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ND 10770 Coloured Books Yellow Book Transport Service (YBTS)¶

Introduction¶

ND Coloured Books Yellow Book Transport Service, YBTS, is a set of library routines for those who need to write their own data communication software. Although it is a network-independent service, the current version of YBTS supports only the X.25 packet level interface.

Its official name is 'Network Independent Transport Service,' but in OSI terms it is more correct to call it a 'Network Independent Network Service.'

The current implementation of YBTS consists of a set of interfacing routines using XMSG to communicate with the X.25 packet level interface. There are two sets of library files; one set for Fortran and Planc ND-500 versions, and one corresponding set for the ND-100 versions.

Features¶

Can be used from Planc or Fortran on any of the ND-100 or ND-500 computer ranges
YBTS can access the X.25 packet level accessible via COSMOS.
The provision of a flow-control mechanism, which means that the sending rate is adapted to the receiving rate.

Product Description¶

YBTS is a tool for data transfer between ND computer systems and non-ND computer systems.

YBTS offers a subnetwork independent interface that is used by the higher level Coloured Books protocols. However, YBTS does not qualify as a 'true' OSI Level 4 Transport service.

Requirements¶

ND-500, ND-100, ND-COMPACT, or ND-SATELLITE computer systems
SINTRAN III version J or later, generated for XMSG
Access to X.25 software, COSMOS X.25 Option version B locally or via an XMSG/COSMOS connection.

Documentation¶

Coloured Books Programmer Guide .................. ND-60 221