An Underview of the class so far

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An Underview of the class so far

• Larry Rudolph
• Pervasive Computing
• Oct 4, 2001

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Three Ways of Distributed Communication

• Graffiti Put data in agreed upon place
• Shared Memory Shared File
• Telephone Direct, two-way connection
• Pipes, Sockets, Message-passing
• Your place or mine?
• Stop what your doing
• Events, Procedure Call, HTTP Post
• Establish, Perform, Return Ans Destroy

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Three Ways of Pass Information

• Shared Memory not relevant to us now
• Sockets
• Agreed order or tagged
• Server stays alive (and can remember past)
• Procedure Call
• Agreed order or tagged
• Local storage destroyed after return

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Procedure Call

• Specify procedure name, then give params
• Read(fileDesc, buffer, length)
• Printf( This is the d time I said s,n,Damn)
• Currying f(a,b,c) for a1, 2, or 3
• Same as three different functions
  F1(b,c), F2(b,c), F3(b,c)
• Events Different function for each event
• Or same function, different param value

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Galaxys Method

• Single Procedure Call
• First parameter function name
• Remaining parameters are tagged data

Some Server (money.lcs.mit.edu)
Galaxy
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Galaxys Method
http//money.lcs.mit.edu/rudolph/interface.cgi
In rudolph/cgi-bin
Interface.cgi
Executes A Program Specified in the URL
F1
HTTPPost
F2
F3
Procedure Specified by action param
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Parameters to procedure

• Tagged with frame
• Subtagged within frame
• Each procedure can have different number of
  parameters
• Your choice to pass by order or by tag

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Major Complication

• Not all parameters may be specified
• Choices
• Dont call until all are specified
• Annoying to force user to say them all
• Where to save them?
• Call with partial list
• Save them in procedure (provided it stays alive)
• Return to galaxy as history param
• Thanks for the memories

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Strategy

• Decide on Procedures (e.g. actions)
• Make list of corresponding words values
• Decide on Parameters (e.g. keys)
• Make list of corresponding words values
• Decide on how to handle missing params
• Make list of sample sentences
• Example word per key/command

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Speech Builder Warnings

• Dont hit the delete, unless you are sure
• Edit is to right of thing (with too much
  separating space for my taste)
• Reduce is really useful
• Always get xml since you will probably delete the
  domain by accident
• Experiment and play