IP Flow Anonymization Support
RFC 6235

• Status
• IESG evaluation record
• IESG writeups
• Email expansions
• History

• Versions
• 06

Internet Engineering Task Force (IETF)                         E. Boschi
Request for Comments: 6235                                   B. Trammell
Category: Experimental                                        ETH Zurich
ISSN: 2070-1721                                                 May 2011

                     IP Flow Anonymization Support

Abstract

   This document describes anonymization techniques for IP flow data and
   the export of anonymized data using the IP Flow Information Export
   (IPFIX) protocol.  It categorizes common anonymization schemes and
   defines the parameters needed to describe them.  It provides
   guidelines for the implementation of anonymized data export and
   storage over IPFIX, and describes an information model and Options-
   based method for anonymization metadata export within the IPFIX
   protocol or storage in IPFIX Files.

Status of This Memo

   This document is not an Internet Standards Track specification; it is
   published for examination, experimental implementation, and
   evaluation.

   This document defines an Experimental Protocol for the Internet
   community.  This document is a product of the Internet Engineering
   Task Force (IETF).  It represents the consensus of the IETF
   community.  It has received public review and has been approved for
   publication by the Internet Engineering Steering Group (IESG).  Not
   all documents approved by the IESG are a candidate for any level of
   Internet Standard; see Section 2 of RFC 5741.

   Information about the current status of this document, any errata,
   and how to provide feedback on it may be obtained at
   http://www.rfc-editor.org/info/rfc6235.

Boschi & Trammell             Experimental                      [Page 1]
RFC 6235              IP Flow Anonymization Support             May 2011

Copyright Notice

   Copyright (c) 2011 IETF Trust and the persons identified as the
   document authors.  All rights reserved.

   This document is subject to BCP 78 and the IETF Trust's Legal
   Provisions Relating to IETF Documents
   (http://trustee.ietf.org/license-info) in effect on the date of
   publication of this document.  Please review these documents
   carefully, as they describe your rights and restrictions with respect
   to this document.  Code Components extracted from this document must
   include Simplified BSD License text as described in Section 4.e of
   the Trust Legal Provisions and are provided without warranty as
   described in the Simplified BSD License.

Table of Contents

   1. Introduction ....................................................4
      1.1. IPFIX Protocol Overview ....................................4
      1.2. IPFIX Documents Overview ...................................5
      1.3. Anonymization within the IPFIX Architecture ................5
      1.4. Supporting Experimentation with Anonymization ..............6
   2. Terminology .....................................................6
   3. Categorization of Anonymization Techniques ......................7
   4. Anonymization of IP Flow Data ...................................8
      4.1. IP Address Anonymization ..................................10
           4.1.1. Truncation .........................................11
           4.1.2. Reverse Truncation .................................11
           4.1.3. Permutation ........................................11
           4.1.4. Prefix-Preserving Pseudonymization .................12
      4.2. MAC Address Anonymization .................................12
           4.2.1. Truncation .........................................13
           4.2.2. Reverse Truncation .................................13
           4.2.3. Permutation ........................................14
           4.2.4. Structured Pseudonymization ........................14
      4.3. Timestamp Anonymization ...................................15
           4.3.1. Precision Degradation ..............................15
           4.3.2. Enumeration ........................................16
           4.3.3. Random Shifts ......................................16
      4.4. Counter Anonymization .....................................16
           4.4.1. Precision Degradation ..............................17
           4.4.2. Binning ............................................17
           4.4.3. Random Noise Addition ..............................17
      4.5. Anonymization of Other Flow Fields ........................18
           4.5.1. Binning ............................................18
           4.5.2. Permutation ........................................18
   5. Parameters for the Description of Anonymization Techniques .....19
      5.1. Stability .................................................19

Boschi & Trammell             Experimental                      [Page 2]
RFC 6235              IP Flow Anonymization Support             May 2011

      5.2. Truncation Length .........................................19