RE: activity context & context poll

Mark,

 

    Thanks for your e-mail. I am exploring the current status 
of context at w3c. In the meantime, if you want, I could start collecting some 
thoughts around context. 

 

    I have a general question to all of us - What does a 
context mean ? What should it contain ? May be we could come up with a 
strawperson context within a couple of weeks and improve upon 
it.

 

cheers

  
-----Original Message-----
From: Mark Little 
  [mailto:]
Sent: Monday, April 09, 2001 6:57 
  AM
To: Krishna Sankar; bt models
Subject: Re: activity 
  context

  
 

  
    
    I am a fan of context and by having one for *all* 
    interactions, we can promote more of the stateless services. Here are 
    some of my thoughts on context:

  
Yes, it would be good if we could make progress on the context format. 
  The basic structure could pass common features (such as the coordinator 
  reference, timeout etc) in a strongly types fashion, and we can then allow 
  model specific data in a less strongly typed manner (e.g., a CORBA any in the 
  example), because any user of that data must check the type structure of the 
  context anyway.

  
    
    1.    Context could be viewed as a set 
    of attribute assertions, some of them signed and even 
    encrypted.

  
Agreed. There's nothing to say that the model specific data couldn't be 
  encrypted, for example.

  
    
    2.    Context is information other than 
    the actual transaction data and can include the user credentials, any 
    previous state, time of day, geographic location of the calling entity, 
    ...

  
I think that the general context should be a series of specific context 
  instances, one for transactions (which only talks about transaction related 
  stuff), one for security, etc.

  
    
    3.    The context of course would be an 
    XML document. I was thinking of something like :

    
        <context>

    
            
    <actionType>xxxx</actionType>

    
            
    ..

    
        </context>

    
    4.   Yes, context need not be that 
    elaborate, but we do need to divide context into related graphs so that 
    later the systems can use XPath/XPointer to get specific set of information 
    they need.

    
 

    
    5.    FYI, I think context is much more 
    important from a web services point-of-view and if W3C ever standardized the 
    context, we could use it at that time. For now we should be able to define a 
    simple context graph which is relevant to our 
  work.

  
Agreed. Do you know where the W3C is with this at the 
  moment?

  
    
    6.    If we start defining context 
    now,  i.e. what pieces of data do we need , we could "normalize" the 
    structure after we have identified say 70% of the 
    information.

  
All the best,

  
 

  
Mark.

  
 

  
----------------------------------------------
Dr. 
  Mark Little ()
Transactions Architect, 
  HP Arjuna Labs
Phone +44 191 2064538
Fax   +44 191 
  2064203