Networking in SOA Environments - Definitions

There is a need to come to some kind of agreement on definitions related to networking in SOA environments. Here is my attempt and I am soliciting input from others to help refine. I appreciate your comments. 

One fundamental difference that needs to be clarified is the difference between the "Networking of Services" used to build SOA and "Network Service Delivery Environments" used to build Networks (which may or not be built on SOA principles).

Service-Oriented Architecture (SOA)

I won’t go into the definition or the principles of SOA here. There are many definitions out there.  For a very good reference on this subject I would refer to Thomas Erl's books for definitions and principles of SOA - www.soabooks.com .

Although SOA comes from a heritage of distributed computing, many authors and visionaries of SOA didn’t consider network infrastructure in their books. Here is my attempt to clarify things. In the following article, I use web services and services interchangeably.

Enterprise SOA vs. B2B SOA

Enterprise SOA is the first bastion for the adoption of SOA since it was seen as a way of solving integration problems and breaking down silos within the Enterprise. B2B SOA is focused on exposing services beyond the enterprise (outside of the firewall) so they can be orchestrated or choreographed into services or applications processes between Enterprises that are distributed. B2B then requires some kind of network to carry these distributed services. While Enterprises can have distributed office locations, Enterprise SOA generally assumes that services are located behind a firewall and B2B are generally assumes services are exposed beyond the firewall. 

Application-Oriented Networking (AON)

Application-Oriented Networking was coined as an acronym actually before SOA was commonly used. Since services are actually smaller compose-able units than an application, AON may or may not include applications that are built upon services. AON is focused on the networking of applications and associated acceleration, performance, etc of applications. Since AON preceded SOA and since it may or may not be made up of services - this definition is not clear and therefore there is a need to introduce a new acronym.  I propose Service-Oriented SOA Networking (SOAN) to further clarify that services or applications  processes that are composed of services and the network is carrying services and not just applications.  An SON is focused on the networking and management of processes and services and is less about applications.  While this may sound trivial the management of services (which are re-useable, compose-able) is far more demanding than managing applications over a network.  There are presently a number of companies that provide AON solutions but have no comprehension of what SOA is all about.  I believe that applications will give way to "processes" and "services" and the term "applications" will fade in use. 

XML Networking

XML networking to me means the simple exchange of XML (RMI or document based) over a network and is focused on the lower level of the stack and may or may not be carrying services to be used in a SOA environment or between SOA environments.  Therefore we need to further qualify.

Web Services Networking

Web Services Networking is the exchange of services. These services can be used simply to exchange information and may or may not be used for orchestrating, choreographing,  or communicating services between SOA environments.  A bunch of web services are not equal to SOA, so further qualification is needed.

Service-Oriented Networking (SON)

Service-Oriented Networking is the focused on the networking and management of services over networks within or between SOA environments.  I tend to think of SON as networking of services between homogeneous SOA environments for orchestrating or choreographing; where no brokering or mediation of services are required between these SOA environments.  AON cannot in my opinion be considered to encompass SON because they are radically different concepts.  If all applications were built on web services then we could consider that AON encompasses the concept of SON.

Service-Oriented Networking is being used by the IT world to describe networking of "distributed web services".  The term Service-Oriented Network is also being used by the Telecom World to describe delivery of "Network Services" ie. Voice, Video, IPTV network based applications.  These network services and the Service Delivery Platform may or may not be SOA based.  There is a lot of ambiguity around this term SON since it is not clear whether Services are "Web Services" or "Network Services" and whether these services are SOA-based or not.  At the moment, I see the Telecom side of the house using this term more than the IT side of the house.  Should we stick with this term to mean two different things?   Actually I was mistaken there is another version of SON.  Cisco actually uses Service-Oriented Networking (within SONA) in the context of Network Services where a service is a generic functionality that may cross a variety of networks: security, identity, etc.  These services may or may not be based on web services and definitely not the same thing as a service in the context of "Service Oriented Architecture".

SOA Networking (SOAN)

SOA Networking means the networking of SOA environments which may or may not be homogeneous. If they are not homogeneous then there are requirements to mediate between these environments through some kind of a gateway.  SOAN includes and can be used interchangeable with Service-Oriented Networking, but I tend to think that SOAN introduces the concept of interoperability between heterogeneous SOA environments where there is some kind of brokering or mediation required. 
SOA Networking is based on XML, SOAP and Web Services but doesn't necessarily encompass XML Networking and Web Services Networking since it is possible to have the exchange of XML documents, or the exchange of web services without being Service-Oriented. (Although the implementation of some SOA Appliances like Layer 7 include all capabilities in one box and software enable for various applications).

This is a draft, and I will evolve these definitions and try to work in other related terms and company specific terminology such as SONA.

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Gary E. Smith
SOA Network Architect