RE: [soa-rm] David Linthicum Says: "ESB versus Fabric.Stop It!"

["Vikas Deolaliker" <vikas@sonoasystems.com>]

All of these facets of the RM can be built upon the layered approach as the
networking world has demonstrated. For example, policy can be implemented at
policy enforcement point (PEPs). All of these facets at an abstract level
need a mechanism for state transfer and mechanism for state coherence i.e.
synching local state with global state. Those mechanisms are easier to build
in a layered approach. 

But before we do that, we need to agree if layered approach is the right
approach.

Vikas


-----Original Message-----
From: Francis McCabe [mailto:fgm@fla.fujitsu.com] 
Sent: Tuesday, May 24, 2005 10:11 AM
To: vikas@sonoasystems.com
Cc: 'Michael Stiefel'; 'Chiusano Joseph'; soa-rm@lists.oasis-open.org
Subject: Re: [soa-rm] David Linthicum Says: "ESB versus Fabric.Stop It!"

And what about application semantics, policy application, service  
management, security services, service intermediaries, etc. etc. etc.?

On May 24, 2005, at 10:01 AM, Vikas Deolaliker wrote:

>
> Frank,
>
> Messages are abstract its binding to a communication model  
> (synchronous vs
> asynchronous), format (SOAP vs. plan XML) or invocation model (SOAP  
> vs REST)
> is architecture specific.
>
> About the arbitrariness of the layers. I beg to differ. The lowest  
> layer is
> deals with transport endpoints while the layers above successively  
> deal with
> higher abstraction of transport endpoints. For example Layer 2  
> deals with
> service endpoint and Layer 3 with session endpoint and Layer 4 with  
> process
> endpoint. This is a clean partition.
>
> A reference model should drive multiple architectures. The layered  
> approach
> does exactly that.
>
>
> Vikas
>
>
>
> -----Original Message-----
> From: Francis McCabe [mailto:fgm@fla.fujitsu.com]
> Sent: Tuesday, May 24, 2005 8:46 AM
> To: Michael Stiefel
> Cc: vikas@sonoasystems.com; 'Chiusano Joseph'; soa-rm@lists.oasis- 
> open.org
> Subject: Re: [soa-rm] David Linthicum Says: "ESB versus Fabric.Stop  
> It!"
>
> This stuff appears to be off topic for a reference model.
>
> These layers are extremely implementation oriented; and I submit,
> somewhat arbitrary. There is more in life than sending messages!
>
> Frank
>
> On May 23, 2005, at 6:47 PM, Michael Stiefel wrote:
>
>
>> +1
>>
>> Michael Stiefel
>>
>> At 01:31 PM 5/23/2005, Vikas Deolaliker wrote:
>>
>>>
>>> One could potentially map the SOA levels discussed in this blog to
>>> layers in a SOA-RM.
>>>
>>> Layer 1: Messaging/Queing with routing and transformation of
>>> messages. The endpoints for this layer are transport endpoints.
>>>
>>> Layer 2: Mediation Layer or Brokering Layer. The endpoints to this
>>> layer are the service endpoints. Endpoints are discovered using a
>>> discovery protocol (like DNS).
>>>
>>> Layer 3: Session Layer. The endpoints to this are session
>>> endpoints. Session endpoints can be all on one service endpoint or
>>> multiple.
>>>
>>> Layer 4: Process Layer. This is the choreography/orchestration
>>> layer at which new services can be developed.
>>>
>>> The RM then would need to define the notion of protocol data unit
>>> that traverses up/down and in between two of these stacks.
>>> (analogous to OSI).
>>>
>>> Thanks
>>> Vikas
>>>
>>> From: Chiusano Joseph [mailto:chiusano_joseph@bah.com]
>>> Sent: Monday, May 23, 2005 4:19 AM
>>> To: soa-rm@lists.oasis-open.org
>>> Subject: [soa-rm] David Linthicum Says: "ESB versus Fabric.Stop It!"
>>>
>>> Forwarding a very interesting and pertinent piece[1] from David
>>> Linthicum's (CTO of Grand Central) blog, titled "ESB versus Fabric.
>>> Stop It!". David also discusses 6 different "levels" of SOA,
>>> ranging from simple single point-to-point SOAP messages (Level 0)
>>> to SOA that incorporates orchestration (Level 5).
>>>
>>> Joe
>>>
>>> [1] http://www.webservices.org/index.php/ws/content/view/full/63539
>>>
>>> Joseph Chiusano
>>> Booz Allen Hamilton
>>> Visit us online@ http://www.boozallen.com
>>>
>>>
>
>
>