x.25 is an
ITU-T standard
protocol suite for the
DTE-
DCE interface in a
packet switched network, approved by
ISO. It defines standard
physical layer,
data link layer and
network layers (layers 1 through 3) of the
OSI model. It was developed to describe how data passes into and out of public data communications networks. It is
connection oriented[?] and has rigorous
error correction.
X.25 networks are still in use throughout the world although in decline, being largely supplanted by newer layer 2 technologies such as Frame relay, ISDN and ATM and the ubiquitous layer 3 Internet Protocol.
Document: ISO 8208.
based on FOLDOC