Opportunistic Security: Some Protection Most of the Time
RFC 7435
| Document | Type |
RFC - Informational
(December 2014; No errata)
Was draft-dukhovni-opportunistic-security (individual in sec area)
|
|
|---|---|---|---|
| Last updated | 2015-10-14 | ||
| Stream | IETF | ||
| Formats | plain text html pdf htmlized bibtex | ||
| Reviews | |||
| Stream | WG state | Submitted to IESG for Publication | |
| Document shepherd | Paul Hoffman | ||
| Shepherd write-up | Show (last changed 2014-08-25) | ||
| IESG | IESG state | RFC 7435 (Informational) | |
| Consensus Boilerplate | Yes | ||
| Telechat date | |||
| Responsible AD | Stephen Farrell | ||
| Send notices to | saag@ietf.org | ||
| IANA | IANA review state | Version Changed - Review Needed | |
| IANA action state | No IANA Actions | ||
Internet Engineering Task Force (IETF) V. Dukhovni
Request for Comments: 7435 Two Sigma
Category: Informational December 2014
ISSN: 2070-1721
Opportunistic Security: Some Protection Most of the Time
Abstract
This document defines the concept "Opportunistic Security" in the
context of communications protocols. Protocol designs based on
Opportunistic Security use encryption even when authentication is not
available, and use authentication when possible, thereby removing
barriers to the widespread use of encryption on the Internet.
Status of This Memo
This document is not an Internet Standards Track specification; it is
published for informational purposes.
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/rfc7435.
Copyright Notice
Copyright (c) 2014 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.
Dukhovni Informational [Page 1]
RFC 7435 Opportunistic Security December 2014
Table of Contents
1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . 2
1.1. Background . . . . . . . . . . . . . . . . . . . . . . . 2
1.2. A New Perspective . . . . . . . . . . . . . . . . . . . . 3
2. Terminology . . . . . . . . . . . . . . . . . . . . . . . . . 5
3. Opportunistic Security Design Principles . . . . . . . . . . 5
4. Example: Opportunistic TLS in SMTP . . . . . . . . . . . . . 8
5. Operational Considerations . . . . . . . . . . . . . . . . . 8
6. Security Considerations . . . . . . . . . . . . . . . . . . . 9
7. References . . . . . . . . . . . . . . . . . . . . . . . . . 10
7.1. Normative References . . . . . . . . . . . . . . . . . . 10
7.2. Informative References . . . . . . . . . . . . . . . . . 10
Acknowledgements . . . . . . . . . . . . . . . . . . . . . . . . 11
Author's Address . . . . . . . . . . . . . . . . . . . . . . . . 11
1. Introduction
1.1. Background
Historically, Internet security protocols have emphasized
comprehensive "all or nothing" cryptographic protection against both
passive and active attacks. With each peer, such a protocol achieves
either full protection or else total failure to communicate (hard
fail). As a result, operators often disable these security protocols
when users have difficulty connecting, thereby degrading all
communications to cleartext transmission.
Protection against active attacks requires authentication. The
ability to authenticate any potential peer on the Internet requires
an authentication mechanism that encompasses all such peers. No IETF
standard for authentication scales as needed and has been deployed
widely enough to meet this requirement.
The Public Key Infrastructure (PKI) model employed by browsers to
authenticate web servers (often called the "Web PKI") imposes cost
and management burdens that have limited its use. With so many
Certification Authorities (CAs), not all of which everyone is willing
to trust, the communicating parties don't always agree on a mutually
trusted CA. Without a mutually trusted CA, authentication fails,
leading to communications failure in protocols that mandate
authentication. These issues are compounded by operational
difficulties. For example, a common problem is for site operators to
forget to perform timely renewal of expiring certificates. In Web
PKI interactive applications, security warnings are all too frequent,
and end users learn to actively ignore security problems, or site
administrators decide that the maintenance cost is not worth the
benefit so they provide a cleartext-only service to their users.
Dukhovni Informational [Page 2]
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