A SEMINAR ON Certified Wireless USB

SABITH P. SOE-CUSAT

• INTRODUCTION• RADIO ENVIRONMENT• HIGH-LEVEL ARCHITECTURE • CONCLUSION

• INTRODUCTION– WIRED USB– REASONS FOR WIRELESS USB– FUTURE OF MOBILITY

• RADIO ENVIRONMENT• HIGH-LEVEL ARCHITECTURE • CONCLUSION

• WIRED USB• OVERVIEW

– EASE OF USE» The real plug and play

– PORT EXPANSION» Interconnects were optimized for two point products» There was need for a bi-directional, low cost,low to mid speed

peripheral bus

• WIRED USB– Technical Details

• Host/Slave Connection– PC (host) manages all transfers; peripherals (slave) just responds– Supports 127 slaves per host

• Physical Connection– Four wire connection

» Two wires for power (+5 and GND)» Two wires (twisted pair) for synchronous serial data

– Computer supplies power (up to 500 mA)

• Data Rates– Low Speed: 1.5 Mbps (Keyboards, mice, etc.)– Full Speed: 12 Mbps (USB1.1 max speed)– Hi-Speed: 480 Mbps (USB2.0 max speed)

• INTRODUCTION– WIRED USB– REASONS FOR WIRELESS USB– FUTURE OF MOBILITY

• RADIO ENVIRONMENT• HIGH-LEVEL ARCHITECTURE • CONCLUSION

• Issues Of Wired USB– Wires are restrictive– Multiple wires can be a hassle– Wires are slower than wireless solutions

• Inadequacy of current wireless solutions– Bluetooth

• Bandwidth of 3 Mbps not enough for higher demand applications (Video, HDTV, Monitor)

– WiFi• Expensive• High power usage in mobile devices

• INTRODUCTION– WIRED USB– REASONS FOR WIRELESS USB– FUTURE OF MOBILITY

• RADIO ENVIRONMENT• HIGH-LEVEL ARCHITECTURE • CONCLUSION

Reliably…Reliably…

And And SecurelySecurely

Delivered to youDelivered to youEasily…Easily…

Access toAccess toAnythingAnythingYou want…You want…

WhenWhenYou want it…You want it…

WhereWhereYou want itYou want it

• INTRODUCTION• RADIO ENVIRONMENT• HIGH-LEVEL ARCHITECTURE• CONCLUSION

• INTRODUCTION• RADIO ENVIRONMENT– PHY characteristics– WiMedia and MAC

• HIGH-LEVEL ARCHITECTURE• CONCLUSION

• UWB Spectrum is not legal in all countries,whereas the USB-IF is still working with legal permissions

• Hi-speed at short range– 480Mbps (~3m)

• Scalable performance

• INTRODUCTION• RADIO ENVIRONMENT– PHY characteristics– WiMedia and MAC

• HIGH-LEVEL ARCHITECTURE• CONCLUSION

• Chanel time : 65 millisecond superframes• Supports TDMA capabilities– Wireless USB uses this feature

• All wireless USB products need to be good WiMedia citizens– Primarily the goal of Wireless USB hosts

• INTRODUCTION• RADIO ENVIRONMENT• HIGH-LEVEL ARCHITECTURE• CONCLUSION

• Bandwidth– 480 Mbps @ ~3m– Scalable architecture and protocol

• Power management(Battery preservation)– Sleep/Listen/Wake conserve under operation– Tx/Rx power management

• Security (Secure connection)– Device secure assosiation and authentication– Low overhead minimize performance impact– Encryption

• Ease of use (Similar to wireless USB)– Easy installation& setup– Backward compatible to wired USB– Low cost implementation

Dual Role Dual Role DevicesDevices

Up to 127 devicesUp to 127 devices

Host scheduled dataHost scheduled datacommunicationscommunications

• USB Wire Replacement Technology• Matches data rate of

USB 2.0 (480 Mbps)• Hub-and-spoke connection relationship• Connection model is a wire replacement– Point-to-point connections– Between Certified wireless USB host

and peripheral

• Certified wireless USB cluster– Wireless USB Host with one

or more peripherals (up to 127 addressable devices)

• Certified Wireless USB clusters may co-exist within an overlapping spatial environment

• Effective power management was important design goal– Portable (battery powered) devices are very popular– No longer have a cable to deliver power

• Explicit host – controller transaction scheduling provides opportunities for power management– Host and device have explicit times when they are able to

transmit and receive– Radios can be ‘power managed’ at all other times

• Protocol designed from the ground up, optimized for a wireless medium – Power management– Security and association– Operating System support/class driver protocol maintained– Data throughput – Bandwidth allocation/isochronous support

• 75% efficient (352 Mbps) in dedicated environment• 66% efficient (160 Mbps out of 240 Mbps)

in shared environment

• INTRODUCTION• RADIO ENVIRONMENT• HIGH-LEVEL ARCHITECTURE– SECURITY AND ASSOSIATION– ENABLING PRODUCTS

• CONCLUSION

• Security’s job– Protect data in transit (loss of wires)– Encryption is used

• Association’s job– Connect the owner’s devices the way the owner

wants them connected

• Contains everything needed to make a secure communication

• Unique for each host device pairing

• INTRODUCTION• RADIO ENVIRONMENT• HIGH-LEVEL ARCHITECTURE– SECURITY AND ASSOSIATION– ENABLING PRODUCTS

• CONCLUSION

• PCI (or PCIe) based solutions– Can go in add-in card slot– Cardbus or Express Card solutions

• Wired USB dongle– Cabled ‘base station’ variety– Small ‘key’ solutions

Certified Wireless USBCertified Wireless USBHost Wire Adaptor: HWAHost Wire Adaptor: HWA

Certified Wireless USBCertified Wireless USBDevice Wire Adapter: DWADevice Wire Adapter: DWA

USB 2.0USB 2.0 USB 2.0USB 2.0

• Looks like a wireless hub• Single chip implementations can be integrated

directly into devices• Wired to wireless decrease data throughput

• Appears well designed; good support• Slow start of products– Will it really catch on?– More products need to be developed

• Promises a lot; will it deliver?• Security is very important

• USB 2.0 SPECIFICATION– USB-IF

• WWW.USB.ORG

• WUSB SPECIFICATION 1.0– USB-IF

• WWW.USB.ORG

QUESTIONS?