Introduction to Tandem X.25 Capabilities

Internetwork-Related Standards
What is X.25?
065307 Tandem Computers Incorporated 1–9
Internetwork-Related
Standards
The interfaces that connect one network to another are also regulated by CCITT
standards, as described below.
X.75
The X.75 standard defines the procedures that must be followed to connect public
packet-switching data networks through a gateway interface. The X.75 standard
applies to international circuits; however, it does not apply to the connection of private
networks (see Figure 1-6).
ISO 8208 and ISO 7776
The ISO 8208 and ISO 7776 standards define the procedures that must be followed to
connect public data networks to private networks.
ISO 7776 specifies additional parameter values for DTE implementation. These values
are related to LAPB (Link Access Procedure Balanced), and provide features that
facilitate connecting public data networks to private networks.
Figure 1-6. Standards for Connecting Networks
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Public Data Network
Private Network
X.75
ISO 8208 and
ISO 7776
ISO 8208 and
ISO 7776
Public Data Network