Do you really need SAP PI or indeed any ESB when implementing web services?

[Former Member]

Hi,

We are currently running ECC 5.0 and are working on developing some web services which will be hosted on the SAP system.

A question arose whether we should look to implement a ESB, I'm wondering what benefit a ESB has when using web services.

What types of scenarios/usage would warrant investing in ESB?

Would appreciate any comments the community may have around using or indeed deciding not to use a ESB when running web services in SAP, thanks.

[rajasekhar_reddy14]

Hi,

You can use any ESB , but PI offering easy integration with SAP Systems compare to other middlewares.

If your system supports Webservice cals,no mapping and routing required,then no need to use ESB,using WebService cals we can easily integrate systems.

Regards,

Raj

[Former Member]

Hi,

Thanks to all so far, good debate!

The point we are at is creating internal web services which don't require any mapping or various routings so just point to point. From the feedback I have had so far not using an ESB for this is acceptable.

Ongoing though if things take off with external connections with more complex business scenarios a ESB makes sense.

One additional clarification point, I'm assuming if you have a few standard point to point web services in place and then bought in a ESB it would be easy to move your web services into the ESB?

Thanks.

[Former Member]

Hi Spencer,

It would be easy, you won't need to move your webservices anywhere, you would just move the complex message processing into the ESB. So the consumer/provider would hit the ESB endpoint first & the message then gets mapped (or triggers a ccBPM for example) before reaching your current endpoint and then follow the same route through the ESB back.

You would just re-use your current webservice WSDL for further implementation in the ESB.

Regards, Trevor

[Former Member]

Hi Spencer,

Can you please see jins reply in this thread:

Regards,

---Satish

[Former Member]

Satish,

Thanks for the response, the thread you pointed me to is a bit of an old thread though!

If web services being used don't need any data mapping/transformation is the ESB layer beit SAP PI or any other tool really necessary? What does ESB bring to the table?

Thanks.

[Former Member]

HI Spencer,

Some of them you can see in this blog:

/people/swarup.sawant/blog/2008/02/18/a-perception-150-is-pixi-as-an-enterprise-service-bus-esb

Also there are few things which are added in PI 7.1 like the introduction of the Enterprise Service Repositroy (ESR), adoption of webservices and standards like WS-RM, distribution of adapter engines and local point-to-point integration scenarios.

http://www.sdn.sap.com/irj/sdn/webservices#section2

http://rsol08.wordpress.com/2008/05/16/esb-and-sap/

Regards,

---Satish

[Former Member]

Hi Spencer,

All an ESB really does is add a great deal of flexibility for a customer...

It all depends on where the customer is headed & future planning, if the customer is quite happy with point-to-point webservice functionality for now, it may just be okay for now. What if the conditions suddenly change in the space that the customer plays in. A point-to-point connection significantly reduces the customer's ability to adapt to changes. If the customer is unable to adapt quickly & the competition is able to then business growth possibilities are reduced...

What if you suddenly need some complex Business Process Management? It's going to take quite a while to code this with a point -to-point connection...An ESB also adds a much stronger security layer if that's a concern.

So, you're right, an ESB isn't necessary, if you want to be chasing tails while other's are growing at light speed. Another example, what if there are 2 customers that are banks (one with point-to-point connections & one with an ESB) & the actuaries at both the banks devise a product offering that will make the banks millions if they get the product to the market very quickly. Who will get there first? The one with the ESB will get there first every time. When you start thing aboutWebservice Orchestration and Composite Applications then you begin to understand the power that an ESB adds to an organisation.

Regards, Trevor