Re: [GNAP] Consensus Call on Continuation Request

Dave Tonge <dave.tonge@moneyhub.com> Tue, 15 December 2020 13:58 UTC

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From: Dave Tonge <dave.tonge@moneyhub.com>
Date: Tue, 15 Dec 2020 14:58:24 +0100
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To: Fabien Imbault <fabien.imbault@gmail.com>
Cc: Torsten Lodderstedt <torsten@lodderstedt.net>, Dick Hardt <dick.hardt@gmail.com>, txauth gnap <txauth@ietf.org>, Justin Richer <jricher@mit.edu>, Stephen Moore <srmoore@gmail.com>
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Subject: Re: [GNAP] Consensus Call on Continuation Request
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A string that can be used to identify the grant in order to get its latest
status, continue, update, revoke.

Internally an AS will have an identifier for a grant
Internally an RC will have an identifier for a grant
Why can't we just make this explicit in the protocol.

In the current world of OAuth 2 we have
 - refresh token
 - PAR
 - device_code in OAuth Device Flow
 - grant management
<https://bitbucket.org/openid/fapi/src/master/Financial_API_Grant_Management.md>
 - auth_req_id in CIBA
 - "consent ids" in proprietary APIs

They all somehow represent the "grant", but the fact that most of them are
tacked on to the existing protocol, causes problems.

I really like the fact that GNAP has the current "continue" endpoint built
into the spec - allowing "grant management" to be a first class feature of
the protocol. But I don't like the fact that an ephemeral rotating token is
the identifier for the grant.

A failed network request can mean that the RC no longer has access to
manage a grant - in fact they may not even be able to reference it when
starting a new grant as they may only have access to an expired access
token that the AS may not accept. This seems unnecessarily brittle.

On Tue, 15 Dec 2020 at 13:52, Fabien Imbault <fabien.imbault@gmail.com>
wrote:

> Ok, could you be more specific as to what you'd expect for the persistent
> identifier ?
> Thanks
> Fabien
>
> On Tue, Dec 15, 2020 at 1:50 PM Dave Tonge <dave.tonge@moneyhub.com>
> wrote:
>
>> The persistent identifier is not a different issue, the current access
>> token is used to reference an existing grant
>> <https://github.com/ietf-wg-gnap/gnap-core-protocol/blob/main/draft-ietf-gnap-core-protocol.md#referencing-an-existing-grant-request-request-existing>
>>
>>
>> It may not be more difficult for a client to *use* an access token at
>> the AS / RS. But there is definitely an overhead on the client to
>> *manage* this separate access token.
>>
>>
>>
>> On Tue, 15 Dec 2020 at 12:10, Fabien Imbault <fabien.imbault@gmail.com>
>> wrote:
>>
>>> I think we always said the access token was different, and handled as a
>>> bound token.
>>>
>>> But it doesn't mean it's more difficult for the client that already
>>> needs to be able to handle tokens anyway (bearer or not, both cases could
>>> occur). It's mostly consolidating the logic.
>>>
>>> You're anticipating a lot of issues which have no specific reason to
>>> occur, such as "can't be used with the token management APIs?". The
>>> management API is part of the same general flow.
>>> Anticipating issues with rotation is useful, but there are also many
>>> ways it can be hard to manage through a stateful approach too. And
>>> fundamentally, having everything in a common model (both for the internals
>>> of the AS and for the API calls) will help improve by a large margin what
>>> is probably the weakest point in today's infrastructure. But it's early to
>>> be definitive as to the downstream impact either way.
>>>
>>> As for a persistent identifier instead of a continuation API, and
>>> generally the end of your message, it's a totally unrelated issue to this
>>> PR, so I suggest we don't discuss that here, but in a separate issue if
>>> needed.
>>>
>>> Fabien
>>>
>>> On Tue, Dec 15, 2020 at 11:08 AM Dave Tonge <dave.tonge@moneyhub.com>
>>> wrote:
>>>
>>>> So we've established that this is a different access token, that
>>>> requires different handling at the client. So keeping it could cause more
>>>> confusion?
>>>>
>>>> As an RC, I will have to store the continue `uri` as although it could
>>>> be static it could also be dynamic. Why do I need to store an access token
>>>> as well. It brings me no benefit as an RC, in fact it brings more
>>>> complexity. As I will now need to manage multiple types of tokens with
>>>> different lifecycles:
>>>>
>>>> *Continuation token*
>>>>   - can only be used at the continue endpoint (the name of which is
>>>> confusing as I can use this endpoint to revoke a grant or get metadata on
>>>> the grant).
>>>>  - may be rotated each time it is used, or may not be
>>>>  - provided in the `continue` section of the response
>>>>  - must be sender-constrained
>>>>  - can't be used with the token management APIs?
>>>>  - can be used to identify the grant when making subsequent grants
>>>>
>>>> *Access token(s) to use at RS*
>>>>   - can only be used at the specified RS
>>>>   - may be sender constrained
>>>>   - when used at the RS, will not result in rotation
>>>>
>>>> From my perspective, most use-cases will require the RC to have a
>>>> persistent identifier for the grant. Why not bring this into the protocol
>>>> and let the AS provide this persistent identifier (through the form of the
>>>> continue uri). Using a rotating access token as a persistent identifier
>>>> doesn't seem like the right choice.
>>>>
>>>> I see no security benefit to having the continuation access token. It
>>>> doesn't matter if the continue uri leaks as it is useless without an
>>>> accompanying signature, i.e. any security benefit of having an access token
>>>> is already provided by having a signature.
>>>>
>>>> The only benefits that I can see are:
>>>>  - If the AS wants to be fully stateless, then you can encode more data
>>>> in a token than in a uri
>>>>  - If the AS wants to have a static endpoint for CRUD operations on the
>>>> grant
>>>>  - To allow the AS to identity a previous grant
>>>>
>>>> If we dropped the access token for the continue endpoint and rather
>>>> mandated a dynamic uri this would make things conceptually easier to
>>>> understand, easier for the RC to implement, easier to debug and less chance
>>>> of errors when rotating tokens (i.e. race conditions could be quite likely
>>>> if the AS always rotates the token)
>>>>
>>>> *One-off grant with no continuation or ongoing management:*
>>>> RC sends signature and metadata, no `continue` response provided,
>>>> therefore no grant management possible
>>>>
>>>> *Grant with ongoing management*
>>>> RC sends signature and metadata, AS responds with a continue uri that
>>>> has these purposes:
>>>>  - can be used by the RC to continue/update, read or revoke the grant
>>>>  - can be used by the RC when making a new grant to identify the
>>>> previous grant
>>>>
>>>> As an RC the only permanent items I need to store are:
>>>>  - the continue uri associated with the grant
>>>>  - any access tokens I receive for the grant
>>>>
>>>> Dave
>>>>
>>>> On Tue, 15 Dec 2020 at 10:11, Fabien Imbault <fabien.imbault@gmail.com>
>>>> wrote:
>>>>
>>>>> Hi Torsten,
>>>>>
>>>>> You're right on both accounts.
>>>>> - for the first remark, it fits quite nicely the init request  /
>>>>> continuation pattern
>>>>> - for the second remark, it is a sort of handle for the
>>>>> continuation request, which will eventually lead to the issuance or refresh
>>>>> of standard access tokens
>>>>>
>>>>> Having a specific name is a possibility, I actually suggested that too
>>>>> at some point.
>>>>>
>>>>> Fabien
>>>>>
>>>>> On Tue, Dec 15, 2020 at 9:50 AM Torsten Lodderstedt <
>>>>> torsten@lodderstedt.net> wrote:
>>>>>
>>>>>> Hi Fabien,
>>>>>>
>>>>>> > Am 12.12.2020 um 12:06 schrieb Fabien Imbault <
>>>>>> fabien.imbault@gmail.com>:
>>>>>> >
>>>>>> > Hi,
>>>>>> >
>>>>>> > On the contrary your feedback is most welcome.
>>>>>> >
>>>>>> > It doesn't accept any token, it needs the particular token as
>>>>>> described in 3.1 and which is not a bearer token (that's what the "key" :
>>>>>> true parameter is supposed to convey).
>>>>>> >
>>>>>> > Let us know if you need more clarifications.
>>>>>>
>>>>>> Thanks for the clarification. I think only accepting this kind of
>>>>>> token at the continuation is a good idea otherwise the AS would need to be
>>>>>> able to parse and understand all sorts of access tokens.
>>>>>>
>>>>>> Conceptually, I like the idea to treat the continuation as another
>>>>>> kind of resource. However, here are some observations I want to share with
>>>>>> you:
>>>>>> - This resource is different as it will issue other access tokens (of
>>>>>> this kind) to be used in subsequent continuation requests. This requires
>>>>>> different handing on the client side.
>>>>>> - This access token (if I understand correctly) is (or at least feels
>>>>>> like) a handle for the underlying grant. So it is kind of the super access
>>>>>> token to obtain other access tokens.
>>>>>>
>>>>>> I would consider using a different term to refer to this special
>>>>>> access token, grant token or grant handle for example, in order to prevent
>>>>>> confusion.
>>>>>>
>>>>>> best regards,
>>>>>> Torsten.
>>>>>>
>>>>>>
>>>>>> >
>>>>>> > Best
>>>>>> > Fabien
>>>>>> >
>>>>>> > Le sam. 12 déc. 2020 à 11:33, Torsten Lodderstedt <
>>>>>> torsten@lodderstedt.net> a écrit :
>>>>>> > Hi all,
>>>>>> >
>>>>>> > I didn’t follow GNAP closely so bear with me if me question seems
>>>>>> naive.
>>>>>> >
>>>>>> > After having skimmed through the current draft and the PR, I‘m not
>>>>>> sure whether the continuation requests accepts any access token issued to
>>>>>> the RC or the particular access token returned in the „continue“ element in
>>>>>> section 3.1..
>>>>>> >
>>>>>> > Can you please shed some light on this?
>>>>>> >
>>>>>> > kind regards,
>>>>>> > Torsten.
>>>>>> >
>>>>>> >> Am 12.12.2020 um 03:35 schrieb Fabien Imbault <
>>>>>> fabien.imbault@gmail.com>:
>>>>>> >>
>>>>>> >> 
>>>>>> >> You're completely right. Allowing the dev to be lazy is a very
>>>>>> good thing in general, because it's what we know will work :-)
>>>>>> >>
>>>>>> >> Le sam. 12 déc. 2020 à 03:15, Stephen Moore <srmoore@gmail.com> a
>>>>>> écrit :
>>>>>> >> Hi Fabien,
>>>>>> >>
>>>>>> >> For #3) Even after I typed out the hypothetical attack, that was
>>>>>> sort of in the back of my mind, it isn't a huge risk there. So I actually
>>>>>> agree with Dick there. Something doesn't sit right with me for the unique
>>>>>> URL solution, so I don't like it and came up with a hypothetical that seems
>>>>>> like it could be a down side.
>>>>>> >>
>>>>>> >> I still think the access token model with the signed request is
>>>>>> the way I'd like to go, because again, it's a mechanism I'd be implementing
>>>>>> anyway to talk to any 'normal' resource. The fact is there is _something_
>>>>>> representing context that has to pass back and forth here, whether that is
>>>>>> an access token (which I feel like is more flexible for extensions etc), a
>>>>>> unique url, or even a cookie sent in the cookie header. So just to
>>>>>> re-iterate, I'm a +1 on this pull request, speaking as a lazy developer ;)
>>>>>> >> -steve
>>>>>> >>
>>>>>> >> On Fri, Dec 11, 2020 at 8:51 PM Fabien Imbault <
>>>>>> fabien.imbault@gmail.com> wrote:
>>>>>> >> Again speaking in my own name here.
>>>>>> >>
>>>>>> >> Dick, we know you'd prefer to have a different design, but this PR
>>>>>> shouldn't be about that.
>>>>>> >>
>>>>>> >> Back on your 3 items :
>>>>>> >>
>>>>>> >> 1) yes we could make pre-register mandatory, but we already
>>>>>> decided that wouldn't be how that would work. We have a client instance
>>>>>> that allows a more generic and flexible pattern (which BTW also allows what
>>>>>> you want)
>>>>>> >>
>>>>>> >> 2) instead of blame arguments of who's less
>>>>>> restful/HATEOAS/whatever that have the tenancy to flame conversations, I
>>>>>> suggest we speak in less abstract terms and ask ourselves what that means
>>>>>> in practice for devs. Stephen and several others (myself included) have
>>>>>> expressed that it wouldn't be harder to implement, it would even simplify
>>>>>> things quite a lot. If you disagree please send us a code sample to really
>>>>>> show that point by example, because that's really not obvious.
>>>>>> >>
>>>>>> >> 3) "If someone has the client credentials, they can impersonate
>>>>>> the client, and all bets are off." Are you seriously making this argument?
>>>>>> Because if you have a better proposal than using cryptographic keys, I'm
>>>>>> all hears. You make it look like there's a problem, while in reality we're
>>>>>> only relying on the basic assumption of all modern digital communications.
>>>>>> >>
>>>>>> >> And more importantly you never responded to the issues of how to
>>>>>> avoid the security pitfalls of what you proposed.
>>>>>> >>
>>>>>> >> Fabien
>>>>>> >>
>>>>>> >>
>>>>>> >> Le sam. 12 déc. 2020 à 00:35, Dick Hardt <dick.hardt@gmail.com> a
>>>>>> écrit :
>>>>>> >>
>>>>>> >>
>>>>>> >> On Fri, Dec 11, 2020 at 2:53 PM Stephen Moore <srmoore@gmail.com>
>>>>>> wrote:
>>>>>> >> But from the spec:
>>>>>> >> "
>>>>>> >> When sending a non-continuation request to the AS, the RC MUST
>>>>>> identify itself by including the client field of the request...
>>>>>> >> ...
>>>>>> >> key (object / string) : The public key of the RC to be used in
>>>>>> this request as described in {{request-key}}. This field is REQUIRED.
>>>>>> >> ...
>>>>>> >> "
>>>>>> >> So on the initial request, the key will be there.
>>>>>> >>
>>>>>> >> The client field can be an object or a string. If the client is
>>>>>> pre-registered, then a string could be provided instead of an object.
>>>>>> >>
>>>>>> >>
>>>>>> >> If you don't have the access token, then how do you differentiate
>>>>>> between two requests from the same web application by two different users?
>>>>>> Is the web application supposed to have different credentials for every
>>>>>> request?
>>>>>> >>
>>>>>> >> The AS returns a URI for manipulating the request. I would change
>>>>>> the spec so that each request would have a unique URI. This is the usually
>>>>>> RESTful pattern that the resource (the grant request) has an URI.
>>>>>> >>
>>>>>> >>
>>>>>> >> So in this case, the easy way out is to pass the access token to
>>>>>> the client, who then, as i stated before, treats the continue request as a
>>>>>> RS call (albeit a specialized version of the RS where the RS is the AS) OR
>>>>>> to use the unique URL,
>>>>>> >> but that seems open to a brute force attack by a malicious RC.
>>>>>> (What would be the point of that attack, I don't know, I guess if someone
>>>>>> had the client credentials but not any subjects/resources they could try to
>>>>>> intercept the grant via continue... I just don't feel right locking things
>>>>>> down to unique URLs that way.)
>>>>>> >>
>>>>>> >> If someone has the client credentials, they can impersonate the
>>>>>> client, and all bets are off.
>>>>>> >>
>>>>>> >> LOTS of RS servers return a resource specific URL -- my proposal
>>>>>> is no different.
>>>>>> >>
>>>>>> >>
>>>>>> >>
>>>>>> >> -steve
>>>>>> >>
>>>>>> >> On Fri, Dec 11, 2020 at 5:33 PM Dick Hardt <dick.hardt@gmail.com>
>>>>>> wrote:
>>>>>> >> Hi Stephen
>>>>>> >>
>>>>>> >> The client is signing the first request. The key *might* be in the
>>>>>> body. The client is signing all the subsequent requests as well. The
>>>>>> "access token" is not needed by the client to prove it is authorized as the
>>>>>> client is proving it is the same client again.
>>>>>> >>
>>>>>> >> In other words, I don't see the need for an access token, so it
>>>>>> does not need to be put in a URL or an auth header.
>>>>>> >>
>>>>>> >> If a developer really, really wants to hand context back to the
>>>>>> client for subsequent calls, they can put it in the URL or some other
>>>>>> method. Putting it in the HTTP Authorization header is confusing because it
>>>>>> is NOT an access token -- it is the context of the request.
>>>>>> >>
>>>>>> >> ᐧ
>>>>>> >>
>>>>>> >> On Fri, Dec 11, 2020 at 2:01 PM Stephen Moore <srmoore@gmail.com>
>>>>>> wrote:
>>>>>> >> Even though I've only been lightly following things, I feel the
>>>>>> need to voice my preference as a developer since I will probably someday
>>>>>> have to either write a RC or RS...
>>>>>> >>
>>>>>> >> The way I see it is the RC makes the initial request to the AS as
>>>>>> part of this request, it provides it's key in the body... (So no use of the
>>>>>> Authorization header)
>>>>>> >> At this point that request, represented by the continue URL +
>>>>>> "Access Token", from my lazy developer standpoint, is a Resource Endpoint
>>>>>> and Access Token, and the AS is acting as a specialized RS in this case.
>>>>>> >> So my client posts to whatever URL with the 'access token' in the
>>>>>> authorization header, just like acting on any other resource I have a token
>>>>>> for. YES, I get a new token value to use every call, and there is a
>>>>>> decision point of "Do I have another continue, or do I have a real token
>>>>>> for the resource..." But the mechanism is the same to me in the client.
>>>>>> >> Personally I like that, because if I have an access_token, I
>>>>>> already think "Put it in the auth header."
>>>>>> >>
>>>>>> >> So my vote would be +1 for the pull request at this time.
>>>>>> >> -steve
>>>>>> >>
>>>>>> >> On Fri, Dec 11, 2020 at 3:04 PM Dick Hardt <dick.hardt@gmail.com>
>>>>>> wrote:
>>>>>> >> inline ...
>>>>>> >>
>>>>>> >> On Fri, Dec 11, 2020 at 9:58 AM Justin Richer <jricher@mit.edu>
>>>>>> wrote:
>>>>>> >> Others had already responded to this previous thread, but I wanted
>>>>>> to add a couple points to clarify some things.
>>>>>> >>
>>>>>> >>> 3) What the client has to do with the "access token" is not the
>>>>>> same as access tokens for an RS. The client gets a new "access token" for
>>>>>> each grant request, and for each API call to the AS, and the client learns
>>>>>> it can not make any more API calls for that specific request when it does
>>>>>> not get an "access token" back. This is a completely different design
>>>>>> pattern than calling an RS API with an access token, and is a new design
>>>>>> pattern for calling APIs. This adds complexity to the client that it would
>>>>>> not normally have, and I don't think GNAP is the right place to start a new
>>>>>> design pattern.
>>>>>> >>>
>>>>>> >>
>>>>>> >> I’m not sure what you mean by these being different — the whole
>>>>>> point of the design is that the client would be doing the same thing with
>>>>>> the access token at the AS that it does with the RS by re-using the access
>>>>>> token structure. Can you please describe what the differences are, apart
>>>>>> from the rotation? Presentation of the token and signing of the message are
>>>>>> identical.
>>>>>> >>
>>>>>> >> The client is getting the "access token" from its API. It is not
>>>>>> using an "access_token" in other API calls to the AS.
>>>>>> >>
>>>>>> >>
>>>>>> >> Rotation of the access token and artifacts for ongoing
>>>>>> continuation responses is a separate issue to be discussed:
>>>>>> https://github.com/ietf-wg-gnap/gnap-core-protocol/issues/87
>>>>>> >>
>>>>>> >> And for what it’s worth, GNAP is absolutely the right place to
>>>>>> have new designs — not that this is one.
>>>>>> >>
>>>>>> >> You are proposing a new way for an API to provide context for
>>>>>> subsequent API calls. Looks out of scope to me.
>>>>>> >>
>>>>>> >>
>>>>>> >>> 4) Clients that only want claims from the AS and no access tokens
>>>>>> will be required to support an API calling mechanism they would not have to
>>>>>> support otherwise.
>>>>>> >>
>>>>>> >> Correct, but the delta between the calls a client would make with
>>>>>> and without an access token is vanishingly small. The client has to sign
>>>>>> the initial request in some fashion, and it will sign the continuation
>>>>>> request in the same exact fashion, but now include an access token in that
>>>>>> request.
>>>>>> >>
>>>>>> >> Per my other point, there is no value to me in my implementations
>>>>>> of passing context back and forth between the client and AS -- so it is
>>>>>> extra work providing no value.
>>>>>> >>
>>>>>> >> Also, any client authentication mechanism that wants to use the
>>>>>> HTTP Authentication header is precluded from using it.
>>>>>> >>
>>>>>> >>
>>>>>> >>
>>>>>> >> Clients making a request to an AS and not getting an access token
>>>>>> is a new design pattern. I think it has value and should be included, but
>>>>>> OAuth today shows us the immense value of getting access tokens for calling
>>>>>> APIs, and so we shouldn’t optimize away from that pattern.
>>>>>> >>
>>>>>> >>>
>>>>>> >>> 5) If the AS does not provide an "access token", there is no
>>>>>> mechanism for a client to delete the request, as the client is not allowed
>>>>>> to make a call without an "access token".
>>>>>> >>
>>>>>> >> More properly, if the AS does not provide a “continue” field then
>>>>>> the client can’t delete the request — and yes, that’s intentional. The AS
>>>>>> is telling this client instance that it can’t do anything else with this
>>>>>> ongoing request. If the AS wants to allow the client to manage it, it will
>>>>>> include the mechanisms to do so in the “continue” field.
>>>>>> >>
>>>>>> >> There is nuance in that intention. A related concern is that
>>>>>> deleting a request does not seem like it is a "continue" operation.
>>>>>> >>
>>>>>> >>
>>>>>> >>>
>>>>>> >>> 6) There is no standard identifier for the request. Debugging and
>>>>>> auditing are hampered by the client and AS having no standard way to
>>>>>> identifying a request. While one AS may provide a unique URL for each grant
>>>>>> request, another AS may use a persistent "access token" to identify the
>>>>>> grant request, and other ASs may issue a new "access token" on each API
>>>>>> call, providing no persistent identifier for the request.
>>>>>> >>
>>>>>> >> Debugging and auditing this kind of thing are functions of the AS.
>>>>>> How is interoperability harmed by different ASs having different methods to
>>>>>> identify their internal data elements? The client doesn’t need any
>>>>>> knowledge of the AS’s identifiers, it just needs to know the next steps for
>>>>>> continuing the negotiation.
>>>>>> >>
>>>>>> >> Debugging between the client and the AS was what I was referring
>>>>>> to. How does a client developer identify the request when communicating to
>>>>>> the AS developer. Seems complicated.
>>>>>> >>
>>>>>> >> ᐧ
>>>>>> >> --
>>>>>> >> TXAuth mailing list
>>>>>> >> TXAuth@ietf.org
>>>>>> >> https://www.ietf.org/mailman/listinfo/txauth
>>>>>> >> ᐧ
>>>>>> >> --
>>>>>> >> TXAuth mailing list
>>>>>> >> TXAuth@ietf.org
>>>>>> >> https://www.ietf.org/mailman/listinfo/txauth
>>>>>> >> --
>>>>>> >> TXAuth mailing list
>>>>>> >> TXAuth@ietf.org
>>>>>> >>
>>>>>> https://www.google.com/url?q=https://www.ietf.org/mailman/listinfo/txauth&source=gmail-imap&ust=1608345320000000&usg=AOvVaw0r39lH4qVOu0IQPJJYtSpI
>>>>>>
>>>>>> --
>>>>> TXAuth mailing list
>>>>> TXAuth@ietf.org
>>>>> https://www.ietf.org/mailman/listinfo/txauth
>>>>>
>>>>
>>>>
>>>> --
>>>> Dave Tonge
>>>> CTO
>>>> [image: Moneyhub Enterprise]
>>>> <http://www.google.com/url?q=http%3A%2F%2Fmoneyhubenterprise.com%2F&sa=D&sntz=1&usg=AFQjCNGUnR5opJv5S1uZOVg8aISwPKAv3A>
>>>> Moneyhub Financial Technology, 5th Floor, 10 Temple Back, Bristol, BS1
>>>> 6FL
>>>> t: +44 (0)117 280 5120
>>>>
>>>> Moneyhub Enterprise is a trading style of Moneyhub Financial Technology
>>>> Limited which is authorised and regulated by the Financial Conduct
>>>> Authority ("FCA"). Moneyhub Financial Technology is entered on the
>>>> Financial Services Register (FRN 809360) at *https://register.fca.org.uk/
>>>> <https://register.fca.org.uk/>*. Moneyhub Financial Technology is
>>>> registered in England & Wales, company registration number  06909772 .
>>>> Moneyhub Financial Technology Limited 2019 ©
>>>>
>>>> DISCLAIMER: This email (including any attachments) is subject to
>>>> copyright, and the information in it is confidential. Use of this email or
>>>> of any information in it other than by the addressee is unauthorised and
>>>> unlawful. Whilst reasonable efforts are made to ensure that any attachments
>>>> are virus-free, it is the recipient's sole responsibility to scan all
>>>> attachments for viruses. All calls and emails to and from this company may
>>>> be monitored and recorded for legitimate purposes relating to this
>>>> company's business. Any opinions expressed in this email (or in any
>>>> attachments) are those of the author and do not necessarily represent the
>>>> opinions of Moneyhub Financial Technology Limited or of any other group
>>>> company.
>>>>
>>>> Moneyhub Enterprise is a trading style of Moneyhub Financial Technology
>>>> Limited which is authorised and regulated by the Financial Conduct
>>>> Authority ("FCA"). Moneyhub Financial Technology is entered on the
>>>> Financial Services Register (FRN 809360) at
>>>> https://register.fca.org.uk/. Moneyhub Financial Technology is
>>>> registered in England & Wales, company registration number 06909772.
>>>> Moneyhub Financial Technology Limited 2020 © Moneyhub Enterprise, Regus
>>>> Building, Temple Quay, 1 Friary, Bristol, BS1 6EA.
>>>>
>>>> DISCLAIMER: This email (including any attachments) is subject to
>>>> copyright, and the information in it is confidential. Use of this email or
>>>> of any information in it other than by the addressee is unauthorised and
>>>> unlawful. Whilst reasonable efforts are made to ensure that any attachments
>>>> are virus-free, it is the recipient's sole responsibility to scan all
>>>> attachments for viruses. All calls and emails to and from this company may
>>>> be monitored and recorded for legitimate purposes relating to this
>>>> company's business. Any opinions expressed in this email (or in any
>>>> attachments) are those of the author and do not necessarily represent the
>>>> opinions of Moneyhub Financial Technology Limited or of any other group
>>>> company.
>>>>
>>>>
>>
>> --
>> Dave Tonge
>> CTO
>> [image: Moneyhub Enterprise]
>> <http://www.google.com/url?q=http%3A%2F%2Fmoneyhubenterprise.com%2F&sa=D&sntz=1&usg=AFQjCNGUnR5opJv5S1uZOVg8aISwPKAv3A>
>> Moneyhub Financial Technology, 5th Floor, 10 Temple Back, Bristol, BS1 6FL
>> t: +44 (0)117 280 5120
>>
>> Moneyhub Enterprise is a trading style of Moneyhub Financial Technology
>> Limited which is authorised and regulated by the Financial Conduct
>> Authority ("FCA"). Moneyhub Financial Technology is entered on the
>> Financial Services Register (FRN 809360) at *https://register.fca.org.uk/
>> <https://register.fca.org.uk/>*. Moneyhub Financial Technology is
>> registered in England & Wales, company registration number  06909772 .
>> Moneyhub Financial Technology Limited 2019 ©
>>
>> DISCLAIMER: This email (including any attachments) is subject to
>> copyright, and the information in it is confidential. Use of this email or
>> of any information in it other than by the addressee is unauthorised and
>> unlawful. Whilst reasonable efforts are made to ensure that any attachments
>> are virus-free, it is the recipient's sole responsibility to scan all
>> attachments for viruses. All calls and emails to and from this company may
>> be monitored and recorded for legitimate purposes relating to this
>> company's business. Any opinions expressed in this email (or in any
>> attachments) are those of the author and do not necessarily represent the
>> opinions of Moneyhub Financial Technology Limited or of any other group
>> company.
>>
>> Moneyhub Enterprise is a trading style of Moneyhub Financial Technology
>> Limited which is authorised and regulated by the Financial Conduct
>> Authority ("FCA"). Moneyhub Financial Technology is entered on the
>> Financial Services Register (FRN 809360) at https://register.fca.org.uk/.
>> Moneyhub Financial Technology is registered in England & Wales, company
>> registration number 06909772. Moneyhub Financial Technology Limited 2020 ©
>> Moneyhub Enterprise, Regus Building, Temple Quay, 1 Friary, Bristol, BS1
>> 6EA.
>>
>> DISCLAIMER: This email (including any attachments) is subject to
>> copyright, and the information in it is confidential. Use of this email or
>> of any information in it other than by the addressee is unauthorised and
>> unlawful. Whilst reasonable efforts are made to ensure that any attachments
>> are virus-free, it is the recipient's sole responsibility to scan all
>> attachments for viruses. All calls and emails to and from this company may
>> be monitored and recorded for legitimate purposes relating to this
>> company's business. Any opinions expressed in this email (or in any
>> attachments) are those of the author and do not necessarily represent the
>> opinions of Moneyhub Financial Technology Limited or of any other group
>> company.
>>
>>

-- 
Dave Tonge
CTO
[image: Moneyhub Enterprise]
<http://www.google.com/url?q=http%3A%2F%2Fmoneyhubenterprise.com%2F&sa=D&sntz=1&usg=AFQjCNGUnR5opJv5S1uZOVg8aISwPKAv3A>
Moneyhub Financial Technology, 5th Floor, 10 Temple Back, Bristol, BS1 6FL
t: +44 (0)117 280 5120

Moneyhub Enterprise is a trading style of Moneyhub Financial Technology
Limited which is authorised and regulated by the Financial Conduct
Authority ("FCA"). Moneyhub Financial Technology is entered on the
Financial Services Register (FRN 809360) at *https://register.fca.org.uk/
<https://register.fca.org.uk/>*. Moneyhub Financial Technology is
registered in England & Wales, company registration number  06909772 .
Moneyhub Financial Technology Limited 2019 ©

DISCLAIMER: This email (including any attachments) is subject to copyright,
and the information in it is confidential. Use of this email or of any
information in it other than by the addressee is unauthorised and unlawful.
Whilst reasonable efforts are made to ensure that any attachments are
virus-free, it is the recipient's sole responsibility to scan all
attachments for viruses. All calls and emails to and from this company may
be monitored and recorded for legitimate purposes relating to this
company's business. Any opinions expressed in this email (or in any
attachments) are those of the author and do not necessarily represent the
opinions of Moneyhub Financial Technology Limited or of any other group
company.

-- 


Moneyhub Enterprise is a trading style of Moneyhub Financial Technology 
Limited which is authorised and regulated by the Financial Conduct 
Authority ("FCA"). Moneyhub Financial Technology is entered on the 
Financial Services Register (FRN 809360) at https://register.fca.org.uk/ 
<https://register.fca.org.uk/>. Moneyhub Financial Technology is registered 
in England & Wales, company registration number 06909772. Moneyhub 
Financial Technology Limited 2020 © Moneyhub Enterprise, Regus Building, 
Temple Quay, 1 Friary, Bristol, BS1 6EA. 

DISCLAIMER: This email 
(including any attachments) is subject to copyright, and the information in 
it is confidential. Use of this email or of any information in it other 
than by the addressee is unauthorised and unlawful. Whilst reasonable 
efforts are made to ensure that any attachments are virus-free, it is the 
recipient's sole responsibility to scan all attachments for viruses. All 
calls and emails to and from this company may be monitored and recorded for 
legitimate purposes relating to this company's business. Any opinions 
expressed in this email (or in any attachments) are those of the author and 
do not necessarily represent the opinions of Moneyhub Financial Technology 
Limited or of any other group company.