Homework two

CS595 Pervasive Computing and Web Service

Due March 30, 2004



  1. Read the following papers:
        1/ Xian-He Sun and Vijay K. Gurbani, "Terminating telephony services on the Internet", to appear in IEEE/ACM Transactions on Networking, Summer 2004 (available in lecture web site).
        2/ Vijay K. Gurbani (Ed.) et al., "The SPIRITS (Services in PSTN requesting Internet services) Protocol", IETF Internet-Draft, http://www.ietf.org/internet-drafts/draft-ietf-spirits-protocol-07.txt

        Based on your understanding of the overall architecture presented and the PSTN detection points presented in [1,2], how would you provide the following application:

    Assume you want to maintain a log of all the incoming calls to your cellular phone.
           1.1 - Which detection points will you use for this service?
           1.2 - Provide a time-line diagram of the call flow.  This should indicate the sequence of events as they occur across Internet and the telephone network entities.
           1.3 - Provide a sample XML body for a subscription and subsequent notification.  The body must contain all the necessary information.  An XML schema is provided in [2].


  1. Read the following papers:

                  K. Chanchio, and X.-H. Sun, “Communication State Transfer for the Mobility of Concurrent Heterogeneous Computing,” accepted to appear in  IEEE Transactions on Computers (available in lecture web site).


Based on your understanding of the communication protocols, explain

         2.1 Why in the migrate() algorithm (Figure 5), line 5, we need to send both disconnection signal and peer-migrating message?

         2.2 What is purpose of the disconnection handler algorithm (Figure 6)? Why in some case it takes the disconnection action and some time not?


  1. Program Assignment


Problem Statement:

To understand the concept of web services, you need to design and implement one small web service. Also to test the functionality of web service you need to implement corresponding client part.


The Web Service should do some useful function. Again the purpose is to understand the concept of Web Service and not how intelligent your service is. So you can design any service but the minimum requirement is it should have some functions and any client can call these functions and get some useful return values. Each student should have different service (though they are simple functionalities) to get some different thoughts from all of you.


How to Start:

You need to understand the basic components of Web services like SOAP, WSDL and UDDI. You can select any language and any tool you want to get the functionality of SOAP, WSDL and to actually implement the service, but you have to be more specific about why you selected that tool. You can use .NET or Web Sphere or any other web service-hosting framework.


http://www.w3.org/2002/ws/ - general website for web services standards

http://www.w3.org/TR/soap/ - SOAP specification


http://www.w3schools.com/soap/default.asp- SOAP tutorial

http://www.w3schools.com/wsdl/default.asp - WSDL tutorial


http://java.sun.com/webservices/ - Java based web services

http://ws.apache.org/ - Apache open source for web services tools like SOAP and WSDL.


Evaluation Criteria’s:


Document part:

1.      What tools you selected and why?

2.      Where other places/Industry it is used?

3.      Conclusion and Thought about what you learned and how you approached this problem?


Demo part:

Show your client and Web Service. Show how it generates the WSDL file. If you have static IP (cool!!) then you can make your service available to the rest of the world. But if you do not have one, then don’t’ worry, I will check in your machine, with localhost option.



You can discuss with your friends and may get some installation help, but we need some form of uniqueness and your thoughts in your work.