29-01-2013, 03:59 PM
Wireless USB
[attachment=48779]
Overview
The Universal Serial Bus (USB), with one billion units in the
installed base, is the most successful interface in PC history.
Projections are for 3.5 billion interfaces shipped by 2006.
Benefiting from exceptionally strong industry support from
all market segments, USB continues to evolve as new
technologies and products come to market. It is already
the de facto interconnect for PCs, and has proliferated into
consumer electronics (CE) and mobile devices as well.
USB enjoys strong brand recognition, has a well-recognized
logo, and is supported by an experienced governing body–
the USB Implementers Forum (USB-IF).
Wireless USB will build on the success of wired USB,
bringing USB technology into the wireless future. Usage
will be targeted at PCs and PC peripherals, consumer
electronics and mobile devices. To maintain the same
usage and architecture as wired USB, the Wireless USB
specification is being defined as a high-speed host-todevice
connection. This will enable an easy migration
path for today’s wired USB solutions.
Usage Models
The growing use of wireless technology in PC, CE, and
mobile communications products, along with the convergence
of product functionalities, calls for a common wireless
interconnect standard. The standard needs to work well
with products and usage models from all three industries.
To better understand what’s driving the need for a common
standard, we’ll examine how these products will soon be
used in home and business environments. We’ll also
consider the rise of “dual-role” devices that include both
host and device capabilities.
Home Usage Scenarios
The trend towards smaller form factors, portability and
mobility in consumer electronics devices has led to the
emergence of new classes of products. These products
have rich functionality, multimedia capabilities, and require
connection to other AV devices for display, editing, listening,
sharing, and downloading of content. Within the home,
for instance, a family may have a digital video camcorder,
digital still camera, portable MP3 player, PDA, tablet PC,
wireless speakers, and personal video display device.
Office/Business Usage Scenarios
Connectivity issues and other inconveniences of wired
connections can hurt productivity and slow the adoption
of new devices within the work environment. Users of mobile
computers and PDAs particularly face connection challenges
as they move from place to place and want to use printers
and other devices. Wireless USB could simplify their lives
while providing a time-saving, high-speed connection that
enhances productivity (see Figure 2). In this section, we give
some typical scenarios of how Wireless USB could enhance
connectivity in the office.
Dedicated Office Services
Executives, managers and heavy users need faster, dedicated
services in their office rather than those shared on
the network. With Wireless USB, devices such as inkjet
and laser printers, scanners, external storage devices,
and PC cameras can quickly connect and exchange data
at high speed. Top Wireless USB uses will probably include:
simultaneous and frequent-use mass storage for data backup,
printer connectivity, scanner connectivity, and PDA
or cell phone synchronization.
Dual-role Devices
A new class of Wireless USB dual-role devices is projected
to eliminate wires in many usage scenarios and enable new
uses not previously possible. These devices will offer both
limited host and device capabilities, similar to that experienced
with USB On-The-Go. (USB OTG is the wired USB
specification defining dual-role devices which can act as
either hosts or peripherals, and can connect to PCs or other
portable devices through the same connector.) Figure 3
shows some dual-role device usage scenarios. More detailed
descriptions of various scenarios are also provided.
Technology Requirements
Topology
The fundamental relationship in Wireless USB is the “huband-
spoke” topology, as shown in Figure 4. The host initiates
all the data traffic among the devices connected to it, allotting
time slots and data bandwidth to each device connected.
These relationships are referred to as clusters. The connections
are point-to-point and directed between the Wireless
USB host and Wireless USB device. The main difference here
from wired USB case is that there are no hubs present in the
connection topology. The Wireless USB host can logically
connect to a maximum of 127 Wireless USB devices.
Security and Device Association
Wireless USB security will be designed to deliver the same
level of security as wired USB. Connection-level security
between devices, for instance, will be designed to ensure
a device is associated and authenticated before operation
of the device is permitted. Higher levels of security involving
encryption will be implemented at the application level. An
important goal will be to ensure that processing overhead
supporting security does not impose noticeable performance
impacts or device cost.
In regards to device association, one of the primary objectives
when implementing Wireless USB will be to make sure
it enables easy installation and operation. In a way, wireless
technology presents new challenges to ease of use. That’s
because wired connections provide the user with very direct
expectations. In essence, when they plug a device in,
(i.e., when the wire is connected), the user can see the
connection is made (or not made if the plug doesn’t fit).
Wireless connections on the other hand, due to environmental
characteristics, may establish connection paths that
are not obvious. In fact, it may not be obvious when a
device is connected.
[attachment=48779]
Overview
The Universal Serial Bus (USB), with one billion units in the
installed base, is the most successful interface in PC history.
Projections are for 3.5 billion interfaces shipped by 2006.
Benefiting from exceptionally strong industry support from
all market segments, USB continues to evolve as new
technologies and products come to market. It is already
the de facto interconnect for PCs, and has proliferated into
consumer electronics (CE) and mobile devices as well.
USB enjoys strong brand recognition, has a well-recognized
logo, and is supported by an experienced governing body–
the USB Implementers Forum (USB-IF).
Wireless USB will build on the success of wired USB,
bringing USB technology into the wireless future. Usage
will be targeted at PCs and PC peripherals, consumer
electronics and mobile devices. To maintain the same
usage and architecture as wired USB, the Wireless USB
specification is being defined as a high-speed host-todevice
connection. This will enable an easy migration
path for today’s wired USB solutions.
Usage Models
The growing use of wireless technology in PC, CE, and
mobile communications products, along with the convergence
of product functionalities, calls for a common wireless
interconnect standard. The standard needs to work well
with products and usage models from all three industries.
To better understand what’s driving the need for a common
standard, we’ll examine how these products will soon be
used in home and business environments. We’ll also
consider the rise of “dual-role” devices that include both
host and device capabilities.
Home Usage Scenarios
The trend towards smaller form factors, portability and
mobility in consumer electronics devices has led to the
emergence of new classes of products. These products
have rich functionality, multimedia capabilities, and require
connection to other AV devices for display, editing, listening,
sharing, and downloading of content. Within the home,
for instance, a family may have a digital video camcorder,
digital still camera, portable MP3 player, PDA, tablet PC,
wireless speakers, and personal video display device.
Office/Business Usage Scenarios
Connectivity issues and other inconveniences of wired
connections can hurt productivity and slow the adoption
of new devices within the work environment. Users of mobile
computers and PDAs particularly face connection challenges
as they move from place to place and want to use printers
and other devices. Wireless USB could simplify their lives
while providing a time-saving, high-speed connection that
enhances productivity (see Figure 2). In this section, we give
some typical scenarios of how Wireless USB could enhance
connectivity in the office.
Dedicated Office Services
Executives, managers and heavy users need faster, dedicated
services in their office rather than those shared on
the network. With Wireless USB, devices such as inkjet
and laser printers, scanners, external storage devices,
and PC cameras can quickly connect and exchange data
at high speed. Top Wireless USB uses will probably include:
simultaneous and frequent-use mass storage for data backup,
printer connectivity, scanner connectivity, and PDA
or cell phone synchronization.
Dual-role Devices
A new class of Wireless USB dual-role devices is projected
to eliminate wires in many usage scenarios and enable new
uses not previously possible. These devices will offer both
limited host and device capabilities, similar to that experienced
with USB On-The-Go. (USB OTG is the wired USB
specification defining dual-role devices which can act as
either hosts or peripherals, and can connect to PCs or other
portable devices through the same connector.) Figure 3
shows some dual-role device usage scenarios. More detailed
descriptions of various scenarios are also provided.
Technology Requirements
Topology
The fundamental relationship in Wireless USB is the “huband-
spoke” topology, as shown in Figure 4. The host initiates
all the data traffic among the devices connected to it, allotting
time slots and data bandwidth to each device connected.
These relationships are referred to as clusters. The connections
are point-to-point and directed between the Wireless
USB host and Wireless USB device. The main difference here
from wired USB case is that there are no hubs present in the
connection topology. The Wireless USB host can logically
connect to a maximum of 127 Wireless USB devices.
Security and Device Association
Wireless USB security will be designed to deliver the same
level of security as wired USB. Connection-level security
between devices, for instance, will be designed to ensure
a device is associated and authenticated before operation
of the device is permitted. Higher levels of security involving
encryption will be implemented at the application level. An
important goal will be to ensure that processing overhead
supporting security does not impose noticeable performance
impacts or device cost.
In regards to device association, one of the primary objectives
when implementing Wireless USB will be to make sure
it enables easy installation and operation. In a way, wireless
technology presents new challenges to ease of use. That’s
because wired connections provide the user with very direct
expectations. In essence, when they plug a device in,
(i.e., when the wire is connected), the user can see the
connection is made (or not made if the plug doesn’t fit).
Wireless connections on the other hand, due to environmental
characteristics, may establish connection paths that
are not obvious. In fact, it may not be obvious when a
device is connected.