Lockstep

Mobile: +61 (0) 414 488 851
Email: swilson@lockstep.com.au

Postcard from Monterey 2 #CISmcc

Second Day Reflections from CIS Monterey.

Follow along on Twitter at #CISmcc (for the Monterey Conference Centre).

The attributes push

At CIS 2013 in Napa a year ago, several of us sensed a critical shift in focus amongst the identerati - from identity to attributes. OIX launched the Attributes Exchange Network (AXN) architecture, important commentators like Andrew Nash were saying, 'hey, attributes are more interesting than identity', and my own #CISnapa talk went so far as to argue we should forget about identity altogether. There was a change in the air, but still, it was all pretty theoretical.

Twelve months on, and the Attributes push has become entirely practical. If there was a Word Cloud for the NSTIC session, my hunch is that "attributes" would dominate over "identity". Several live NSTIC pilots are all about the Attributes.

ID.me is a new company started by US military veterans, with the aim of improving access for the veterans community to discounted goods and services and other entitlements. Founders Matt Thompson and Blake Hall are not identerati -- they're entirely focused on improving online access for their constituents to a big and growing range of retailers and services, and offer a choice of credentials for proving veterans bona fides. It's central to the ID.me model that users reveal as little as possible about their personal identities, while having their veterans' status and entitlements established securely and privately.

Another NSTIC pilot Relying Party is the financial service sector infrastructure provider Broadridge. Adrian Chernoff, VP for Digital Strategy, gave a compelling account of the need to change business models to take maximum advantage of digital identity. Broadridge recently annoucned a JV with Pitney Bowes called Inlet, which will enable the secure sharing of discrete and validated attributes - like name, address and social security number - in an NSTIC compliant architecture.

Mind bending

Yesterday I said in my CISmcc diary that I hoped to change my mind at #CISmcc about something, and half way through Day 2, I was delighted it was already happening. I've got a new attitude about NSTIC.

Over the past six months, I had come to fear http://www.nist.gov/nstic/">NSTIC had lost its way. It's hard to judge totally accurately when lurking on the webcast from Sydney (at 4:00am) but the last plenary seemed pedestrian to me. And I'm afraid to say that some NSTIC committees have got a little testy. But today's NSTIC session here was a turning point. Not only are there a number or truly exciting pilots showing real progress, but Jeremy Grant has credible plans for improving accountability and momentum, and the new technology lead Paul Grassi is thinking outside the box and speaking out of school. The whole program seems fresh all over again.

In a packed presentation, Grassi impressed me enormously on a number of points:

  • Firstly, he advocates a pragmatic NSTIC-focused extension of the old US government Authentication Guide NIST SP 800-63. Rather than a formal revision, a companion document might be most realistic. Along the way, Grassi really nailed an issue which we identity professionals need to talk about more: language. He said that there are words in 800-63 that are "never used anywhere else in systems development". No wonder, as he says, it's still "hard to implement identity"!
  • Incidentally I chatted some more with Andrew Hughes about language; he is passionate about terms, and highlights that our term "Relying Party" is an especially terrible distraction for Service Providers whose reason-for-being has nothing to do with "relying" on anyone!
  • Secondly, Paul Grassi wants to "get very aggressive on attributes", including emphasis on practical measurement (since that's really what NIST is all about). I don't think I need to say anything more about that than Bravo!
  • And thirdly, Grassi asked "What if we got rid of LOAs?!". This kind of iconoclastic thinking is overdue, and was floated as part of a broad push to revamp the way government's orthodox thinking on Identity Assurance is translated to the business world. Grassi and Grant don't say LOAs can or should be abandoned by government, but they do see that shoving the rounded business concepts of identity into government's square hole has not done anyone much credit.

Just one small part of NSTIC annoyed me today: the persistent idea that federation hubs are inherently simpler than one-to-one authentication. They showed the following classic sort of 'before and after' shots, where it seems self-evident that a hub (here the Federal Cloud Credential Exchange FCCX) reduces complexity. The reality is that multilateral brokered arrangements between RPs and IdPs are far more complex than simple bilateral direct contracts. And moreover, the new forms of agreements are novel and untested in real world business. The time and cost and unpredictability of working out these new arrangements is not properly accounted for and has often been fatal to identity federations.

IMG 5412 BEFORE cropped
IMG 5413 AFTER cropped


The dog barks and this time the caravan turns around

One of the top talking points at #CISmcc has of course been FIDO. The FIDO Alliance goes from strength to strength; we heard they have over 130 members now (remember it started with four or five less than 18 months ago). On Saturday afternoon there was a packed-out FIDO show case with six vendors showing real FIDO-ready products. And today there was a three hour deep dive into the two flagship FIDO protocols UAF (which enables better sharing of strong authentication signals such that passwords may be eliminated) to and U2F (which standardises and strengthens Two Factor Authentication).

FIDO's marketing messages are improving all the time, thanks to a special focus on strategic marketing which was given its own working group. In particular, the Alliance is steadily clarifying the distinction between identity and authentication, and sticking adamantly to the latter. In other words, FIDO is really all about the attributes. FIDO leaves identity as a problem to be addressed further up the stack, and dedicates itself to strengthening the authentication signal sent from end-point devices to servers.

The protocol tutorials were excellent, going into detail about how "Attestation Certificates" are used to convey the qualities and attributes of authentication hardware (such as device model, biometric modality, security certifications, elapsed time since last user verification etc) thus enabling nice fine-grained policy enforcement on the RP side. To my mind, UAF and U2F show how nature intended PKI to have been used all along!

Some confusion remains as to why FIDO has two protocols. I heard some quiet calls for UAF and U2F to converge, yet that would seem to put the elegance of U2F at risk. And it's noteworthy that U2F is being taken beyond the original one time password 2FA, with at least one biometric vendor at the showcase claiming to use it instead of the heavier UAF.

Surprising use cases

Finally, today brought more fresh use cases from cohorts of users we socially privileged identity engineers for the most part rarely think about. Another NSTIC pilot partner is AARP, a membership organization providing "information, advocacy and service" to older people, retirees and other special needs groups. AARP's Jim Barnett gave a compelling presentation on the need to extend from the classic "free" business models of Internet services, to new economically sustainable approaches that properly protect personal information. Barnett stressed that "free" has been great and 'we wouldn't be where we are today without it' but it's just not going to work for health records for example. And identity is central to that.

There's so much more I could report if I had time. But I need to get some sleep before another packed day. All this changing my mind is exhausting.

Cheers again from Monterey.

Posted in Security, Privacy, PKI, Language, Identity, Federated Identity, e-health

Bob is dead

With apologies to Friedrich Nietzsche. The hero of many a crypto folk tale Bob is dead, and we have killed him.

We now know that in PKI, Alice's Relying Party is almost always a machine and not a human being. The idea that two strangers would use PKI to work out whether or not to trust one another was deeply distracting and led to the complexity that in the main stymied early PKI.

All of which might be academic except the utopian idea persists that identity frameworks can and should underpin stranger-to-stranger e-business. With NSTIC for instance I fear we are sleep walking into a repeat of Big PKI, when we could be solving a simpler problem: the robust and bilateral presentation of digital identity data in established contexts, without changing the existing relationships that cover almost all serious transactional business.

The following is an extract from a past paper of mine, "Public Key Superstructure" which was presented to the NIST IDTrust Workshop in 2008. There I examine the shortfalls and pitfalls of using signed email as a digital signature archetype.

E-mail not a killer application for PKI

A total lack of real applications would explain why e-mail became by default the most talked about PKI application. Many PKI vendors to this day continue to illustrate their services and train their users with imaginary scenarios where our heroes Alice and Bob breathlessly exchange signed e-mails. Like the passport metaphor, e-mail seems easily understood, but it manifestly has not turned out to be a ‘killer application’, and worse still, has contributed to a host of misunderstandings.

The story usually goes go that Alice has received a secure e-mail from stranger Bob and wishes to work out if he is trustworthy. She double clicks on his digital signature and certificate in order to identify his CA. And now the fun begins. If Alice is not immediately trusting of the CA (presumably by reputation) then she is expected to download the CP and CPS, read them, and satisfy herself that the registration processes and security standards are adequate for her needs.

Does this sort of rigmarole have any parallel in the real world? A simple e-mail with no other context is closely equivalent to a letter or fax sent on plain white paper. Under what circumstances should we take seriously a message sent on plain paper from a stranger, even if we could track down their name?

In truth, the vast majority of serious communications occurs not between strangers but in a rich existing context, where the receiver has already been qualified in some way by the sender as likely being the right party to contact. In e-business, routine transactions are not usually conducted by e-mail but instead use special purpose software or dedicated websites with purpose built content. Thus we see most of the digital signature action in cases such as e-prescriptions, customs broking, trade documentation, company returns, patent filing and electronic conveyancing.

Several important simplifying assumptions flow from the fact that most e-business has a rich context, and these should be heeded when planning PKI:

Emphasise straight-through processing

In spite of the common worked example of Alice and Bob exchanging e-mails, the receiver of most routine transactions – such as payment instructions, tax returns, medical records, import/export declarations, or votes – is not a human but instead is a machine. The notion that a person will examine digital certificates and chase down the CA and its practices is simply false in the vast majority of cases. One of PKI’s great strengths is the way it aids straight-through processing, so it has been a great pity that vendors, through their training and marketing materials, have stressed manual over automatic processing.

Play down Relying Party Agreements

The sender and receiver of digitally signed transactions are hardly ever un-related. This is in stark contrast to orthodox legal analyses of PKI which foundered on the supposed lack of contractual privity between Relying Party and CA. For example the Australian Government’s extensive investigation into legal liability in digital certificates after 76 pages still could not reach a firm conclusion about whether a “CA may owe a duty of care to a [Relying Party] who is not known to the CA” [http://www.egov.vic.gov.au/pdfs/publication_utz1508.pdf]. The fact is, this sort of scenario is entirely academic and should never have been given the level of attention that it was. The idea of a “Relying Party Agreement” to join in contract the RP and the CA is moot in all “closed” e-business settings where PKI in thriving. It is this lesson that needs to be generalised by PKI regulators, not the hypothetical model of “open” PKI where all parties are strangers.

Play down certificate path discovery

The fact that in real life, parties are transacting in the context of some explicit scheme, means that the receiver’s software can predict the type of certificate that will most often be used by senders. For instance, when doctors are using e-prescribing software, there is not going to be a wide choice of certificate options; indeed, the appropriate scheme root keys and certificates for authenticating a whole class of doctors will likely be installed at both the sending and receiving ends, at the same time that the software is. When a doctor writes a prescription, their private key can be programmatically selected by their client and invoked to create a digital signature, according to business rules enshrined in the software design. And when such a transaction is received, the software of the pharmacist (or insurance company, government agency etc.) will similarly ‘know’ by design which classes of certificates are expected to verify the digital signature. All this logic in most transaction systems can be settled at design time, which can greatly simplify the task of certificate path discovery, or eliminate it altogether. In most systems it is straightforward for the sender’s software to attach the whole certificate chain to the digital signature, safe in the knowledge that the receiver’s software will be configured with the necessary trust anchors (i.e. Root CA certificates) with which to parse the chain.

Posted in PKI, Identity, Federated Identity

An authentication family tree

How do we make best sense of the bewildering array of authenticators on the market? Most people are familiar with single factor versus two factor, but this simple dichotomy doesn’t help match technologies to applications. The reality is more complex. A family tree like the one sketched here may help navigate the complexity.

Different distinctions define various branch points. The first split is between what I call Transient authentication (i.e. access control) which tells if a user is allowed to get at a resource or not, and Persistent authentication, which lets a user leave a lasting mark (i.e. signature) on what they do, such as binding electronic transactions.

Working our way up the Transient branch, we see that most access controls are based either on shared secrets or biometrics. Dynamic shared secrets change with every session, either in a series of one time passwords or via challenge-response.

On the biometric branch, we should distinguish those traits that can be left behind inadvertently in the environment and are more readily stolen. The safer biometrics are “clean” and leave no residue. Note that while the voice might be recorded without the speaker’s knowledge, I don't see it as a residual biometric in practice because voice recognition solutions usually use dynamic phrases that resist replay.

For persistent authentication, the only practical option today is PKI and digital signatures, technology which is available in an increasingly wide range of forms. Embedded certificates are commonplace in smartcards, cell phones, and other devices.

The folliage in the family tree indicates which technologies I believe will continue to thrive, and which seem more likely to be dead-ends.

I'd appreciate feedback. Is this useful? Does anyone know of other taxonomies?

Posted in Security, PKI, Biometrics

Simpler PKI is on the cards

PKI has a reputation for terrible complexity, but it is actually simpler than many mature domestic technologies.

PKI stack pics 110121 eye candy cropped

It's interesting to ponder why PKI got to be (or look) so complicated. There have been at least two reasons. First, the word is frequently taken to mean the original overblown "Big PKI" general purpose identification schemes, with their generic and context-free passport grade ID checks, horrid user agreements and fine print. Yet there are alternative ways to deploy public key technology in closed authentication schemes, and indeed that is where it thrives; see http://lockstep.com.au/library/pki. Second, there is all that gory technical detail foisted on lay people in the infamous "PKI 101" sessions. Typical explanations start with a tutorial on asymmetric cryptography even before they tell you what PKI is for. ]

I've long wondered what it is about PKI that leads its advocates to train people into the ground. Forty-odd years ago when introducing the newfangled mag stripe banking card, I bet the sales reps didn't feel the need to explain electromagnetism and ferric oxide chemistry.

This line of thought leads to fresh models for 'domesticating' PKI by embedding it in plastic cards. By re-framing PKI keys and certificates as being means to an end and not ends in themselves, we can also:

― identify dramatically improved supply chains to deliver PKI's benefits
― re-cast the traditionally difficult business model for CAs, and
― demystify how PKI can support a plurality of IDs and apps.

Consider the layered complexity of the conventional plastic card, and the way the layers correspond to steps in the supply chain. At its most basic level, the card is based on solid state physics and Maxwell's Equations for electromagnetism. These govern the properties of ferric oxide crystals, which are manufactured as powders and coated onto bulk tape by chemical companies like BASF and 3M. The tape is applied to blank cards, which are distributed to different schemes for personalisation. Usually the cards are pre-printed in bulk with artwork and physical security features specific to the scheme. In general, personalisation in each scheme starts with user registration. Data is written to the mag stripe according to one of a handful of coding standards which differ a little bwteen banks, airlines and other niches. The card is printed or embossed, and distributed.

Lockstep PKI Tech Stack Ferric

The variety of distinct schemes using magnetic stripe cards is almost limitless: bank cards, credit cards, government entitlements, health insurance, clubs, loyalty cards, gift cards, driver licences, employee ID, universities, professional associations etc etc. They all use the same ferromagnetic components delivered through a global supply chain, which at the lower layers is very specialised and delivered by only a handful of companies.

And needless to say, hardly anyone needs to know Maxwell's Equations to make sense of a mag stripe card.

The smartcard supply chain is very similar. The only technical difference is the core technology used to encode the user information. The theoretical foundations are cryptography instead of electromagnetism, and instead of bulk ferric oxide powders and tapes, specialist semiconductor companies fabricate the ICs and preload them with firmware. From that point on, the smartcard and mag stripe card supply chains overlap. In fact the end user in most cases can't tell the difference between the different generations of card technologies.

Lockstep PKI Tech Stack Crypto

Smartcards (and their kin: SIMs, USB keys and smartphones) are the natural medium for deploying PKI technology.

Re-framing PKI deployment like this ...

― decouples PK technology from the application and scheme layers, and tames the technical complexity; it shows where to draw the line in "PKI 101" training

― provides a model for transitioning from conventional "id" technology to PKI with minimum disruption of current business processes and supplier arrangements

― shows that it's perfectly natural for PKI to be implemented in closed communities of interest (schemes) and takes us away from the unhelpful orthodox Big PKI model

― suggests new "wholesale" business models for CAs; historically CAs found it difficult to sell certificates direct, but a clearly superior model is to provide certificates into the initialisation step

― demonstrates how easy to use PKI should be; that is, exactly as easy to use as the mag stripe card.

I once discussed this sort of bulk supply chain model at a conference in Tokyo. Someone in the audience asked me how many CAs I thought were needed worldwide. I said maybe three or four, and was greeted with incredulous laughter. But seriously, if certificates are reduced to digitally signed objects that bind a parcel of cardholder information to a key associated with a chip, why shouldn't certificates be manufactured by a fully automatic CA service on an outsourced managed service basis? It's no different from security printing, another specialised industry with the utmost "trust" requirements but none of the weird mystique that has bedevilled PKI.

Posted in PKI, Identity

No such thing as a passport

What do you call it when a metaphor or analogy outgrows the word it is based on, thus co-opting that word to mean something quite new? Metaphors are meant to clarify complex concepts by letting people think of them in simpler terms. But if the detailed meaning is actually different, then the metaphor becomes misleading and dangerous.

I'm thinking of the idea of the electronic passport. Ever since the early days of Big PKI, there's been the beguiling idea of an electronic passport that will let the holder into all manner of online services and enable total strangers to "trust" one another online. Later Microsoft of course even named their digital identity service "Passport", and the word is still commonplace in discussing all manner of authentication solutions.

The idea is that the passport allows you to go wherever you like.

Yet there is no such thing.

A real world passport doesn't let you into any old country. It's not always sufficient; you often need a visa. You can't stay as long as you like in a foreign place. Some countries won't let you in at all if you carry the passport of an unfriendly nation. You need to complete a landing card and customs declarations specific to your particular journey. And finally, when you've got to the end of the arrivals queue, you are still at the mercy of an immigration officer who has the discretion to turn you away. As with all business, there is so much more going on here than personal identity.

So in the sense of the meaning important to the electronic passport metaphor, the "real" passport doesn't actually exist!

The simplistic notion of electronic passport is really deeply unhelpful. The dream and promise of general purpose digital certificates is what derailed PKI, for they're unwieldy, involve unprecedented mechanisms for conferring open-ended "trust", and are rarely useful on their own (ironically that's also a property of real passports). Think of the time and money wasted chasing the electronic passport when all along PKI technology was better suited to closed transactions. What matters in most transactions is not personal identity but rather, credentials specific to the business context. There never has been a single general purpose identity credential.

And now with "open" federated identity frameworks, we're sleep-walking into the same intractable problems, all because people have been seduced by a metaphor based on something that doesn't exist.

The well initiated understand that the Laws of Identity, OIX, NSTIC and the like involve a plurality of identities, and multiple attributes tuned to different contexts. Yet NSTIC in particular is still confused by many with a single new ID, a misunderstanding aided and abetted by NSTIC's promoters using terms like "interoperable" without care, and by casually 'imagining' that a student in future will log in to their bank using their student card .

Words are powerful and they're also malleable. Some might say I'm being too pedantic sticking to the traditional reality of the "passport". But no. It would be OK in my opinion for "passport" to morph into something more powerful and universal -- except that it can't. The real point in all of this is that multiple identities are an inevitable consequence of how identities evolve to suit distinct business contexts, and so the very idea of a digital passport is a bit delusional.

Posted in Security, PKI, Language, Internet, Identity, Culture