RE: Last Call: <draft-mm-wg-effect-encrypt-13.txt> (Effect of Pervasive Encryption on Operators) to Informational RFC

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Roni

> -----Original Message-----
> From: ietf [mailto:ietf-bounces@xxxxxxxx] On Behalf Of Paul Wouters
> Sent: יום א 12 נובמבר 2017 15:02
> To: Stephane Bortzmeyer
> Cc: ietf@xxxxxxxx
> Subject: Re: Last Call: <draft-mm-wg-effect-encrypt-13.txt> (Effect of
> Pervasive Encryption on Operators) to Informational RFC
> 
> 
> 
> I concur with most of Stephane’s comments. And I find the use of the term
> “pervasive encryption” very problematic. Pervasive means:
> 
> “(especially of an unwelcome influence or physical effect) spreading widely
> throughout an area or a group of people.”
> 
> More encryption is never unwelcome to the enduser.
[Roni Even] I will argue this statement.  My experience is that the user care about the encryption of his content. As for privacy - do you see users stop using social media? Do they install applications that ask  for access to you contact, photos, location or like most users they just approve them.
> 
> If this document listed these practises, along with valid methods for
> operators to switch to, i could be convinced the document is useful. But as
> Stephane pointed out, a lot of these problems are desired features. That the
> operator has less networking debugging tools is an unavoidable side effect,
> but should not be used as an argument against more encryption.
> 
> But in its current form, it seems this document would be prime candidate for
> operator misbehaviour justification “sanctioned” by the IETF.
> 
> Note that I _do_ believe in the authors’ good intention of just documenting
> the new problems operators face. But the IETF will have taken these issues
> into consideration already before it published the RFCs.
> 
> This documents feels (unintentionally) that we need to go back to be
> drawing board to reconsider these operator issues.
> 
> Paul
> 
> > On Nov 12, 2017, at 19:55, Stephane Bortzmeyer <bortzmeyer@xxxxxx>
> wrote:
> >
> > On Mon, Nov 06, 2017 at 06:06:50AM -0800, The IESG
> > <iesg-secretary@xxxxxxxx> wrote a message of 37 lines which said:
> >
> >> The IESG has received a request from an individual submitter to
> >> consider the following document: - 'Effect of Pervasive Encryption on
> >> Operators' <draft-mm-wg-effect-encrypt-13.txt> as Informational RFC
> >
> > I'm quite concerned by this document. Basically, it seems to me it
> > deviates a lot from a simple description of current practices, and
> > goes into promoting them. The overall effect seems to me very
> > dangerous. One can easily read this document as "encryption is a pain
> > for the operators, we should not promote it too agressively".
> >
> > My opinion is that its publication as it is would inflict real harm to
> > the efforts of IETF to promote privacy (which implies, among other
> > things, a lot of encryption).
> >
> > The document also completely ignores network neutrality, not to
> > mention the end-to-end principle.
> >
> > More precisely:
> >
> >> This document discusses practices currently used by network operators
> >> to manage, operate, and secure their networks
> >
> > Actually, it does not "discuss": it describes them, using only the
> > arguments of the operators that use these practices, rarely
> > questioning them.
> >
> >> the impact of pervasive encryption
> >
> > Note that we are far from "pervasive encryption". For instance, the
> > DNS traffic is almost entirely in clear (RFC 7858).
> >
> >> For example, the traffic patterns between server and browser are
> >> dependent on browser supplier and version
> >
> > That's a good example of why HTTP sessions must be encrypted: the
> > User-Agent: field is very revealing, among other infos sent by the
> > browser, as exemplified by the Panopticlick
> > <https://panopticlick.eff.org/>
> >
> >> Network operators use packet captures and protocol-dissecting
> >> analyzers when responding to customer problems,
> >
> > Not all network operators are so benevolent. I doubt that many 30 $ or
> > 25 € / month ISP use tcpdump when the customer has a problem :-)
> > Seriously, this sentence is very dangerous because of:
> >
> >> The ability to identify the problem application's traffic is
> >> important and deep packet inspection (DPI) is often used for this
> >> purpose
> >
> > This really looks like an attempt to "sell" DPI by explaining that it
> > may benefit the users. Actually, I would like to see my ISP going into
> > such efforts to help me but I doubt it will be the case.
> >
> > Note that no ISP document the practices it actually use against user
> > flows. This is sufficient proof that they are not done in the interest
> > of the users.
> >
> >> For example, by investigating packet loss (from TCP sequence and
> >> acknowledgement numbers), round-trip-time (from TCP timestamp
> options
> >> or application-layer transactions, e.g., DNS or HTTP response time),
> >> TCP receive-window size, packet corruption, inefficient
> >> fragmentation, or application-layer problems, the operator can narrow
> >> the problem
> >
> > Almost all of these investigations can be performed even if TLS or SSH
> > is used. Again, it really seems an effort to make DPI acceptable.
> >
> >> Because of this, application server operators using increased
> >> encryption should expect to be called upon more frequently to assist
> >> with debugging and troubleshooting
> >
> > Hard to read this as something else than a threat "do not use
> > encryption or your business will suffer".
> >
> >> A common, early trigger for DDoS mitigation includes observing
> >> uncharacteristic traffic volumes or sources; congestion; or
> >> degradation of a given network or service.  One approach to mitigate
> >> such an attack involves distinguishing attacker traffic from
> >> legitimate user traffic.
> >
> > Are there really dDoS attacks using encryption? Hard data welcome.
> >
> >> Mobile networks especially rely on content/application based
> >> prioritization of Over-the-Top (OTT) services
> >
> > This is a very important point: if encryption really prevents
> > prioritization of some services over the others, then it means we need
> > more encryption, not less. If encryption can help preserve network
> > neutrality, this is a good reason to use it even more.
> >
> >> Due to the characteristics of the mobile link, performance-enhancing
> >> TCP proxies may perform local retransmission at the mobile edge.  In
> >> TCP, duplicated ACKs are detected and potentially concealed when the
> >> proxy retransmits a segment
> >
> > Again, TLS or SSH do not prevent this sort of hacks.
> >
> >> In addition to caching, various applications exist to provide data
> >> compression in order to conserve the life of the user's mobile data
> >> plan and optimize delivery over the mobile link
> >
> > I know that some mobile operators (see, in french,
> > <https://www.hteumeuleu.fr/la-compression-dimages-par-les-
> operateurs/>
> > ) apply a LOSSY compression without the user consent or even
> > knowledge. Again, if end-to-end encryption prevents this, this is a
> > very good reason to deploy encryption.
> >
> >> These regulations include Lawful Intercept, adherence to Codes of
> >> Practice on content filtering, and application of court order
> >> filters.  Such regulations assume network access to provide content
> >> filtering and accounting, as discussed below.
> >
> > It seems to me that RFC 1984 already replies to this reasoning.
> >
> >> This type of granular filtering could occur at the endpoint.
> >> However, the lack of ability to efficiently manage endpoints as a
> >> service reduces providers' ability to offer parental control.
> >
> > I would be specially unhappy if IETF were to publish a RFC with such a
> > sentence without follow-up comments. Filtering MUST be done at the
> > endpoint, otherwise it is not a service, it is censorship.
> >
> > If we assume that the subscriber wants parental control, then we must
> > conclude that he/she will have no problem sending the traffic to a
> > filtering proxy. No need to break encryption for that.
> >
> >> Some mobile carriers use HTTP header insertion (see section 3.2.1 of
> >> [RFC7230]) to provide information about their customers to third
> >> parties or to their own internal systems [Enrich].
> >
> > Again, this technique, which has very serious privacy consequences
> > (see the mentioned reference [Enrich] with for example Vodafone which
> > added the phone number and the IMEI in HTTP headers) MUST NOT be
> done
> > and, if encryption stops it, great.
> >
> > Editorial issues:
> >
> >> Currently, some mobile network service providers redirect the
> >> customer using HTTP redirect to a page that explains to those
> >> customers the reason for the blockage and the steps to proceed
> >
> > A mention of RFC 6108 would be cool here.
> >
> >> monitor incoming mail to remove SPAM
> >
> > Why is spam uppercased?





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