Counterintuitive Cryptography

There was a post on Twitter in the midst of the coronavirus COV-19 pandemic news this week, that caught my eye. It quoted an emergency room doctor in Los Angeles asking for help from the technology community, saying “we need a platform for frontline doctors to share information quickly and anonymously”. It went on to state the obvious requirement that “I need a platform where doctors can join, have their credentials validated and then ask questions of other frontline doctors”.

This is an interesting requirement that tell us something about the kind of digital identity that we should be building for the modern world instead of trying to find ways to copy passport data around the web. The requirement, to know what someone is without knowing who they are, is fundamental to the operation of a digital identity infrastructure in the kind of open democracy that we (ie, the West) espouse. The information sharing platform needs to know that the person answering a question has relevant qualifications and experience. Who that person is, is not important.

Now, in the physical world this is an extremely difficult problem to solve. Suppose there was a meeting of frontline doctors to discuss different approaches and treatments but the doctors wanted to remain anonymous for whatever reason (for example, they may not want to compromise the identity of their patients). I suppose the doctors could all dress up as ghosts, cover themselves in bedsheet and enter the room by presenting their hospital identity cards (through a slit in the sheet) with their names covered up by black pen. But then how would you know that the identity card belongs to the “doctor” presenting it? After all the picture on every identity card will be the same (someone dressed as a ghost) and you have no way of knowing whether it was their ID cards or whether they were agents of foreign powers, infiltrators hellbent on spreading false information to ensure the maximum number of deaths. The real-world problem of demonstrating that you have some particular credential or that you are the “owner” of a reputation without disclosing personal information is a very difficult problem indeed.

(It also illustrates the difficulty of trying to create large-scale identity infrastructure by using identification methods rather than authenticating to a digital identity infrastructure. Consider the example of James Bond, one of my favourite case studies. James Bond is masquerading as a COV-19 treatment physician in order to obtain the very latest knowledge on the topic. He walks up to the door of the hospital where the meeting is being held and puts his finger on the fingerprint scanner at the door… at which point the door loudly says “hello Mr Bond welcome back to the infectious diseases unit”. Oooops.)

In the virtual world this is quite a straightforward problem to solve. Let’s imagine I go to the doctors information sharing platform and attempt to login. The system will demand to see some form of credential proving that I am a doctor. So I take my digital hospital identity card out from my digital wallet (this is a thought experiment remember, none of the things actually exist yet) and send the relevant credential to the platform.

The credential is an attribute (in this case, IS_A_DOCTOR) together with an identifier for the holder (in this case, a public key) together with the digital signature of someone who can attest to the credential (in thsi case, the hospital the employs the doctor). Now, the information sharing platform can easily check the digital signature of the credential, because they have the public keys of all of the hospital and can extract the relevant attribute.

But how do they know that this IS_A_DOCTOR attribute applies to me and that I haven’t copied it from somebody else’s mobile phone? That’s also easy to determine in the virtual world with the public key of the associated digital identity. The platform can simply encrypt some data (anything will do) using this public key and send it to me. Since the only person in the entire world who can decrypt this message is the person with the corresponding private key, which is in my mobile phone’s secure tamper resistant memory (eg, the SIM or the Secure Enclave or Secure Element), I must be the person associated with the attribute. The phone will not allow the private key to be used to decrypt this message without strong authentication (in this case, let’s say it’s a fingerprint or a facial biometric) so the whole process works smoothly and almost invisibly: the doctor runs the information sharing platform app, the app invisibly talks to the digital wallet app in order to get the credential, the digital wallet app asks for the fingerprint, the doctor puts his or her finger on the phone and away we go.

Now the platform knows that I am a doctor but does not have any personally identifiable information about me and has no idea who I am. It does however have the public key and since the hospital has signed a digital certificate that contains this public key, if I should subsequently turn out to be engaged in dangerous behaviour, giving out information that I know to be incorrect, or whatever else doctors can do to get themselves disbarred from being doctors, then a court order against the hospital will result in them disclosing who I am. I can’t do bad stuff.

This is a good example of how cryptography can deliver some amazing but counterintuitive solutions to serious real-world problems. I know from my personal experience, and the experiences of colleagues at Consult Hyperion, that it can sometimes be difficult to communicate just what can be done in the world of digital identity by using what you might call counterintuitive cryptography, but it’s what we will need to make a digital identity infrastructure that works for everybody in the future. And, crucially, all of the technology exists and is tried and tested so if you really want to solve problems like this one, we can help right away.

The “isRecovered?” attribute

So far the tech giants seem to be the coronavirus winners, with a massive surge in digital communications and online orders. The impact on lift sharing companies is less clear.

The guidance from both Uber and Lyft says that if they are notified (by a public health authority) that a driver has COVID-19 they may temporarily suspend the driver’s account. It is not exactly clear how this would work.

That got us wondering whether digital identity systems, that we spend so much time talking about, could help. It seems to me there are two potential identity questions here:

1.       Is the driver who Uber or Lyft thinks it is?

2.       Does the driver have coronavirus?

The first question should be important to Uber and Lyft at any time. Ok, for the moment they want to be sure that they know who is driving to give them a better chance of knowing if the driver has the disease. But there are all sorts of other reasons why they might want to be sure that the driver is who they think it is – can the person legally drive for one.

The second question is harder. Just because the driver doesn’t have the virus today, doesn’t mean he or she won’t have it tomorrow. Maybe, perhaps the ability to share an isRecovered? attribute that says “I’ve recovered from the illness” would be useful when we start to see the light at the end of this tunnel we are entering. And the ability to share that anonymously might be helpful too – providing assurance to both driver and passenger.

All this to one side, the guidance from both Uber and Lyft outlines financial measures they are putting in place to provide security to drivers that self-isolate. That is a great example of responsibility providing the incentive and support required to allow their drivers to do the right thing.

KYC at a distance

We live in interesting times. Whatever you think about the Coronavirus situation, social distancing will test our ability to rely on digital services. And one place where digital services continue to struggle is onboarding – establishing who your customer is in the first place.  

One of the main reasons for this, is that regulated industries such as financial services are required to perform strict “know your customer” checks when onboarding customers and risk substantial fines in the event of compliance failings. Understandably then, financial service providers need to be cautious in adopting new technology, especially where the risks are not well understood or where regulators are yet to give clear guidance.

Fortunately, a lot of work is being done. This includes the development of new identification solutions and an increasing recognition that this is a problem that needs to be solved.

The Paypers has recently published its “Digital Onboarding and KYC Report 2020”. It is packed full of insights into developments in this space, features several Consult Hyperion friends and is well worth a look.

You can download the report here: https://thepaypers.com/reports/digital-onboarding-and-kyc-report-2020

Technology and Trust @ Money2020

Online trust is a pretty serious issue, but it’s not alway easy to quantify. We all understand that it is important, but what exactly is the value in pounds, shillings and pence (or whatever we will be using after Brexit) and how can we use that value to develop some business cases? It’s one thing to say (as you will often hear at conferences) that some technology or other can increase trust, but how do we know whether that means it is worth spending the money on it? At Consult Hyperion we have a very well-developed methodology, known as Structured Risk Analysis (SRA), for managing risk and directing countermeasure expenditures, but we need reasonable, informed estimates to make it work.

The specific case of online reviews might be one area where trust technologies can be assessed in a practical way. In the UK, the Competition and Markets Authority (CMA) estimates that a staggering £23bn a year of UK consumer spending is now influenced by online customer reviews and the consumer organisation Which has begun a campaign to stop fake reviews from misdirecting this spending. According to their press office, with “https://press.which.co.uk/whichpressreleases/revealed-amazon-plagued-with-thousands-of-fake-five-star-reviews/“, fake reviews are a very serious problem.

Unscrupulous businesses undoubtedly find fake reviews an incredibly useful tool. There are millions of examples we could use to illustrate this, but here is just one.”Asad Malik, 38, used fake reviews and photographs of secure car parks hundreds of miles away to trick customers into leaving their vehicles with him when they flew from Gatwick [Airport parking boss jailed for dumping cars in muddy fields].

So how can we use technology to make a difference here? When you read a review of an airport parking service, or a restaurant or a Bluetooth speaker, how can you even be sure (to choose the simplest example) that the reviewer purchased the product? Well, one possibility might be to co-opt the payment system: and this can be done in a privacy-enhancing way. Suppose when you pay the bill at a restaurant, and you have told your credit card provider that you are happy to be a reviewer, your credit card company sends you an unforgeable cryptographic token that proves you ate at the restaurant. Then, when you go to Tripadvisor or wherever, if you want to post a review of the restaurant, you have to provide such a token. The token would be cryptographically-blinded so that the restaurant and review-readers would not know who you are, so you could be honest, but they could be sure that you’ve eaten there.

Such “review tokens” are an obvious thing to store in digital wallets. You could easily imagine Calibra, to choose an obvious case study, storing these tokens and automatically presenting them when you log in to review sites. This would be a simple first step toward a reputation economy that would benefit consumers and honest service providers alike.

This is one of the cross-overs between payments and identity that we expect to be much discussed at Money20/20 in Las Vegas this week. I’ll be there with the rest of the Consult Hyperion team, so do come along to the great, great Digital Trust Track on Tuesday 29th and join in the discussions.

4 Essential Trends in Money for your Business

By Sanjib Kalita, Editor-in-Chief, Money20/20

This article was originally published on Money20/20.

We are in the midst of seismic societal changes of how people interact and transact.  Across societies, geographies and segments, digital is the new norm. Change has accelerated, placing greater value upon flexibility and speed. Historically, money and finance have been among the more conservative and slower changing parts of society, but this has changed dramatically over the past decade by viewing money as an instigator of change rather than a lagging indicator.

Whether you are a marketer in shining armor conquering new territory, a financial wizard casting spells upon the balance sheet, or the queen or king guiding the whole enterprise, here are 4 trends about money that you should keep in mind for your business.

Platforms are the new kingdoms

Platforms are the base upon which other structures can be built.  For example, App stores from Apple and Google provide the infrastructure for consumers to complete commercial transactions and manage finances through their mobile phones.  While these companies develop their own digital wallets, they also enable similar services from banks, retailers and other companies.  Building and maintaining the platform enables services that they would not have created on their own, like Uber or Lyft, which in turn, have created their own platforms.

Marketers trying to address customers’ needs can plug into platforms to broaden offerings or deepen engagement with target markets. Platform-based thinking implies that product and service design is ongoing and doesn’t stop with a product launch.  Jack Dorsey didn’t stop when he built the Square credit card reader.  The team went into lending with Square Capital.  They got into consumer P2P payments with Square Cash.  Their ecosystem has grown through partnerships with other companies as well as in-house development.

Digital Identities open the gates

How do your customers interact with you?  Do they need to create a username and password, or can they use a 3rd party system like Google or Facebook?  Are security services like two-factor authentication or biometrics used to protect credentials?  Is your company protecting customer identities adequately?  The importance of all of these questions is increasing and often the difference between being forced into early retirement by a massive data breach or surviving to continue to grow your business.

While identity management and digital security might not be top of mind for most marketers, they are table stakes for even the most basic future business.  History is full of tales of rulers successfully fighting off armies laying sieges on castles and fortresses, only to fail when another army gets access to a key for the back door.

Context rules the experience

Credit card transactions moved from predominantly being in-store, to e-commerce sites accessed from desktop computers, and now to mobile phones.  As the point-of-purchase expanded, so did the consumer use cases and thought processes. In tandem, mobile screens presents less information than desktop computer screens, which in turn presents less information than associates in a brick-and-mortar environment.  Companies best able to understand context and deliver the right user experience within these constraints will build loyal customer relationships.

Apps or services created for a different use cases on the same platform, such as Facebook and Messenger apps, can help achieve this. Banks and have different apps for managing accounts or for completing transactions or payments. On a desktop, you can access these services through a single interface but on the mobile, forcing users to select their use case helps present a streamlined experience on the smaller, more time-constrained mobile screen.  The use of additional data such as location, device, etc. can further streamline the experience. Marketers that don’t think about the context will lose the battle before it even begins.

Data is gold

While a marketer’s goal is to generate sales, data has become a value driver.  In the financial world, data about payments, assets and liabilities has become critical in how products and services are delivered.  PayPal, a fintech that began even before the word ‘fintech’, has recently been using payments data from their platform to help build a lending business for their customers.  Similarly, an SME lender named Kabbage has grown to unicorn status by using data from other sources to make smarter lending and pricing decisions.  In the payments industry, Stripe distilled a previously complex technology integration into a minimal data set, accessed via API, to easily build payments into new digital products and services.

Those that are able to harness the power of data will be able to predict what customers want and more effectively address their needs.  In some cases, it might be using data from within your enterprise or from other platforms for targeting, pricing or servicing decisions. In other cases, it might be using data to reimagine what your product or service is.

Looking for more insights on key trends in money? Hear from 400+ industry leaders at Money20/20 USA. Money20/20 USA will be held on October 27-30, 2019 at The Venetian Las Vegas. To learn more and attend visit us.money2020.com.

This article was originally published on www.money2020.com.

IdentityNORTH 2019

We recently attended IdentityNORTH in Toronto and as usual it was a great event to connect with colleagues and hear about what’s going in with digital identity initiatives in Canada. Aran, Krista and the entire IdentityNORTH team always put on an organized, well-run event with lots of great speakers and interesting sessions.

SCA: the end of merchant liability, and other authentication factors

The EBA’s recent Opinion on the elements of strong customer authentication under PSD2 was, apart from moving the goalposts on when SCA will be enforced, full of interesting information about what constitutes a valid SCA element. It closes some doors, opens others and ends any notion that merchants can take liability and not do SCA themselves.

Taking the final point first, there’s been a view that Article 74(2) of PSD2 permits merchants to carry on without implementing SCA as long as they take liability. We at Consult Hyperion have long argued that that is an optimistic and overly legalistic reading of the regulations and this has now been confirmed. The EBA states:


In addition, even if there were a liability shift to the payee or the payee’s PSP for failing to accept SCA, as articulated in Article74(2) of PSD2, this could not be considered an alleviation of PSPs’ obligation to apply SCA in accordance with and as specified in Article 97 of PSD2.

Basically, Article 97 takes precedence – PSPs (aka Issuers) must apply SCA so if the merchant chooses not to then rather than end up with a payment for which they’re liable they’ll end up with no payment at all. Which, you’d imagine, would rather miss the point of being a merchant.

Beyond this point the Opinion has lots of interest to say about inherence, possession and knowledge elements.

On inherence two points stand out. Firstly the Opinion unambiguously states that behavioural biometrics can be a valid factor: this opens up a world of possible low friction SCA, and we expect to see lots of innovation in this area. Secondly it states that 3DS-2 does not support inherence as none of the data points being gathered relate to biological or behavioural biometrics but – and we view this as important – 3DS-2 is a valid means of supporting SCA.

This is critical because the dynamic linking process behind 3DS-2 is not straightforward and there have been differences of opinion over whether this is compliant. Given that 3DS-2 appears to be the only game in town for CNP transactions having a statement that it’s OK is mighty important.

On possession, the EBA clarifies that OTP SMS is valid and also that mobile app based approaches can be – but only if the app is linked to the device. We’ve been arguing that this is obviously the case for a while, so it’s good to see this confirmed: although there are going to be a few app developers out there that need to revise their approaches pdq (we can help, of course!).

Also on possession the EBA has stated something that really should have been obvious to anyone taking more than a moderate interest in the topic – printed card details such as PAN and CVV or user ids and email addresses are not valid possession or knowledge elements. As a number of prominent industry players have been taking the opposite approach this could lead to some interesting developments in the coming weeks, particularly as the Opinion states that if the CVV is not printed on the card and is instead sent on a separate channel, then it is a valid knowledge element.

Overall, the analysis and discussion in the Opinion on valid SCA elements is welcome, if a trifle tardy. To be fair to the EBA, we don’t see anything in their analysis that a proper reading of the RTS wouldn’t have produced. However, it’s been clear for some time that many industry players have been making a highly liberal interpretation of the requirements usually based on a legal opinion. But PSD2 and the RTS are about principles, not rules: if you need advice on this you need to talk to the people who understand this stuff. Which, by the way, is us, not law firms.

The EBA blinks first …

EDIT: since posting this blog the UK’s FCA has confirmed our expectation that it won’t be enforcing SCA on the 14th September as long as the participants are aiming to comply with a soon to be announced migration plan. In the meantime it’s “working with the industry to develop a plan to migrate the industry to implement SCA for card payments in e-commerce as soon as possible”.  See: https://www.fca.org.uk/news/statements/fca-response-european-banking-authority%E2%80%99s-opinion-strong-customer-authentication

The doom-laden headlines appearing in the press have, it seems, worked and the EBA has decided to replace the 14th September deadline for the introduction of SCA with … another deadline. Only they won’t tell us what it is, presumably we have to figure it out for ourselves.  

So, let’s see what the EBA has done now …

Firstly, they haven’t actually changed the date as they can’t, it’s written into EU law. But given dire warnings of a collapse in online payments they’ve come up with a fudge:

The EBA therefore accepts that, on an exceptional basis and in order to avoid unintended negative consequences for some payment service users after 14 September 2019, CAs may decide to work with PSPs and relevant stakeholders, including consumers and merchants, to provide limited additional time to allow issuers to migrate to authentication approaches that are compliant with SCA, such as those described in this Opinion, and acquirers to migrate their merchants to solutions that support SCA.

https://eba.europa.eu/documents/

Let’s summarise that. National regulators – competent authorities (CAs) – may work with PSPs (Issuing and Acquiring banks) and unregulated actors (merchants, consumers) to agree to delay the introduction of SCA. Which presumably means unprepared merchants and confused consumers are breathing a sigh of relief. Unfortunately, as this is now in the hands of local regulators there’s no guarantee at all that this will be applied evenly, opening up the possibility that some countries will enforce and others (notably the UK and France) will not.

On top of that, there’s no guarantee that Issuers won’t apply SCA anyway, even if their local regulator permits them to not do so. So merchants who are unprepared may still find themselves suffering random declines. And, furthermore, if Acquirers haven’t implemented the necessary changes then even if the merchants are compliant they may still have transactions irrevocably declined.

Note also the “limited additional time” clause. Frankly, introducing SCA prior to the critical holiday shopping period was foolish anyway (but was an unintended consequence of the 18 month implementation period following the adoption of the RTS), so we can assume that the date will be pushed out at least into early or mid 2020. The EBA adds (but not in the actual Opinion):

In order to fulfil the objectives of PSD2 and the EBA of achieving consistency across the EU, the EBA will later this year communicate deadlines by which the aforementioned actors will have to have completed their migration plans.

And that’s the catch:

This supervisory flexibility is available under the condition that PSPs have set up a migration plan, have agreed the plan with their CA, and execute the plan in an expedited manner. CAs should monitor the execution of these plans to ensure swift compliance with the PSD2 and the EBA’s technical standards and to achieve consistency of authentication approaches across the EU.

Basically, Issuers and Acquirers need to publish what they’re going to do including how they’re going to communicate the requirements to consumers and merchants respectively. Quite how this is all going to be co-ordinated is unclear – no sensible merchant is going to disadvantage themselves by unilaterally turning on SCA when its competitors aren’t. Issuers may take the same approach, as they probably don’t want their cardholders switching to other banks: but there’s no requirement on them to do so.

The rest of the opinion focuses on the validity of various authentication factors. That’s interesting too, but we’ll look at the implications of it another day.

The one thing this does allow is for 3DS-2.2 to be made ready. That’s an advantage to smart merchants who can at least develop a proper, low friction SCA strategy. In the meantime, we’re looking forward to getting involved in lots of migration planning.

Digital Identity Alphabet Soup

We’ve been attending various identity conferences over the last few months, including KNOW 2019, the Internet Identity Workshop, and IdentityNORTH in North America, and EIC and Identity Week in Europe. One of the major themes that continues to stand out in all these events is the number of simultaneous initiatives going on around the world to create standards addressing various aspects of digital identity. It’s one of the reasons we created our 3-Domain Identity Model (see here for a refresher on 3DID), to help our clients navigate their way through all of this and to think about where they may play a role.

Identity Week

The opening keynote at identity week in London was given by Oliver Dowden, the Minister for implementation at the Cabinet office and therefore the person in charge of the digital transformation of government. At Consult Hyperion we think digital identity is central to digital transformation of government (and the digital transformation of everything else, for that matter) so I was looking forward to hearing the UK government’s vision for digital identity. I accompanied the Minister on his visit to the IDEMIA stand where he was shown a range of attractive burgundy passports.

In his keynote, the Minister said that the UK is seen as being at the cutting edge of digital identity and that GOV.UK Verify is at the heart of that success.

(For foreign visitors, perhaps unfamiliar with this cutting edge position, a spirit of transparency requires me to note that back on 9th October 2016, Mr. Dowden gave written statement HCWS978 to Parliament, announcing that the government was going to stop funding Verify after 18 months with the private sector responsible for funding after that.)

Given that the government spends around £1.5 billion per annum on “identity, fraud, error, debt, how much identity costs to validate, and how much proprietary hardware and software bought”, it’s obviously important for them to set an effective strategy. Now, members of the public, who don’t really know or care about digital ID might be saying to themselves, “why can’t we just use ‘sign in with Apple’ to do our taxes?”, and this is a good point. Even if they are not saying it right now, they’ll be saying it soon as they get used to Apple’s mandate that all apps that allow third-party sign-in must support it.

Right now you can’t use a GOV.UK Verify Identity Provider to log into your bank or any other private sector service provider. But in his speech the Minister said that he looks forward to a time when people can use a single login to “access their state pension and the savings account” and I have to say I agree with him. Obviously you’d want a different single login for gambling and pornography, but that’s already taken care of as, according to Sky News, “thanks to its ill-conceived porn block, the government has quietly blundered into the creation of a digital passport – then outsourced its development to private firms, without setting clear limits on how it is to be used”. One of these firms runs the world’s largest pornography site, Pornhub, so I imagine they know a thing or two about population-scale identity management.

Back to the Minister’s point though. Yes, it would be nice to have some sort of ID app on my phone and it would be great if my bank and the HMRC and Woking Council and LinkedIn would all let me log in with this ID. The interesting question is how you get to this login. Put a PIN in that and we’ll come back to it later.

The Minister made three substantive points in the speech. He talked about:

  • The creation of a new Digital Identity Unit, which is a collaboration between DCMS and Cabinet Office. The Unit will help foster co-operation between the public and private sector, ensure the adoption of interoperable standards, specification and schemes, and deliver on the outcome of the consultation.
  • A consultation to be issued in the coming weeks on how to deliver the effective organisation of the digital identity market. Through this consultation the government will work with industry, particularly with sectors who have frequent user identity interactions, to ensure interoperable ‘rules of the road’ for identity.
  • The start of engagement on the commercial framework for consuming digital identities from the private sector for the period from April 2020 to ensure the continued delivery of public services. The Government Digital Service will continue to ensure alignment of commercial models that are adopted by the developing identity market to build a flourishing ecosystem that delivers value for everyone.

The Minister was taken away on urgent business and therefore unable to stay for my speech, in which I suggested that the idea of a general-purpose digital identity might be quite a big bite to take at the problem. So it would make sense to look at who else might provide the “digital identities from the private sector” used for the delivery of public services. Assuming the current GOV.UK Verify identities fail to gain traction in the private sector, then I think there are two obvious private sector coalitions that might step in to do this for the government: the big banks and the big techs.

For a variety of reasons, I hope that the big banks are able to come together to respond to the comments of Mark Carney, the Governor of the Bank of England, on the necessity for a digital identity in the finance sector to work with the banks to develop some sort of financial services passport. I made some practical suggestions about this earlier in the year and have continued to discuss the concept with potential stakeholders. I think it stacks up, but we’ll have to see how things develop.

On the other hand, if the banks can’t get it together and the big techs come knocking, they are already showing off their solutions. I’ll readily admit that when the Minister first said “private sector identities”, the first thought to flash across my brain was “Apple”. But I wouldn’t be at all surprised to go over to the HMRC web site fairly soon to find a “log in with Amazon” and “log in with Apple” next a button with some incomprehensible waffle about eIDAS that I, and most other normal consumers I’m sure, will simply ignore.

How do you use Apple ID to log into the Inland Revenue? Easy: you log in as you do now after sending off for the password and waiting for it to come in the post and that sort of thing and then once you are connected tell them the Apple ID that you want to use in the future. If you want to be “jackdaniels@me.com” or whatever, it doesn’t matter. It’s just an identifier for the Revenue to recognise you in the future. Then next time you go to the Inland Revenue, you log in as jackdaniels@me.com, something pops up on your iPhone and you put your thumb on it or look at it, and bingo you logged in to fill out your PAYE.


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