has its limitations.  Some OPES systems may work
 exclusively on requests and may not have a chance to trace the
 response.  Moreover, some application protocols may not have explicit
 responses (e.g., event logging service).
 OPES detection assistance is limited to application protocols with
 support for tracing extensions.  For example, HTTP [RFC2616] has such
 support while DNS over UDP does not.

6. Consideration (3.3) 'Non-blocking'

 "If there exists a "non-OPES" version of content available from the
 content provider, the OPES architecture must not prevent users from
 retrieving this "non-OPES" version from the content provider"
 [RFC3238].

Babir & Rousskov Informational [Page 10] RFC 3914 OPES Treatment of IAB Considerations October 2004

 "OPES entities MUST support a bypass feature" [RFC3897].  If an
 application message includes bypass instructions and an OPES
 intermediary is not configured to ignore them, the matching OPES
 intermediary will not process the message.  An OPES intermediary may
 be configured to ignore bypass instructions only if no non-OPES
 version of content is available.  Bypass may generate content errors
 since some OPES services may be essential but may not be configured
 as such.
 Bypass support has limitations similar to the two notification-
 related considerations above.

7. Consideration (4.1) 'URI resolution'

 "OPES documentation must be clear in describing these services as
 being applied to the result of URI resolution, not as URI resolution
 itself" [RFC3238].
 "OPES Scenarios and Use Cases" specification [RFC3752] documents
 content adaptations that are in scope of the OPES framework.
 Scenarios include content adaptation of requests and responses.
 These documented adaptations do not include URI resolution.  In some
 environments, it is technically possible to use documented OPES
 mechanisms to resolve URIs (and other kinds of identifiers or
 addresses).  The OPES framework cannot effectively prevent any
 specific kind of adaptation.
 For example, a CDN node may substitute domain names in URLs with
 CDN-chosen IP addresses, essentially performing a URI resolution on
 behalf of the content producer (i.e., the web site owner).  An OPES
 callout service running on a user PC may rewrite all HTML-embedded
 advertisement URLs to point to a user-specified local image,
 essentially performing a URI redirection on behalf of the content
 consumer (i.e., the end user).  Such URI manipulations are outside of
 the OPES framework scope, but cannot be effectively eliminated from
 the real world.

8. Consideration (4.2) 'Reference validity'

 "All proposed services must define their impact on inter- and intra-
 document reference validity" [RFC3238].
 The OPES framework does not propose adaptation services.  However,
 OPES tracing requirements include identification of OPES
 intermediaries and services (for details, see "Notification"
 consideration sections in this document).  It is required that

Babir & Rousskov Informational [Page 11] RFC 3914 OPES Treatment of IAB Considerations October 2004

 provided identification can be used to locate information about the
 OPES intermediaries, including the description of impact on reference
 validity [RFC3897].

9. Consideration (4.3) 'Addressing extensions'

 "Any services that cannot be achieved while respecting the above two
 considerations may be reviewed as potential requirements for Internet
 application addressing architecture extensions, but must not be
 undertaken as ad hoc fixes" [RFC3238].
 OPES framework does not contain ad hoc fixes.  This document in
 combination with and other OPES documents should be sufficient to
 inform service creators of IAB considerations.  If a service does URI
 resolution or silently affects document reference validity, the
 authors are requested to review service impact on Internet
 application addressing architecture and work within IETF on potential
 extension requirements.  Such actions would be outside of the current
 OPES framework.

10. Consideration (5.1) 'Privacy'

 "The overall OPES framework must provide for mechanisms for end users
 to determine the privacy policies of OPES intermediaries" [RFC3238].
 OPES tracing mechanisms allow end users to identify OPES
 intermediaries (for details, see "Notification" consideration
 sections in this document).  It is required that provided
 identification can be used to locate information about the OPES
 intermediaries, including their privacy policies.
 The term "privacy policy" is not defined in this context (by IAB or
 OPES working group).  OPES tracing mechanisms allow end users and
 content providers to identify an OPES system and/or intermediaries.
 It is believed that once an OPES system is identified, it would be
 possible to locate relevant information about that system, including
 information relevant to requesters perception of privacy policy or
 reference validity.

11. Consideration 'Encryption'

 "If OPES is chartered, the OPES working group will also have to
 explicitly decide and document whether the OPES architecture must be
 compatible with the use of end-to-end encryption by one or more ends
 of an OPES-involved session.  If OPES was compatible with end-to-end
 encryption, this would effectively ensure that OPES boxes would be

Babir & Rousskov Informational [Page 12] RFC 3914 OPES Treatment of IAB Considerations October 2004

 restricted to ones that are known, trusted, explicitly addressed at
 the IP layer, and authorized (by the provision of decryption keys) by
 at least one of the ends" [RFC3238].
 The above quoted requirement was not explicitly listed as on of the
 IAB considerations, but still needs to be addressed.  The context of
 the quote implies that the phrase "end-to-end encryption" refers to
 encryption along all links of the end-to-end path, with the OPES
 intermediaries as encrypting/decrypting participants or hops (e.g.,
 encryption between the provider and the OPES intermediaries, and
 between the OPES intermediaries and the client).
 Since OPES processors are regular hops on the application protocol
 path, OPES architecture allows for such encryption, provided the
 application protocol being adapted supports it.  Hop-by-hop
 encryption would do little good for the overall application message
 path protection if callout services have to receive unencrypted
 content.  To allow for complete link encryption coverage, OPES
 callout protocol (OCP) supports encryption of OCP connections between
 an OPES processor and a callout server via optional (negotiated)
 transport encryption mechanisms [I-D.ietf-opes-ocp-core].
 For example, TLS encryption [RFC2817] can be used among HTTP hops
 (some of which could be OPES processors) and between each OPES
 processor and a callout server.

12. Security Considerations

 This document does not define any mechanisms that may be subject to
 security considerations.  This document scope is to address specific
 IAB considerations.  Security of OPES mechanisms are discussed in
 Security Considerations sections of the corresponding OPES framework
 documents.
 For example, OPES tracing mechanisms assist content providers and
 consumers in protecting content integrity and confidentiality by
 requiring OPES intermediaries to disclose their presence.  Security
 of the tracing mechanism is discussed in the Security Considerations
 section of [RFC3897].

13. Compliance

 This document may be perceived as a proof of OPES compliance with IAB
 implied recommendations.  However, this document does not introduce
 any compliance subjects.  Compliance of OPES implementations is
 defined in other OPES documents discussed above.

Babir & Rousskov Informational [Page 13] RFC 3914 OPES Treatment of IAB Considerations October 2004

14. References

14.1. Normative References

 [RFC3238]                     Floyd, S. and L. Daigle, "IAB
                               Architectural and Policy Considerations
                               for Open Pluggable Edge Services", RFC
                               3238, January 2002.
 [RFC3752]                     Barbir, A., Burger, E., Chen, R.,
                               McHenry, S., Orman, H. and R. Penno,
                               "Open Pluggable Edge Services (OPES)
                               Use Cases and Deployment Scenarios",
                               RFC 3752, April 2004.
 [RFC3835]                     Barbir, A., Penno, R., Chen, R.,
                               Hofmann, M., and H. Orman, "An
                               Architecture for Open Pluggable Edge
                               Services (OPES)", RFC 3835, August
                               2004.
 [RFC3897]                     Barbir, A., "Open Pluggable Edge
                               Services (OPES) Entities and End Points
                               Communication", RFC 3897, September
                               2004.

14.2. Informative References

 [RFC2227]                     Mogul, J. and P. Leach, "Simple
                               Hit-Metering and Usage-Limiting for
                               HTTP", RFC 2227, October 1997.
 [RFC2616]                     Fielding, R., Gettys, J., Mogul, J.,
                               Frystyk, H., Masinter, L., Leach, P.
                               and T. Berners-Lee, "Hypertext Transfer
                               Protocol -- HTTP/1.1", RFC 2616, June
                               1999.
 [RFC2817]                     Khare, R. and S. Lawrence, "Upgrading
                               to TLS Within HTTP/1.1", RFC 2817, May
                               2000.
 [I-D.ietf-opes-http]          Rousskov, A. and M. Stecher, "HTTP
                               adaptation with OPES", Work in
                               Progress, October 2003.

Babir & Rousskov Informational [Page 14] RFC 3914 OPES Treatment of IAB Considerations October 2004

 [I-D.ietf-opes-ocp-core]      Rousskov, A., "OPES Callout Protocol
                               Core", Work in Progress, November 2003.

Authors' Addresses

 Abbie Barbir
 Nortel Networks
 3500 Carling Avenue
 Nepean, Ontario
 CA
 Phone: +1 613 763 5229
 EMail: abbieb@nortelnetworks.com
 Alex Rousskov
 The Measurement Factory
 EMail: rousskov@measurement-factory.com
 URI:   http://www.measurement-factory.com/

Babir & Rousskov Informational [Page 15] RFC 3914 OPES Treatment of IAB Considerations October 2004

Full Copyright Statement

 Copyright (C) The Internet Society (2004).
 This document is subject to the rights, licenses and restrictions
 contained in BCP 78, and except as set forth therein, the authors
 retain all their rights.
 This document and the information contained herein are provided on an
 "AS IS" basis and THE CONTRIBUTOR, THE ORGANIZATION HE/S HE
 REPRESENTS OR IS SPONSORED BY (IF ANY), THE INTERNET SOCIETY AND THE
 INTERNET ENGINEERING TASK FORCE DISCLAIM ALL WARRANTIES, EXPRESS OR
 IMPLIED, INCLUDING BUT NOT LIMITED TO ANY WARRANTY THAT THE USE OF
 THE INFORMATION HEREIN WILL NOT INFRINGE ANY RIGHTS OR ANY IMPLIED
 WARRANTIES OF MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE.

Intellectual Property

 The IETF takes no position regarding the validity or scope of any
 Intellectual Property Rights or other rights that might be claimed to
 pertain to the implementation or use of the technology described in
 this document or the extent to which any license under such rights
 might or might not be available; nor does it represent that it has
 made any independent effort to identify any such rights.  Information
 on the IETF's procedures with respect to rights in IETF Documents can
 be found in BCP 78 and BCP 79.
 Copies of IPR disclosures made to the IETF Secretariat and any
 assurances of licenses to be made available, or the result of an
 attempt made to obtain a general license or permission for the use of
 such proprietary rights by implementers or users of this
 specification can be obtained from the IETF on-line IPR repository at
 http://www.ietf.org/ipr.
 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.

Acknowledgement

 Funding for the RFC Editor function is currently provided by the
 Internet Society.

Babir & Rousskov Informational [Page 16]

/data/webs/external/dokuwiki/data/pages/rfc/rfc3914.txt · Last modified: 2004/10/04 18:28 by 127.0.0.1

Donate Powered by PHP Valid HTML5 Valid CSS Driven by DokuWiki