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diff --git a/doc/rfc/rfc2804.txt b/doc/rfc/rfc2804.txt new file mode 100644 index 0000000..c198925 --- /dev/null +++ b/doc/rfc/rfc2804.txt @@ -0,0 +1,563 @@ + + + + + + +Network Working Group IAB +Request for Comments: 2804 IESG +Category: Informational May 2000 + + + IETF Policy on Wiretapping + +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 (2000). All Rights Reserved. + +Abstract + + The Internet Engineering Task Force (IETF) has been asked to take a + position on the inclusion into IETF standards-track documents of + functionality designed to facilitate wiretapping. + + This memo explains what the IETF thinks the question means, why its + answer is "no", and what that answer means. + +1. Summary position + + The IETF has decided not to consider requirements for wiretapping as + part of the process for creating and maintaining IETF standards. + + It takes this position for the following basic reasons: + + - The IETF, an international standards body, believes itself to be + the wrong forum for designing protocol or equipment features that + address needs arising from the laws of individual countries, + because these laws vary widely across the areas that IETF standards + are deployed in. Bodies whose scope of authority correspond to a + single regime of jurisdiction are more appropriate for this task. + + - The IETF sets standards for communications that pass across + networks that may be owned, operated and maintained by people from + numerous jurisdictions with numerous requirements for privacy. In + light of these potentially divergent requirements, the IETF + believes that the operation of the Internet and the needs of its + users are best served by making sure the security properties of + + + + + +IAB & IESG Informational [Page 1] + +RFC 2804 IETF Policy on Wiretapping May 2000 + + + connections across the Internet are as well known as possible. At + the present stage of our ignorance this means making them as free + from security loopholes as possible. + + - The IETF believes that in the case of traffic that is today going + across the Internet without being protected by the end systems (by + encryption or other means), the use of existing network features, + if deployed intelligently, provides extensive opportunities for + wiretapping, and should be sufficient under presently seen + requirements for many cases. The IETF does not see an engineering + solution that allows such wiretapping when the end systems take + adequate measures to protect their communications. + + - The IETF believes that adding a requirement for wiretapping will + make affected protocol designs considerably more complex. + Experience has shown that complexity almost inevitably jeopardizes + the security of communications even when it is not being tapped by + any legal means; there are also obvious risks raised by having to + protect the access to the wiretap. This is in conflict with the + goal of freedom from security loopholes. + + - The IETF restates its strongly held belief, stated at greater + length in [RFC 1984], that both commercial development of the + Internet and adequate privacy for its users against illegal + intrusion requires the wide availability of strong cryptographic + technology. + + - On the other hand, the IETF believes that mechanisms designed to + facilitate or enable wiretapping, or methods of using other + facilities for such purposes, should be openly described, so as to + ensure the maximum review of the mechanisms and ensure that they + adhere as closely as possible to their design constraints. The IETF + believes that the publication of such mechanisms, and the + publication of known weaknesses in such mechanisms, is a Good + Thing. + +2. The Raven process + + The issue of the IETF doing work on legal intercept technologies came + up as a byproduct of the extensive work that the IETF is now doing in + the area if IP-based telephony. + + In the telephony world, there has been a tradition of cooperation + (often mandated by law) between law enforcement agencies and + telephone equipment operators on wiretapping, leading to companies + that build telephone equipment adding wiretapping features to their + telephony-related equipment, and an emerging consensus in the + + + + +IAB & IESG Informational [Page 2] + +RFC 2804 IETF Policy on Wiretapping May 2000 + + + industry of how to build and manage such features. Some traditional + telephony standards organizations have supported this by adding + intercept features to their telephony-related standards. + + Since the future of the telephone seems to be intertwined with the + Internet it is inevitable that the primary Internet standards + organization would be faced with the issue sooner or later. + + In this case, some of the participants of one of the IETF working + groups working on a new standard for communication between components + of a distributed phone switch brought up the issue. Since adding + features of this type would be something the IETF had never done + before, the IETF management decided to have a public discussion + before deciding if the working group should go ahead. A new mailing + list was created (the Raven mailing list, see + http://www.ietf.org/mailman/listinfo/raven) for this discussion. + Close to 500 people subscribed to the list and about 10% of those + sent at least one message to the list. The discussion on this list + was a precursor to a discussion held during the IETF plenary in + Washington, D.C. + + Twenty-nine people spoke during the plenary session. Opinions ranged + from libertarian: 'governments have no right to wiretap' - to + pragmatic: 'it will be done somewhere, best have it done where the + technology was developed'. At the end of the discussion there was a + show of hands to indicate opinions: should the IETF add special + features, not do this or abstain. Very few people spoke out strongly + in support for adding the intercept features, while many spoke out + against it, but a sizable portion of the audience refused to state an + opinion (raised their hands when asked for "abstain" in the show of + hands). + + This is the background on the basis of which the Internet Engineering + Steering Group (IESG) and the Internet Architecture Board (IAB) was + asked to formulate a policy. + +3. A definition of wiretapping + + The various legal statutes defining wiretapping do not give adequate + definitions to distinguish between wiretapping and various other + activities at the technical level. For the purposes of this memo, the + following definition of wiretapping is used: + + Wiretapping is what occurs when information passed across the + Internet from one party to one or more other parties is delivered to + a third party: + + + + + +IAB & IESG Informational [Page 3] + +RFC 2804 IETF Policy on Wiretapping May 2000 + + + 1. Without the sending party knowing about the third party + + 2. Without any of the recipient parties knowing about the delivery to + the third party + + 3. When the normal expectation of the sender is that the transmitted + information will only be seen by the recipient parties or parties + obliged to keep the information in confidence + + 4. When the third party acts deliberately to target the transmission + of the first party, either because he is of interest, or because + the second party's reception is of interest. + + The term "party", as used here, can refer to one person, a group of + persons, or equipment acting on behalf of persons; the term "party" + is used for brevity. + + Of course, many wiretaps will be bidirectional, monitoring traffic + sent by two or more parties to each other. + + Thus, for instance, monitoring public newsgroups is not wiretapping + (condition 3 violated), random monitoring of a large population is + not wiretapping (condition 4 violated), a recipient passing on + private email is not wiretapping (condition 2 violated). + + An Internet equivalent of call tracing by means of accounting logs + (sometimes called "pen registers") that is a feature of the telephone + network is also wiretapping by this definition, since the normal + expectation of the sender is that the company doing the accounting + will keep this information in confidence. + + Wiretapping may logically be thought of as 3 distinct steps: + + - Capture - getting information off the wire that contains the + information wanted. + + - Filtering - selecting the information wanted from information + gathered by accident. + + - Delivery - transmitting the information wanted to the ones who want + it. + + The term applies to the whole process; for instance, random + monitoring followed by filtering to extract information about a + smaller group of parties would be wiretapping by this definition. + + In all these stages, the possibility of using or abusing mechanisms + defined for this purpose for other purposes exists. + + + +IAB & IESG Informational [Page 4] + +RFC 2804 IETF Policy on Wiretapping May 2000 + + + This definition deliberately does not include considerations of: + + - Whether the wiretap is legal or not, since that is a legal, not a + technical matter. + + - Whether the wiretap occurs in real time, or can be performed after + the fact by looking at information recorded for other purposes + (such as the accounting example given above). + + - What the medium targeted by the wiretap is - whether it is email, + IP telephony, Web browsing or EDI transfers. + + These questions are believed to be irrelevant to the policy outlined + in this memo. + + Wiretapping is also sometimes called "interception", but that term is + also used in a sense that is considerably wider than the monitoring + of data crossing networks, and is therefore not used here. + +4. Why the IETF does not take a moral position + + Much of the debate about wiretapping has centered around the question + of whether wiretapping is morally evil, no matter who does it, + necessary in any civilized society, or an effective tool for catching + criminals that has been abused in the past and will be abused again. + + The IETF has decided not to take a position in this matter, since: + + - There is no clear consensus around a single position in the IETF. + + - There is no means of detecting the morality of an act "on the + wire". Since the IETF deals with protocol standardization, not + protocol deployment, it is not in a position to dictate that its + product is only used in moral or legal ways. + + However, a few observations can be made: + + - Experience shows that tools which are effective for a purpose tend + to be used for that purpose. + + - Experience shows that tools designed for one purpose that are + effective for another tend to be used for that other purpose too, + no matter what its designers intended. + + - Experience shows that if a vulnerability exists in a security + system, it is likely that someone will take advantage of it sooner + or later. + + + + +IAB & IESG Informational [Page 5] + +RFC 2804 IETF Policy on Wiretapping May 2000 + + + - Experience shows that human factors, not technology per se, is the + biggest single source of such vulnerabilities. + + What this boils down to is that if effective tools for wiretapping + exist, it is likely that they will be used as designed, for purposes + legal in their jurisdiction, and also in ways they were not intended + for, in ways that are not legal in that jurisdiction. When weighing + the development or deployment of such tools, this should be borne in + mind. + +5. Utility considerations + + When designing any communications function, it is a relevant question + to ask if such functions efficiently perform the task they are + designed for, or whether the work spent in developing them is not, in + fact, worth the benefit gained. + + Given that there are no specific proposals being developed in the + IETF, the IETF cannot weigh proposals for wiretapping directly in + this manner. + + However, as above, a few general observations can be made: + + - Wiretapping by copying the bytes passed between two users of the + Internet with known, static points of attachment is not hard. + Standard functions designed for diagnostic purposes can accomplish + this. + + - Correlating users' identities with their points of attachment to + the Internet can be significantly harder, but not impossible, if + the user uses standard means of identification. However, this means + linking into multiple Internet subsystems used for address + assignment, name resolution and so on; this is not trivial. + + - An adversary has several simple countermeasures available to defeat + wiretapping attempts, even without resorting to encryption. This + includes Internet cafes and anonymous dialups, anonymous remailers, + multi-hop login sessions and use of obscure communications media; + these are well known tools in the cracker community. + + - Of course, communications where the content is protected by strong + encryption can be easily recorded, but the content is still not + available to the wiretapper, defeating all information gathering + apart from traffic analysis. Since Internet data is already in + digital form, encrypting it is very simple for the end-user. + + + + + + +IAB & IESG Informational [Page 6] + +RFC 2804 IETF Policy on Wiretapping May 2000 + + + These things taken together mean that while wiretapping is an + efficient tool for use in situations where the target of a wiretap is + either ignorant or believes himself innocent of wrongdoing, + Internet-based wiretapping is a less useful tool than might be + imagined against an alerted and technically competent adversary. + +6. Security Considerations + + Wiretapping, by definition (see above), releases information that the + information sender did not expect to be released. + + This means that a system that allows wiretapping has to contain a + function that can be exercised without alerting the information + sender to the fact that his desires for privacy are not being met. + + This, in turn, means that one has to design the system in such a way + that it cannot guarantee any level of privacy; at the maximum, it can + only guarantee it as long as the function for wiretapping is not + exercised. + + For instance, encrypted telephone conferences have to be designed in + such a way that the participants cannot know to whom any shared + keying material is being revealed. + + This means: + + - The system is less secure than it could be had this function not + been present. + + - The system is more complex than it could be had this function not + been present. + + - Being more complex, the risk of unintended security flaws in the + system is larger. + + Wiretapping, even when it is not being exercised, therefore lowers + the security of the system. + + + + + + + + + + + + + + +IAB & IESG Informational [Page 7] + +RFC 2804 IETF Policy on Wiretapping May 2000 + + +7. Acknowledgements + + This memo is endorsed by the IAB and the IESG. + + Their membership is: + + IAB: + + Harald Alvestrand + Randall Atkinson + Rob Austein + Brian Carpenter + Steve Bellovin + Jon Crowcroft + Steve Deering + Ned Freed + Tony Hain + Tim Howes + Geoff Huston + John Klensin + + + IESG: + + Fred Baker + Keith Moore + Patrik Falstrom + Erik Nordmark + Thomas Narten + Randy Bush + Bert Wijnen + Rob Coltun + Dave Oran + Jeff Schiller + Marcus Leech + Scott Bradner + Vern Paxson + April Marine + + The number of contributors to the discussion are too numerous to + list. + + + + + + + + + + +IAB & IESG Informational [Page 8] + +RFC 2804 IETF Policy on Wiretapping May 2000 + + +8. Author's Address + + This memo is authored by the IAB and the IESG. + + The chairs are: + + Fred Baker, IETF Chair + 519 Lado Drive + Santa Barbara California 93111 + + Phone: +1-408-526-4257 + EMail: fred@cisco.com + + + Brian E. Carpenter, IAB Chair + IBM + c/o iCAIR + Suite 150 + 1890 Maple Avenue + Evanston IL 60201 + USA + + EMail: brian@icair.org + +9. References + + [RFC 1984] IAB and IESG, "IAB and IESG Statement on Cryptographic + Technology and the Internet", RFC 1984, August 1996. + + + + + + + + + + + + + + + + + + + + + + + +IAB & IESG Informational [Page 9] + +RFC 2804 IETF Policy on Wiretapping May 2000 + + +9. Full Copyright Statement + + Copyright (C) The Internet Society (2000). All Rights Reserved. + + This document and translations of it may be copied and furnished to + others, and derivative works that comment on or otherwise explain it + or assist in its implementation may be prepared, copied, published + and distributed, in whole or in part, without restriction of any + kind, provided that the above copyright notice and this paragraph are + included on all such copies and derivative works. However, this + document itself may not be modified in any way, such as by removing + the copyright notice or references to the Internet Society or other + Internet organizations, except as needed for the purpose of + developing Internet standards in which case the procedures for + copyrights defined in the Internet Standards process must be + followed, or as required to translate it into languages other than + English. + + The limited permissions granted above are perpetual and will not be + revoked by the Internet Society or its successors or assigns. + + This document and the information contained herein is provided on an + "AS IS" basis and THE INTERNET SOCIETY AND THE INTERNET ENGINEERING + TASK FORCE DISCLAIMS 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. + +Acknowledgement + + Funding for the RFC Editor function is currently provided by the + Internet Society. + + + + + + + + + + + + + + + + + + + +IAB & IESG Informational [Page 10] + |