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Folks, Rather than discussing specific details of the current doc, I though it might be helpful to offer some text. The text below is my take as what I think we should be saying. Steve ------- Recent
revelations [cites]
about widespread monitoring of Internet communications by a
number of national
intelligence agencies has caused great concern in the IETF
community. The IETF
security
community has always considered passive wiretapping be a
feasible attack
against the confidentiality of Internet traffic while in transit
(or while in
storage en route to an end user). We also presume that active
attacks are
feasible, especially off-path active attacks, e.g., DNS cache
poisoning [cite].
Even on-path, man-in-the-middle (MITM) attacks are viewed as
possible, by some
classes of adversaries. The IETF has
developed a
set of security protocols to counter passive and active
wiretapping attacks,
e.g., IPsec, TLS, SSH, S/MIME, SRTP. All of these protocols
offer
confidentiality, via encryption, as a way to defend against
passive wiretapping.
They also employ cryptographic message authentication codes
(MACs) or digital
signatures to provide data integrity and authentication. The
cryptographic
mechanisms employed by these protocols are effective against a
very broad range
of attacks and adversaries. The IETF has
not ignored
the potential for passive and active wiretapping. In some
respects,
widespread monitoring of Internet communication by nation states
ought not be a
surprise. They qualify as threats against Internet
communication, i.e.,
motivated, capable adversaries. These adversaries have extensive
technical
capabilities and are motivated to collect information in support
of (their)
national security missions. Nonetheless, the scale of the
monitoring that has
been disclosed is considerably greater than what most IETF
community members
anticipated. The IETF
community
perceives a qualitative difference between targeting and
monitoring individual
Internet communications vs. very widespread (pervasive)
monitoring of such
communication. As a result, the IETF community has reached
consensus [cite] to
address the pervasive monitoring of Internet communications by
revisiting our
security protocol standards with a goal of making it easier for
users and
service providers to offer better protection for Internet
communications. IETF security
standards
provide a number of mechanisms to protect the application layer
content of
Internet communications. However, most
of these standards do not emphasize confidentiality for protocol
metadata,
other than what accrues from encapsulating such data at higher
layers. Based on
the disclosures cited above, the IETF community also has decided
that more
emphasis should be placed on protecting such metadata. The IETF
community
recognizes that not all aspects of Internet communication security are within the
purview of the IETF.
Communication security may be offered at multiple layers within
the protocol
hierarchy; the IETF does not create standards for all of these
layers. For
example, the IEEE has created encryption standards for layer 2
(LANs and MANs).
Security for Internet communications also is affected by design
and
implementation choices within hosts and servers, and most of
these are outside
of the scope of IETF standards. The IETF
community recognizes
that not all forms of monitoring of Internet traffic constitute
the sort of
attack that have motivated this declaration. Many Internet
service providers
monitor traffic on their nets in support of traffic engineering
and network
management. Such monitoring does not require access to
application layer
content, but it does require access to some types of metadata.
Many application
service providers access application layer content as part of
providing their
services. This access is outside of the scope of this effort.
Within an
enterprise network, monitoring of traffic often is performed in
support of
security, e.g., intrusion detection systems, anti-virus and
anti-spam
filtering. This type of monitoring has a legitimate purpose and
is within the
purview of an enterprise, so it too is not considered an attack
to be addressed
by this IETF effort. |