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New Technologies
Wireless Communication
Really Personal Computers
Network Object-Oriented Processing
The Changing Internet
The Next Big Thing
Wireless Communication
• Site Wireless Networking
• 802.11– For large site networks with many stations
• Bluetooth– For a few devices close to one another– Personal area networking
• May Interfere with Each Other if Both are Implemented
Wireless Communication• Metropolitan Wireless Networking
– For an urban area– Exists now, but slow (around 9,600 bps)– Soon 100 kbps– Megabit (up to 3 Mbps) services coming– Will make notebooks, etc. far more useful
• Satellite Wireless Networking– Megabit speeds anywhere
Wireless Communication
• Cellular Systems– Service area is broken up into several small
areas called cells
Wireless Communication
• Cellular Systems– Within each cell, there is a cellsite that
transmits to and receives from cellular devices
Cellsite
Wireless Communication• Cellular Systems
– Channel reuse. Channels can be reused in non-adjacent cells
No
No
YesNo
Yes
No
No
Yes
No
UsesChannel
232
Can ReuseCh. 232?
Channel 232Used in 4 cells
Wireless Communication• Cellular Systems
– Channel reuse is very important because available frequencies are very limited
Wireless Communication
• The Wireless Revolution– New freedom for users– Anything, anytime, anywhere– Likely to spawn new applications
Really Personal Computing
• Both Desktop PCs and Notebook PCs are Large– This limits their portability
Really Personal Computing
• Many Future Access Devices Will be Smaller– Personal digital assistants (PDAs)– Cellphones– Etc.
Really Personal Computing
• New “Form Factors”– Size and shape
Cellphone Access
• Cellphones will be Very Popular for Internet Access
– Cellphones are very widespread
• In Japan, the number of cellphones passed the number of wired phones in early 2000
• This is happening in other countries aswell
• The U.S. is somewhat behind becauseit did not settle on the world cellphonestandard, GSM
Cellphone Access
• Cellphones will be Very Popular for Internet Access
– Almost all cellphones are now being built with Internet access capability
– International Data Corporationpredicts that by the end of 2002there will be more wirelessdevices accessing the Internetthan wired devices; cellphoneswill be the most popular
Cellphone Access
• Starting to have small displays capable of showing a few lines of data
• Good for short messages
• Good for data retrieval ifquery is very targeted
• May be supplemented with voicegeneration so that cellphones canspeak the answer
Cellphone Access
• Wireless Access Protocol (WAP)
– Emerging standard for cellphone web access
– Also for other small devices, such as personal digital assistants (PDAs)
Cellphone Access
• Wireless Markup Language (WML)
– Way of formatting webpagesfor small displays
– Simpler than HTML
– Reformatting may be expensive
– Part of WAP
Cellphone Access
• Wireless Access Protocol (WAP)
– Device will communicate over the Internet with WAP server via WAP protocols rather than with webservers directly
WirelessCarrier
WAPProtocols
WAP Protocols
WAPServer
Cellphone Access• Wireless Access Protocol (WAP)
– WAP server may get content from full webserver using full webservice protocols (HTTP, TCP), probably translating webpages to WML
WirelessCarrier WAP
Server
Webservice Protocols
Full Webserver
The Problem of Input
• Keyboards
– Cannot be too small and still allow typing
• Voice Input
– Not very accurate, especially inreal (noisy) environments
– Not private
Network Object-Oriented Processing
• Traditional Object-Oriented Programming– Programs consist of many objects (forms,
buttons, etc.)– Objects send messages to one another to ask
others to do certain tasks by executingmethods
OBJ
OBJOBJ
OBJ
Message
Network Object-Oriented Processing• Network Object-Oriented Programming
(NOOP)– Objects can run on multiple machines– Still communicate by sending messages
OBJ
OBJ OBJ
OBJ
OBJ
OBJ
Message
Network Object-Oriented Processing
• NOOP takes advantage of available capacity on computers on the network– If computer has idle capacity, it will be sent
objects
OBJ
OBJ OBJ
OBJ
OBJ
OBJ
Network Object-Oriented Processing
• NOOP Standards are Needed for Object-Object Communication– Microsoft’s standards are DCOM and .NET– CORBA is a competing consortium standard
OBJ
OBJ
OBJ
OBJ
OBJ
OBJ
The Changing Internet
• Today’s Internet– Throughput is too low
– Delays (Latencies) are too long
– Reliability is too slow
• Need a “Business Class Internet”– Faster
– Lower Latency
– High reliability
The Changing Internet
• Two Classes of Service?– Regular versus Business Class?– Haves versus Have-Nots?
The Changing Internet
• Speeds– Gigabit to the desktop– Will make entirely new applications possible– Internet2 (Abeline)
The Next Big Thing
• The PC Revolution of the 1980s was not anticipated
• The Internet Revolution of the 1990s was not anticipated
• Will the future simply be an extension of the past, or will there be a Next Big Thing?
