One of the important building blocks in helping IBM construct its Systems Oriented Architecture (SOA) is an Enterprise Service Bus (ESB). Over the past year or so, IBM has been delivering products that would help constitute an ESB, but delivery of all of the necessary pieces will not come until late this year. A key figure in helping Big Blue put those pieces in place is Bob Sutor, IBM's director of Web Services Technology for IBM's WebSphere. In his current role, Sutor is in charge of overseeing the future direction of the WebSphere Application Server and WebSphere Studio product lines. Sutor sat down with Ed Scannell to discuss IBM's on-going efforts to create an ESB.
Q: It seems that IBM has been downplaying an EnterpriseService Bus as part of its longer-term Systems Oriented Architecture plans?
Sutor: It will evolve. But to pretend it is something new, something we have to wait for standards to come along is wrong. We have some of the pieces today that customers can use to start to build with. The way I look at it, an ESB is not something you buy off the shelf because everyone will have a slightly different one. You could start with just two applications servers. Is that an ESB? I could argue that it is. You have the connectivity, ability to program the end points and do data transformation. You could add MQ that adds reliability and asynchronous communications. You could add brokers, which adds intelligence to the backbone so you can make better choices about where to route things.
Q: When might IBM deliver a full ESB?
Sutor: The plan now is to deliver something in the second half of the year.
Q: When might you complete an ESB?
Sutor: Well, you can draw pretty pictures of ESBs like a nice big pipe with all these things plugging into it. But the actual ESB is going to be a combination of several things and these things will vary by customer. Probably no two users will have exactly the same ESB. A list of such things could include an enterprise messaging backbone like MQ. You could include the Internet, i.e. as a transport, you could include brokers of different capabilities --big brokers that can transform everything to everything else, or the smaller ones that are more specialized for certain protocols. But with app servers, once they plug into the bus, in some sense it becomes part of the bus.
Q: What is the level of interest among users for ESBs?
Sutor: We talk to a lot of financial services companies and when we bring this up they say, "Well, we are building this anyway, so don't tell us this is something new." Think of two banks that merge -- they have all these applications. Merrill Lynch (& Co. Inc.), for instance, has 23,000 mainframe applications. Two banks merge and they each have their own infrastructures for how these things could be used. They somehow have to bridge these backbones, but they also want to eliminate redundancies. How do they do that? You start deciding, these are the standardized interfaces I will use for certain types of services, and then you start combining things and then have them all start pointing to the same one. Once that happens, I can start taking some off line.
Q: Are ESBs still an integral part of achieving your longer term SOA goals? Has it been growing in importance or decreasing?
Sutor: It was always there. Six months ago when we talked about SOAs, we talked much more about Web services, and therefore people thought of (ESBs) much more in terms of the Internet for connectivity. But now that we are really talking about SOAs and its application for the enterprise, like bridging the enterprise across the Internet it has the ring of something more important. It was always there but we are now calling it out more.
Q: Are you considering delivering multiple ESBs?
Sutor: Remember that a particular ESB could be what you happen to have installed. You could have an ESB in one company and another one in another company, and then merge these companies and bridge them into a great enterprise services bus. An ESB changes just by the nature of what the messaging backbone is and by what plugs into it.
Q: Will there be a dedicated engine in the mix for managing business processes that can plug into the bus, as well as something that coordinates Web services across the breadth of it?
Sutor: There are things you can do right now, with WebSphere Business Integration monitor for instance, that you can plug in. In fact there is a modeler that fits in as well. That is the stuff we bought from Holosofx. The modeler lets you draw the flow charts, set up conditions, and simulate things (that) might happen. The monitor can pick up real-time information about how things are moving through the business process and give you feedback.
Q: Can applications on the bus be written to messaging APIs? And will they be event driven?
Sutor: You can do both. There are messaging APIs you plug into MQ and those are straightforward things. When you talk about events, people usually think about pub-sub (publish and subscribe), and that is supported in MQ and our brokers. There are three things you want to think about in that space: One is the straight messaging use, the event side of it, and then the SOA use of it where at that point the bus tends to recede a little bit.
Q: So there will be something delivered by year's end?
Sutor: That is the plan right now. But we have only talked about enterprise connectivity. Think about connecting with wireless devices, because there you are certainly crossing other protocols. We are getting to the point now where, with JSR 172, it allows these mobile devices to actually be Web services. So you can imagine a device in a truck somewhere that is a Web service that can be queried. Part of your messaging might be over your MQ backbone, then you are going to have to jump wirelessly to access that service. The magic of bridging the bus to the wireless aspects and back is all tied up in the bus. That is why we are saying you have to have that flexibility, you must be able to deal with the existing stuff people have, the very different flavors of protocols like the On Star types of things, but also the Blackberry's. It is the bus and the increasing standardization that will make a lot of the magic happen that makes it a lot easier to connect things together.