PAD Services

Introduction

Recommendation X.29 is the protocol for the exchange of messages between the host and PADs.

Recommendation X.3 defines a set of parameters that control PAD operation. The following illustration shows the relationship between each of these recommendations.

Figure 6-1 PAD Support Protocols
HOST

Packet Switching

PAD

T

Network

 

 

 

X.25

 

X.25

X.28

 

 

 

 

 

X.3

 

 

X.29

 

 

PAD services and the HP 9000 host

All of the PAD services can be seen as a pipe through which data is passed from X.25 to the PTY (Pseudo Type) terminal and vice versa (see the illustration below). Terminal data is not modified, but the X.25 headers are stripped before data reaches the PTY.

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