I am in Budapest today and I am just done with my Indigo talk (you can find the slides at http://codezone.info under “Talks”), having done it for the 6th time on this tour throughout Europe. After the events Den Haag, Oslo, Copenhagen, Helsinki and Geneva, I still find Indigo a very difficult topic to talk about on this tour. It’s not about technology or because my talk doesn’t work: It’s about whether people think it’s relevant to their work.

The true challenge is to explain to the developers we meet that Indigo is going to be very important for them down the road. I find that when I talk to developers on this tour or look at their evaluation forms that very many of them apparently still write fairly compact (to avoid the word monolithic) ASP.NET applications or Windows Forms applications that use a conservative client/server approach. All presentation and logic resides in one tier and the only remote component worth mentioning is the database. That means that the majority of the folks sitting in my talks hasn’t even touched one of the existing distributed technology stacks that Indigo is set to replace.

The difficulty presenting Indigo on this tour – alongside sexy stuff like declarative UI programming with spinning Windows and Videos with alpha-blending in Avalon and googlefast cross-media searches across all of your local storage media as in WinFS – is that Indigo is about things that are hidden inside applications and do not surface to the user. Stuff that drives server-applications is sometimes hard to understand without knowing the architectural background and the motivations. (Sidenote: A while ago I heard a rumor from a usually trustworthy source that the spinning balls in the COM+ Explorer exist because COM+ was horribly hard to demo as well and the spinning balls provided a good way of visualizing that stuff was happening.)

The ideal talk for an unsuspecting audience with little knowledge in distributed systems would have to sell the whole idea of distributed systems to boot, the experiences and errors made, the reasons for why Web services are a good thing, the problems creating the motivation for and the principles of service oriented architectures, a set of some tangible application examples and use cases along with the solutions that Indigo provides; all of that in the same talk and within 75 minutes. And that in a way that developers get to see code and demos, too. That sort of talk would span about 20 years of distributed computing history. I am not sure this fits in 75 minutes. Therefore I think I will have to be happy with only a fraction of the audience being interested and/or willing to appreciate the things that I am talking about here. 

Very many folks think that the topics I am talking about are only relevant to “big apps” and have a hard time seeing the benefits of something like Indigo – much in the same way as it is with Enterprise Services or Web Services.

If you believe Don Box, who said at PDC that Indigo will ship at some point between Whidbey and Longhorn, and think about the implications of that, Indigo is in fact relevant to everyone writing applications that expose functionality to other applications in some way – now or at least quite soon. The first ship vehicle for Indigo will be, if Don’s statement holds water in its consequences, some service pack or upgrade pack for Windows Server 2003 and Windows XP. That means nothing less than the entire application infrastructure of Windows Server 2003 is getting a major upgrade probably in a year or so from now.

If you are writing applications using ASMX, Remoting or Enterprise Services today, the impact of Indigo’s arrival can be immediate if you want to make it so. If you code your applications cleverly today (following guidelines explained by Joe Long here or in my talk) and don’t play too many tricks on the infrastructure – for instance by using the Remoting extensibility points – you should have a fairly smooth upgrade path to Indigo. The goal is that upgrading code will be simple and mechanical in most cases.