Enter the Internet Service Bus
On April 24th Microsoft released the BizTalk Services CTP, taking the idea of an Enterprise Service Bus (ESB) as as a means of discovering, connecting and federating services a step further and elevating it to the Internet Service Bus (ISB).
Today building distributed applications requires a lot of infrastructure efforts. ESBs are used to provide infrastructure services, such as identity and relaying services, within a single company or enterprise. Soon things get out of hand, when your applications or systems span more than one enterprise or are provided publicly on the internet. The infrastructure investments will start to grow, leaving less and less place for the original business. Clemens Vasters, Senior Program Manager at the Microsoft Connected Systems Division, explains the need for infrastructure services and introduces the BizTalk Services CTP as the first Internet Service Bus addressing these needs on an internet scale:
Two aspects that make the idea of a "service bus" generally very attractive are that the service bus enables identity federation and connectivity federation. This idea gets far more interesting and more broadly applicable when we remove the "Enterprise" constraint from ESB it and put "Internet" into its place, thus elevating it to an "Internet Services Bus", or ISB. If we look at the most popular Internet-dependent applications outside of the browser these days, like the many Instant Messaging apps, BitTorrent, Limewire, VoIP, Orb/Slingbox, Skype, Halo, Project Gotham Racing, and others, many of them depend on one or two key services must be provided for each of them: Identity Federation (or, in absence of that, a central identity service) and some sort of message relay in order to connect up two or more application instances that each sit behind firewalls - and at the very least some stable, shared rendezvous point or directory to seed P2P connections. The question "how does [MSN] Messenger work?" has, from an high-level architecture perspective a simple answer: The Messenger "switchboard" acts as a message relay.
John Shewchuk gives an overview of the BizTalk Services in the Connected Systems blog and Dennis Pilarinos shows how to get started with the CTP. Currently the following services are online or planned:
- BizTalk Identity Services - technologies to help developers manage application identity and access control requirements
- BizTalk Connectivity Services - technologies to help developers securely expose a service from behind a firewall or NAT
- BizTalk ServiceBus Services - technologies to help create loosely coupled applications with eventing... - Coming soon!
- BizTalk Workflow Services - Coming soon!
eWeek has published two articles on the subject. The first article discussed Microsoft's vision for SOA and the BizTalk services in general, and the second features several statements about Microsoft's latest coup in the SOA field from different analysts, consultants and developers.
Stephen Forte, co-founder and CTO of Corzen, Inc, a company specializing in custom data mining and specific collection of data from the internet via spidering, writes about the business case for and the business value of BizTalk Services. He concludes that
BizTalk services and ultimately all of the Software plus Services (including other vendors, not just Microsoft) will change the way we do business in 5-10 years. Imagine if we had to run a switchboard to run our phones in the office? So an oil company or a bank would have to develop the technical expertise to run the phones. This infrastructure is solved by the phone company (and now VoIP!) In the future, businesses will only have to focus on their core businesses and most software will run locally with services up in the cloud, drastically reducing the investment in core IT infrastructure internally. It’s a brave new world out there.
Microsoft's vision of an ESB as a set of products, technologies, and techniques rather than a single product fits well into their general SOA strategy. It will be interesting to see, how the BizTalk Services will be adopted by both, the community and the industry.