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Can OpenID solve the mobile web application login problem? February 25, 2008

Posted by James Webster in : web, mobile , add a comment

LinkedIn have announced LinkedIn Mobile (via TechMeme) available at http://m.linkedin.com. The ‘m.’ prefix has definitely become the defacto way to access mobile-specific versions of web applications; so much for the .mobi TLD then which is after all a pain to enter onto a phone keypad without the benefit of T9.

Anyway, having a mobile version of LinkedIn and Facebook and which-social-network-is-hot-this-month is all good but now I have the challenge of having to enter my username and password for the mobile version as well. See, since I use Johannes la Poutré’s Password Composer bookmarklet to generate a unique password based on a hash of the website’s domain and a strong password that never leaves my browser (see Jon Udell’s excellent screencast from 2005 on Simple Single Sign-On to understand more) I don’t really know what my password for LinkedIn/Facebook/etc is, at least not off the top of my head.

It has struck me that OpenID could provide a solution here. If my carrier offered an OpenID provider tied to my phone number I could authenticate to OpenID-compatible websites using my phone in hopefully a reasonably transparent fashion, once I had maybe used the main web interface of LinkedIn (or Facebook, etc, etc) to approve my OpenID on my mobile carrier’s provider.

OpenID has seen a growth in support from big players in the industry, with Google, VeriSign, IBM, Microsoft and Yahoo! all joining recently as corporate board members of the OpenID Foundation. Some of them have OpenID-access enabled to their web applications or OpenID-providers available as beta releases. Major mobile carriers are conspicuously absent however. To me, it seems like they missing a major opportunity to innovate.

Oh, and here’s a link to my LinkedIn profile :-).

Markets and Excel and VBA, oh my. February 20, 2008

Posted by James Webster in : finance, development , 3 comments

Spend any time at a fund manager or investment bank and you will quickly realize how much of life is lived inside a spreadsheet. And when I say spreadsheets I mean Excel.

A great deal of those Excel spreadsheets also have a great deal of VBA. I have heard many of my professional developer colleagues pooh pooh VBA but the fact remains that there is a hell of a lot of VBA code written in Excel to implement complex financial models and derivatives pricing (albeit in the latter case, interfacing via COM or XLL add-ins with analytics libraries written in C++). I have spent a significant amount of time working and interfacing with VB/VBA code for this purpose in my day job.

The big question is, what will happen to VBA? It has already failed to make the cut for the latest version of Microsoft Office for Mac. This article over at The Register did claim that VBA would be removed from Office when the next version after Office 2007 was released, around 2009, however Microsoft has since said that is not the case and a retraction has been posted. That said, I expect that Microsoft would very much like to deprecate the VBA runtime environment in Office due to the additional support burden on top of .Net integration with Office.

However the existing base of users who consider themselves Office developers are unlikely to simply adopt Visual Studio Tools for Office with its additional ‘burdens’ of compilation, object orientation and static typing… although having said that I do want to avoid igniting a religious war! Porting from VBA to .Net/VSTO is also a non-trivial process.

So a new product like Resolver One from Resolver Systems is quite interesting to me. It is basically a spreadsheet application that is highly programmable in Python (via, I believe, IronPython) supporting integration with .Net and therefore everything that .Net can integrate with. Resolver System’s Giles Thomas describes it better than I in the YouTube video below.

Having had a quick look at the Resolver Systems forums however I believe they may have an upward battle in getting their product broadly adopted (which they may not need to be a commercial success at any rate). Excel is absolutely entrenched and for Resolver One to completely replace Excel in many environments they will need parity all the way down to the look & feel and user interaction level. One suggestion provided by another user was for Resolver One to operate as an Excel add-in; quite how that would work I am not sure, maybe they would employ something like Managed XLL to dynamically create Excel functions that bind to the Python methods in the Resolver view of a workbook.

However if Resolver One could interpret the VBA code in an existing Excel spreadsheet, either by dynamically or statically converting it into Python or IL or whatever it runs under the hood, they could have a very interesting product on their hands. It would be very appealing to the IT shops of investment banks that have a pool of Excel spreadsheets for which they wish to scale calculation out across their grid (assuming they haven’t gone down the Excel Calculation Services on Computer Cluster Server route for whatever reason). Effectively implementing their own VBA runtime on top of .Net may also ease porting of VBA to .Net languages by allowing the VBA code to be incrementally ported.

A few other thoughts about Resolver One:

And a few other interesting links about Excel:

More Investment Banking knowledge for IT Professionals February 18, 2008

Posted by James Webster in : finance , 4 comments

A while ago I put together a presentation describing at a very high-level the primary reasons for the existence of financial/capital markets, who participates in them, and what the major financial markets are. I have delivered this presentation at a couple of ThoughtWorks Away Days now and people have told me that it was a great high-level introduction to the domain. I have wanted to put it online for the benefit of anyone else looking for a quick dose of background information and I have finally gotten around to it. Be aware that the recording is from 2006 and some other ways that I simplify and explain certain concepts is probably not 100% accurate and I’d probably describe things a little differently these days.

With that caveat out of the way, please enjoy “The Why, Who, What and Where of Financial Markets”. The full presentation runs for about 45 minutes but you can also download an iPod-compatible version from blip.tv ;

If you are interested in further background and understanding here is my recommended reading list (disclosure: the Amazon links are to my personal affiliate account);

  1. Business Knowledge for IT in Investment Banking by Essvale Corporation Amazon US Amazon UK: if you need a very quick introduction then this might be worth a shot. I have not read it from cover to cover but it looks to provide a bit of background into the major networks and information services, which might be particularly useful for an IT practitioner.
  2. An Introduction to Global Financial Markets by Stephen Valdez Amazon US Amazon UK: I started with this one myself many years ago. It is clear and provides some interesting context on the history of banking. Definitely global in focus and recent editions have included specific coverage of the financial market impact of 9/11, the .com crash, etc. I wonder if the next edition will cover the sub-prime crisis and credit crunch?
  3. Trading and Exchanges; Market Microstructure for Practitioners by Professor Larry Harris: Amazon US Amazon UK: A very deep but remarkably clear analysis of the inner workings of markets. Looks at the economics and structure of markets from both a theoretical and practical perspective and has plenty of humour throughout.
  4. Traders, Guns & Money: Knowns and unknowns in the dazzling world of derivatives by Satyajit Das Amazon US Amazon UK: a controversial insider’s look at some of the shadier goings on in the field of exotic derivatives for all asset classes. Despite the book dripping with cynicism (whether it is misplaced or not is left to you to decide!) it does put various boom and bust stories surrounding derivatives into context. It also describes the exotic credit derivatives; CDOs, CDSs etc, very well… although whether these derivatives will continue to exist for much longer in their current form is currently under question!

Wikipedia’s page on financial markets is also a great entry point to a range of other articles.