Thursday, May 10, 2007

SOA & IMS: Same Fight?

Here is an excellent article about the difficulties for the Service Oriented Architecture (SOA) to be adopted in the IT community: Finding the Real Barrier to SOA Adoption.

I defend the idea that SIP and IMS can integrate with and extend SOA by adding user orientation to an approach which is service centric. I already started to describe some architectural aspects of IMS, and the possibility to implement service logic as a distributed set of individual services reusable by others.

This is therefore not a surprise that I can identify within the telecom industry the same types of problem with regards to IMS and SIP, that the author of this article does with SOA and the IT industry.

He states that IT organizations are the first barrier to SOA adoption. I also think that existing telco organizations play such a role for IMS.

SOA permits to solve some complexity issues that IT organizations want to maintain, for the sake of keeping their job. I would liken this to the subdued but real ongoing fight between some of the telco vendors, who want to maintain complexity in the IMS, and IT suppliers, who can help make IMS much simpler for service developers.

SOA forces to think differently, in terms of reusability, architecture, and distribution. This is the same for IMS, which could support a new service architecture, much more distributed and powerful than the legacy ones.

The reference to silos is explicitly linking to the application silos we know in our networks, and that start to be implemented as well on IMS.

The fear of the unknown is also a very common problem in our industry, as people just want to work on topics they have already been addressing for years. Just look at how current SCIM/Service Broker standardization is just a way to keep on working on the old IN service interaction management problem and not to think of what could be beyond voice.

I would add an IMS-specific problem related to SOA: many people in the telecom industry that defend SOA concepts do not want to accept the idea that IMS is more than just another telco network, and that it supports SOA-related concepts as well.

Christophe

7 comments:

Anonymous said...

I agree that IMS integate SOA.
I do not understand though how you can differentiate between SIp and IMS.
To my knowledge there is no IMS without SIP!

Christophe Gourraud said...

You are right, there is no IMS without SIP. However, you can have SIP without IMS! More especially in the Internet. This is why I make the distinction: a SOA making use of SIP does not have to be limited to IMS.
Christophe

siva said...

I have a question about SOA and IMS. My question how IMS integrate the SOA? Does that use parlayX webservice for existing SIP services and involved in SOA?

I don't know whether it is simple question.But I don't understand what is the same type of problem avilable in SIP/IMS and SOA?

Christophe Gourraud said...

Hi Siva,

You may find some input in others of my post, like this one:
http://theimslantern.blogspot.com/2007/06/ims-application-server-in-context.html

My claim is that you should not see IMS purely as a communication network and SIP purely as a session control protocol. They can support this but they can do much more.

SIP can be used for various service control purposes and an interesting feature of SIP and IMS is the ability to use user identities as addresses in SIP requests. This means that a SIP request that can virtually serve any service purpose addressed to a user can reach the user itself, but also devices associated to the user (e.g. various types of terminals or user-associated servers) and applications associated to the user (in SIP ASs or in devices).

This complements a SOA architecture usually using web services with a user oriented dimension using SIP and the protocols it combines with.

Christophe

Anonymous said...

Let us assume IMS is more than just another telco network: Why do we need yet another network?

Christophe Gourraud said...

Well, for instance...

For fixed operators to get rid of their aging, heterogeneous and expensive circuit-switched network and replace it with an all-IP one that can provide the same level of services (including regulated ones).

To support fixed mobile convergence, making that one day the slicing of a human being into a fixed subscriber and a mobile subscriber will be history.

To mix communication, content, data and applications together.

For operators to rapidly and cost effectively deploy innovative services, and invent innovative ways to relate to 3rd party service providers in the Internet or elsewhere.

For establishing SIP as the interoperable standard for communication within and across telecommunications networks, the Internet and enterprises, thus getting rid of the communication islands created by the telecommunications industry and the big Internet names.

As you seem to be very suspicious about the IMS, just think about the following point: IMS is a specific instance of a SIP network that can interoperate with other SIP networks, and SIP is a protocol that was created by the Internet community to fill a hole in the suite of Internet protocols existing at the time.

Christophe

Roxanne said...

Quite useful info, thank you for the article.