CDNI Logging Interface
draft-ietf-cdni-logging-22

When TLS is used, the general TLS usage guidance in [RFC7525] MUST be
   followed.

   The SHA256-hash directive inside the CDNI Logging File provides
   additional integrity protection, this time targeting potential
   corruption of the CDNI logging information during the CDNI Logging
   File generation, storage or exchange.  This mechanism does not itself
   allow restoration of the corrupted CDNI Logging information, but it
   allows detection of such corruption and therefore triggering of
   appropriate corrective actions (e.g., discard of corrupted
   information, attempt to re-obtain the CDNI Logging information).
   Note that the SHA256-hash does not protect against tampering by a
   third party, since such a third party could have recomputed and
   updated the SHA256-hash after tampering.  Protection against third
   party tampering can be achieved as discussed above through the use of
   TLS.

7.2.  Denial of Service

   This document does not define specific mechanism to protect against
   Denial of Service (DoS) attacks on the Logging Interface.  However,
   the CDNI Logging feed and CDNI Logging pull endpoints are typically
   to be accessed only by a very small number of valid remote endpoints
   and therefore can be easily protected against DoS attacks through the
   usual conventional DOS protection mechanisms such as firewalling or
   use of Virtual Private Networks (VPNs).

   Protection of dCDN Surrogates against spoofed delivery requests is
   outside the scope of the CDNI Logging interface.

7.3.  Privacy

   CDNs have the opportunity to collect detailed information about the
   downloads performed by End Users.  A dCDN is expected to collect such
   information into CDNI Logging Files, which are then communicated to
   an uCDN.

   Having detailed CDNI logging information known by the dCDN in itself
   does not represent a particular privacy concern since the dCDN is
   obviously fully aware of all information logged since it generated
   the information in the first place.  Making detailed CDNI logging
   information known to the uCDN does not represent a particular privacy
   concern because the uCDN is already exposed at request redirection
   time to most of the information that shows up as CDNI logging
   information (e.g., enduser IP@, URL, HTTP headers - at least when
   HTTP redirection is used between uCDN and dCDN).  Transporting
   detailed CDNI logging information over the HTTP based CDNI Logging

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   Interface does not represent a particular privacy concern because it
   is protected by usual IETF privacy-protection mechanism (e.g.,TLS).

   However, one privacy concern arises from the fact that large volumes
   of detailed information about content delivery to users, potentially
   traceable back to indvidual users, may be collected in CDNI Logging
   files.  These CDNI Logging files represent high-value targets, likely
   concentrated in a fairly centralised system (although the CDNI
   Logging architecture does not mandate a particular level of
   centralisation/distribution) and at risk of potential data
   exfiltration.  Note that the means of such data exfiltration are
   beyond the scope of the CDNI Logging interface itself (e.g.,
   corrupted employee, corrupted logging storage system,...).  This
   privacy concern calls for some protection.

   The collection of large volumes of such information into CDNI Logging
   Files introduces potential End Users privacy protection concerns.
   Mechanisms to address these concerns are discussed in the definition
   of the c-groupid field specified in Section 3.4.1.

   The use of mutually authenticated TLS to establish a secure session
   for the transport of the CDNI Logging feed and CDNI Logging pull as
   discussed in Section 7.1 provides confidentiality while the logging
   information is in transit and prevents any party other than the
   authorised uCDN to gain access to the logging information.

   We also note that the query string portion of the URL that may be
   conveyed inside the cs-uri and u-uri fields of CDNI Logging Files, or
   the HTTP cookies( [RFC6265]) that may be conveyed as part of the
   cs(<HTTP-header-name>) field of CDNI Logging files, may contain
   personnal information or information that can be exploited to derive
   personal information.  Where this is a concern, the CDNI Logging
   interface specification allows the dCDN to not include the cs-uri and
   to include a u-uri that removes (or hides) the sensitive part of the
   query string and allows the dCDN to not include the cs(<HTTP-header-
   name>) fields corresponding to HTTP headers associated with cookies.

8.  Acknowledgments

   This document borrows from the W3C Extended Log Format [ELF].

   Rob Murray significantly contributed into the text of Section 4.1.

   The authors thank Ben Niven-Jenkins, Kevin Ma, David Mandelberg and
   Ray van Brandenburg for their ongoing input.

   Brian Trammel and Rich Salz made significant contributions into
   making this interface privacy-friendly.

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   Finally, we also thank Sebastien Cubaud, Pawel Grochocki, Christian
   Jacquenet, Yannick Le Louedec, Anne Marrec, Emile Stephan, Fabio
   Costa, Sara Oueslati, Yvan Massot, Renaud Edel, Joel Favier and the
   contributors of the EU FP7 OCEAN project for their input in the early
   versions of this document.

9.  References

9.1.  Normative References

   [RFC2119]  Bradner, S., "Key words for use in RFCs to Indicate
              Requirement Levels", BCP 14, RFC 2119,
              DOI 10.17487/RFC2119, March 1997,
              <http://www.rfc-editor.org/info/rfc2119>.

   [RFC3339]  Klyne, G. and C. Newman, "Date and Time on the Internet:
              Timestamps", RFC 3339, DOI 10.17487/RFC3339, July 2002,
              <http://www.rfc-editor.org/info/rfc3339>.

   [RFC3986]  Berners-Lee, T., Fielding, R., and L. Masinter, "Uniform
              Resource Identifier (URI): Generic Syntax", STD 66,
              RFC 3986, DOI 10.17487/RFC3986, January 2005,
              <http://www.rfc-editor.org/info/rfc3986>.

   [RFC4122]  Leach, P., Mealling, M., and R. Salz, "A Universally
              Unique IDentifier (UUID) URN Namespace", RFC 4122,
              DOI 10.17487/RFC4122, July 2005,
              <http://www.rfc-editor.org/info/rfc4122>.

   [RFC4287]  Nottingham, M., Ed. and R. Sayre, Ed., "The Atom
              Syndication Format", RFC 4287, DOI 10.17487/RFC4287,
              December 2005, <http://www.rfc-editor.org/info/rfc4287>.

   [RFC5005]  Nottingham, M., "Feed Paging and Archiving", RFC 5005,
              DOI 10.17487/RFC5005, September 2007,
              <http://www.rfc-editor.org/info/rfc5005>.

   [RFC5226]  Narten, T. and H. Alvestrand, "Guidelines for Writing an
              IANA Considerations Section in RFCs", BCP 26, RFC 5226,
              DOI 10.17487/RFC5226, May 2008,
              <http://www.rfc-editor.org/info/rfc5226>.

   [RFC5234]  Crocker, D., Ed. and P. Overell, "Augmented BNF for Syntax
              Specifications: ABNF", STD 68, RFC 5234,
              DOI 10.17487/RFC5234, January 2008,
              <http://www.rfc-editor.org/info/rfc5234>.

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   [RFC7230]  Fielding, R., Ed. and J. Reschke, Ed., "Hypertext Transfer
              Protocol (HTTP/1.1): Message Syntax and Routing",
              RFC 7230, DOI 10.17487/RFC7230, June 2014,
              <http://www.rfc-editor.org/info/rfc7230>.

   [RFC7231]  Fielding, R., Ed. and J. Reschke, Ed., "Hypertext Transfer
              Protocol (HTTP/1.1): Semantics and Content", RFC 7231,
              DOI 10.17487/RFC7231, June 2014,
              <http://www.rfc-editor.org/info/rfc7231>.

   [RFC7232]  Fielding, R., Ed. and J. Reschke, Ed., "Hypertext Transfer
              Protocol (HTTP/1.1): Conditional Requests", RFC 7232,
              DOI 10.17487/RFC7232, June 2014,
              <http://www.rfc-editor.org/info/rfc7232>.

   [RFC7233]  Fielding, R., Ed., Lafon, Y., Ed., and J. Reschke, Ed.,
              "Hypertext Transfer Protocol (HTTP/1.1): Range Requests",
              RFC 7233, DOI 10.17487/RFC7233, June 2014,
              <http://www.rfc-editor.org/info/rfc7233>.

   [RFC7234]  Fielding, R., Ed., Nottingham, M., Ed., and J. Reschke,
              Ed., "Hypertext Transfer Protocol (HTTP/1.1): Caching",
              RFC 7234, DOI 10.17487/RFC7234, June 2014,
              <http://www.rfc-editor.org/info/rfc7234>.

   [RFC7235]  Fielding, R., Ed. and J. Reschke, Ed., "Hypertext Transfer
              Protocol (HTTP/1.1): Authentication", RFC 7235,
              DOI 10.17487/RFC7235, June 2014,
              <http://www.rfc-editor.org/info/rfc7235>.

   [RFC7525]  Sheffer, Y., Holz, R., and P. Saint-Andre,
              "Recommendations for Secure Use of Transport Layer
              Security (TLS) and Datagram Transport Layer Security
              (DTLS)", BCP 195, RFC 7525, DOI 10.17487/RFC7525, May
              2015, <http://www.rfc-editor.org/info/rfc7525>.

   [RFC7540]  Belshe, M., Peon, R., and M. Thomson, Ed., "Hypertext
              Transfer Protocol Version 2 (HTTP/2)", RFC 7540,
              DOI 10.17487/RFC7540, May 2015,
              <http://www.rfc-editor.org/info/rfc7540>.

9.2.  Informative References

   [CHAR_SET]
              "IANA Character Sets registry",
              <http://www.iana.org/assignments/character-sets/
              character-sets.xml>.

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   [ELF]      Phillip M. Hallam-Baker, and Brian Behlendorf, "Extended
              Log File Format, W3C (work in progress), WD-logfile-
              960323", <http://www.w3.org/TR/WD-logfile.html>.

   [I-D.ietf-cdni-metadata]
              Niven-Jenkins, B., Murray, R., Caulfield, M., and K. Ma,
              "CDN Interconnection Metadata", draft-ietf-cdni-
              metadata-12 (work in progress), October 2015.

   [I-D.ietf-tls-rfc5246-bis]
              Dierks, T. and E. Rescorla, "The Transport Layer Security
              (TLS) Protocol Version 1.3", draft-ietf-tls-rfc5246-bis-00
              (work in progress), April 2014.

   [I-D.snell-atompub-link-extensions]
              Snell, J., "Atom Link Extensions", draft-snell-atompub-
              link-extensions-09 (work in progress), June 2012.

   [RFC1945]  Berners-Lee, T., Fielding, R., and H. Frystyk, "Hypertext
              Transfer Protocol -- HTTP/1.0", RFC 1945,
              DOI 10.17487/RFC1945, May 1996,
              <http://www.rfc-editor.org/info/rfc1945>.

   [RFC2818]  Rescorla, E., "HTTP Over TLS", RFC 2818,
              DOI 10.17487/RFC2818, May 2000,
              <http://www.rfc-editor.org/info/rfc2818>.

   [RFC5869]  Krawczyk, H. and P. Eronen, "HMAC-based Extract-and-Expand
              Key Derivation Function (HKDF)", RFC 5869,
              DOI 10.17487/RFC5869, May 2010,
              <http://www.rfc-editor.org/info/rfc5869>.

   [RFC6234]  Eastlake 3rd, D. and T. Hansen, "US Secure Hash Algorithms
              (SHA and SHA-based HMAC and HKDF)", RFC 6234,
              DOI 10.17487/RFC6234, May 2011,
              <http://www.rfc-editor.org/info/rfc6234>.

   [RFC6265]  Barth, A., "HTTP State Management Mechanism", RFC 6265,
              DOI 10.17487/RFC6265, April 2011,
              <http://www.rfc-editor.org/info/rfc6265>.

   [RFC6707]  Niven-Jenkins, B., Le Faucheur, F., and N. Bitar, "Content
              Distribution Network Interconnection (CDNI) Problem
              Statement", RFC 6707, DOI 10.17487/RFC6707, September
              2012, <http://www.rfc-editor.org/info/rfc6707>.

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   [RFC6770]  Bertrand, G., Ed., Stephan, E., Burbridge, T., Eardley,
              P., Ma, K., and G. Watson, "Use Cases for Content Delivery
              Network Interconnection", RFC 6770, DOI 10.17487/RFC6770,
              November 2012, <http://www.rfc-editor.org/info/rfc6770>.

   [RFC6983]  van Brandenburg, R., van Deventer, O., Le Faucheur, F.,
              and K. Leung, "Models for HTTP-Adaptive-Streaming-Aware
              Content Distribution Network Interconnection (CDNI)",
              RFC 6983, DOI 10.17487/RFC6983, July 2013,
              <http://www.rfc-editor.org/info/rfc6983>.

   [RFC7336]  Peterson, L., Davie, B., and R. van Brandenburg, Ed.,
              "Framework for Content Distribution Network
              Interconnection (CDNI)", RFC 7336, DOI 10.17487/RFC7336,
              August 2014, <http://www.rfc-editor.org/info/rfc7336>.

   [RFC7337]  Leung, K., Ed. and Y. Lee, Ed., "Content Distribution
              Network Interconnection (CDNI) Requirements", RFC 7337,
              DOI 10.17487/RFC7337, August 2014,
              <http://www.rfc-editor.org/info/rfc7337>.

   [RFC7736]  Ma, K., "Content Delivery Network Interconnection (CDNI)
              Media Type Registration", RFC 7736, DOI 10.17487/RFC7736,
              December 2015, <http://www.rfc-editor.org/info/rfc7736>.

Authors' Addresses

   Francois Le Faucheur (editor)
   Cisco Systems
   E.Space Park - Batiment D
   6254 Allee des Ormes - BP 1200
   Mougins cedex  06254
   FR

   Phone: +33 4 97 23 26 19
   Email: flefauch@cisco.com

   Gilles Bertrand (editor)
   Orange
   38-40 rue du General Leclerc
   Issy les Moulineaux  92130
   FR

   Phone: +33 1 45 29 89 46
   Email: gilles.bertrand@orange.com

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   Iuniana Oprescu (editor)
   Orange
   38-40 rue du General Leclerc
   Issy les Moulineaux  92130
   FR

   Phone: +33 6 89 06 92 72
   Email: iuniana.oprescu@orange.com

   Roy Peterkofsky
   Skytide, Inc.
   One Kaiser Plaza, Suite 785
   Oakland  CA 94612
   USA

   Phone: +01 510 250 4284
   Email: roy@skytide.com

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