Bluetooth™ and Java™ Technologies

in the Wireless EnvironmentMichael T. Portwood, MS

President & CEO

Exuberance, LLC

Agenda

• What is Bluetooth™ wireless technology– Technology Overview– Weaknesses– Strengths

• What is Jini™ technology• Bluetooth, Jini™ technology, and the Wireless

Environment• Conclusion• Question & Answer

What is Bluetooth™Wireless Technology Overview

• Technology started by Ericsson• Named after 10th century Viking king

(Harald Blatand)• A global wireless technology specification• “Always on” communication• Radio frequency based• Inexpensive• Intended for …

– Portable devices– Desktop machines– Peripherals

Bluetooth™ Wireless Technology Details

• Baseband protocols– Circuit switching– Packet switching

• Uses 24 GHz globally available unlicensed ISM radio band• Effective range is 10 meters• Slow communication rate (721Kbps)• Small number of stations

– 8 devices / piconet– 3 voice channels

• Secure– Spread spectrum

Comparison ofWireless Technologies

Feature & Function Infrared 802.11Wireless LANs

HomeRF Bluetooth™

Connection Type Infrared, narrow beam

Spread spectrum

Spread spectrum

Spread spectrum

Spectrum Optical850 nm

RF

2.4 GHz

RF2.4 GHz

RF

2.4 GHz

Transmission Power 100mW 100mW 100mW 1mW

Data Rate 16Mbps 1Mbps,

2Mbps

1Mbps,

2Mbps

1Mbps

Range 1 meter 100 meters Typical home 3 meters

Supported Devices 2 127 8

Voice Channels 1 VOIP 6 3

Addressing 32 bit physical ID

48 bit MAC 48 bit MAC 48 bit MAC

Bluetooth™ Technology Strengths

• Inexpensive

• Superior range compared with IR

• Omnidirectional, not requiring line of sight

• Designed for ad hoc networking

• Both voice and data channels

• Well defined specification

• Large number of implementing companies

Bluetooth™ Technology Weaknesses

• Slow communication rate (1 Mbps)

• Short networking range

• Limited number of network connections

• Large and complex specification(over 1000 pages)

Bluetooth™ Wireless Technology Application Areas

• Pure computing applications– Presentations– Card Scanning– Synchronizing Data– Remote Synchronization– Printing– Scanners

• Ubiquous Applications– Communicator platforms– Electronic Books– Travel– Home Entertainment

• System Applications– In-vehicle systems

– Payment Systems

– Behavior Enforcement

– Collaboration

– Mobile E-commerce

What is Jini™ Technology

• Jini™ Technology is designed for reliable distributed computing

• Features– Simplicity– Reliability– Scalability

What Jini™ Technology is not

• Jini is not a name server

• Jini is not JavaBeans or Enterprise JavaBeans (EJBs)

• Jini is not RMI

• Jini is not a distributed operating system

Five Key Featuresof Jini™ Technology

• Discovery

• Lookup

• Leasing

• Remote Events

• Transactions

Discovery

• Discovery is the process of finding available lookup services

• The Jini discovery protocol is the means by which Jini-aware code finds Jini communities

Jini™ Discovery Protocols

• Multicast Request Protocol

• Multicast Announcement Protocol

• Unicast Discovery Protocol

Lookup

• Lookup refers to the things that you can do with the lookup services that are determined via discovery

• Lookup is similar to a name server– A process– Keeps track of all services that have joined a Jini

community

• Differs from a name server– Richer set of semantics than provided by traditional

name server

Lookup Actions

• Publishing a Service

• Downloading a Proxy

• Finding a Service

Leasing

• Leasing refers to the process of allocating resources to community members

• Leases are granted for a specified periodof time

• Addresses problems with network fragility

Remote Events

• Remote event is a technique for members of the community to notify one another of change

• Asynchronous notifications

• Consistent with events used in Java

Differences BetweenLocal and Remote Events

Local Events– Easier to deliver events

in the order that they were generated

– Always delivered

– Cost of delivery is low

– The sender knows that it can safely deliver the event to the consumer

Remote Events– Difficult to deliver

events in the order that they were generated

– Events may be undelivered

– Cost of delivery is high– The sender does not

know if it can safely deliver the event to the consumer

Transaction

• A transaction is a unit of work

• Transactions are used to complete complex units of work that may fail before complete

• Two phase commit

• Transactions are not heavily used in Jini™ applications

Transaction (cont.)

• Transaction provide…– Atomicity– Consistency– Isolation– Durability

Jini™ Key Concept Overview

• Discovery and Lookup establish a Jini community• Leasing helps Jini communities ensure stable, self

healing, and resilient networks in spite of inevitable network failure

• Events help Jini communities asynchronously communicate

• Transactions help successfully complete complex operations and provide resolution for incomplete operations

How Bluetooth™ Complements Jini™ Technology

• The key concepts found in Jini™ technology are found in Bluetooth™ wireless technology

• Bluetooth™ technology is hardware what Jini™ technology is to software– Platform independent– A “standard”– Widely accepted

Bluetooth™ and Jini™

• Both Bluetooth and Jini work well together– Ad hoc networking– Hardware specification complements software

specification, and visa versa– Broadly accepted technologies

Using Jini™ Technology

Additional Resources

• Bluetooth™ Wireless Technology– www.bluetooth.com

• Jini™ Technology– www.jini.org– www.javasoft.com

Conclusion

• Bluetooth™ and Jini™ technologies compliment one another

• Bluetooth™ technology excels at short duration ad hoc networking

• Jini™ technology complements Bluetooth™ Wireless Technology

• Many of the features of Jini™ technology can be found within the Bluetooth™ specification

Question & Answer

For Additional Information

• World Wide Web site– www.exuberance4me.com

• Presentation

• Presentation notes

• E-mail contact– portwood@exuberance4me.com