Thursday, March 30, 2006

Flying car ready for takeoff?



This summer, graduate students at the Massachusetts Institute of Technology will try to get an idea aloft that has intrigued people for decades: the flying car.

Terrafugia, a start-up created by Lemelson-MIT Student Prize winner Carl Dietrich and colleagues at MIT's Department of Aeronautics and Astronautics, is aiming to show off what it calls the Transition "personal air vehicle," an SUV with retractable wings, to the EAA AirVenture Conference in Oshkosh, Wis., at the end of July.

The Transition is designed for 100- to 500-mile jumps. It will carry two people and luggage on a single tank of premium unleaded gas. It will also come with an electric calculator (to help fine-tune weight distribution), airbags, aerodynamic bumpers and of course a GPS (Global Positioning System) navigation unit.

Full report can be found at here

Sunday, March 26, 2006

Message Oriented Middleware Communication Modes

The factors I depicted out for communication between peers are:
{Synchronous, Asynchronous, Transient, Persistent, Ack time)
in turn acknowledge enumeration can be made from ACK ENUM {Immediate, before response, response based, any}

We can make different combination of them,

  • Persistent Asynchronous

  • Persistent Synchronous

  • Transient Asynchronous

  • Transient Synchronous

  • Recipient based Transient Synchronous

  • Delivery based Transient Synchronous

  • Response based Transient Synchronous


Persistent storage in pervasive environment can be defined as a storage on a mobile entity or set of mobile entities, such that demise of MH(s) should not result in loss of message.

Such that for any two entites, we need to define Sync/Async at A, Sync/Async at B, Persistence at A/Middleware/B, Message Acknowledgement ACK ENUM.

Friday, March 24, 2006

Phew! Mustang is out

Phew!
Mustang is out. To check out 10 hot things in mustang, go to Danny's weblog's entry
The 10 Things You Need to Know About Java SE 6 'Mustang'

Monday, March 20, 2006

Amazing/Amusing Stuff people do in Asynchrous Middlewares

Well, to avoid setup, search and registration confirmation latency while listening to a pub/sub in a new region. Virtual clients can queue up previous notifications and upon entities arrival they can dump the queued messages to newly arrived entity.

Good Points
  • In case pub/sub JMS is not centralized then you can automatically discover other peers in the region. This would work in a centralized case also. But mobile framework I have supports peer MH (Mobile Host) discovery, hence first good point is not so good.
  • A very good take can be in case queued notifications contains intermediate hop listings, then MH can update channel entires in routing tables with listed ones. It is a very good point I should say.

Bad Point
  • Security is a concern, if entities are required to get only authenticated notifications only then things w'nt work it out as what newly arrived entity would be receiving are notification targeted to other entities.

Service Availability Estimation vs Service Discovery

I never got belief in this that computing time to be devoted in service
availability estimation rather than service discovery. A fact tells latency/overhead in 10 bytes of network communication is equal to 100000 CPU cycles. Huhh!!! Big figures, but look at the overhead involved in all this estimation if your prediction goes false, after all algorithms (Linear scaling or Bin) works on past records of service availability or service demise.

A good concept to take from service availability estimation is a fuzzy logic crieteria to compute device availability scale.

Thursday, March 09, 2006

Mobile Service Buses

Mobile devices can work as service buses by consuming and transfering data collected from fixed/mobile sensors deployed in the region. Taking this as a PRD, the essential features required would be support for Asynchronous Communication, Support for Service Discovery, Need to differentiate between Service and Device discovery. The framework adds device discovery, but I am not very sure about whether the framework supports the Service Discovery. Let me think........

Well! after an intensive thought on the framework, service discovery is supported, but the service query APIs are not formulated, may be other service dimensions might also be in unstructured format, but yeah scalability is there and framework can have all the functionalities, I am very sure about this.

About asynchronous communication, a customize self organizing pub/sub service can help me to post up the functionality. But I need to investigate on that.