PUBLIC PACKET SWITCHING


Public Packet Switching (PPS) is a new

Pacific Bell service for customers who

require data networking at lower costs.

Essentially, Public Packet Switching

costs to the user are based upon how

much information is sent on the

network, rather than how long the user

is connected.




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Public Packet Switching offers a public

"shared" environment for data, much as

the voice environment has shared for

over 100 years.  This new public

service is well suited for terminals

that need access to remote computers. 

Users with low volume or "bursty" data

traffic will find Public Packet

Switching very cost-effective.




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The Pacific Bell Public Packet

Switching network conforms to the CCITT

standards for X.25 networks.  It also

connects to other packet switching

networks using the CCITT X.75 protocol,

thus giving users potential access to

host computers and terminals in other

service areas and states.  This service

is capable of handling low speed

terminal traffic as well as high speed

host computer traffic.  As a result,
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many computers and network switches

already have the built-in capability to

interface with the Public Packet

Switching network.


The technology behind Public Packet

Switching involves placing data into

"segments", usually 128 bytes in size,

forming multiple segments into a

"packet" of variable length, and

sending the packets through the network


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with many other packets from different

users, to any computer or terminal

hooked on the public network.  A device

called a "PAD" (packet assembler

disassembler) is needed at the terminal

and host computer ends to convert the

data into the X.25 protocol. 

For those users who need added

security, there is also a Closed User

Group feature with Public Packet

Switching that allows for private

networks within the public network. ^

The exciting part of this new service

is that once a terminal user is on the

Public Packet Switching network for

either business or personal use, he or 

she will have low- cost, usage-based 

access to any connected information 

provider or host computer to which 

he or she subscribes.



PUBLIC PACKET SWITCHING IS PENDING   

 CPUC AND FCC REGULATORY APPROVAL   
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