Browse Prior Art Database

Nonstandard Extension for Facsimile Transfer Protocol

IP.com Disclosure Number: IPCOM000111227D
Original Publication Date: 1994-Feb-01
Included in the Prior Art Database: 2005-Mar-26
Document File: 2 page(s) / 83K

Publishing Venue

IBM

Related People

Kreitzer, SS: AUTHOR [+4]

Abstract

Disclosed is a computer-based method for allowing enhancements to facsimile transfers, and for allowing remote access to computer resources, through provisions of the CCITT (International Telegraph and Telephone Consultive Committee) T.30 standard for user-defined nonstandard frames. Capabilities for providing a termination mode and a non-T.30 protocol are added. The termination mode allows voice messaging or modem functions to start at the end of image messaging, instead of simply terminating the telephone call at the end of the facsimile image transfer. The non-T.30 protocol permits various functions specified by system users. For example, a computer based system may remotely access the resources of a remote computer using this facility.

This text was extracted from an ASCII text file.
This is the abbreviated version, containing approximately 52% of the total text.

Nonstandard Extension for Facsimile Transfer Protocol

      Disclosed is a computer-based method for allowing enhancements
to facsimile transfers, and for allowing remote access to computer
resources, through provisions of the CCITT (International Telegraph
and Telephone Consultive Committee) T.30 standard for user-defined
nonstandard frames.  Capabilities for providing a termination mode
and a non-T.30 protocol are added.  The termination mode allows voice
messaging or modem functions to start at the end of image messaging,
instead of simply terminating the telephone call at the end of the
facsimile image transfer.  The non-T.30 protocol permits various
functions specified by system users.  For example, a computer based
system may remotely access the resources of a remote computer using
this facility.

      In a standard facsimile transfer, as documented in the T.30
standard, commands and responses, as well as messages, are exchanged
between the calling and called sides.  For example, after
communications are established in a facsimile transmission, the
called side may respond with a Digital Identification Signal (DIS)
code, followed by a Nonstandard Features (NSF) code, identifying its
capabilities.  The calling side may then specify an operating mode by
sending a Digital Command Signal (DCS) code, followed by a
Nonstandard Facilities Setup (NFS) code.  In this way, when two
machines with compatible nonstandard capabilities first begin
communicating, they negotiate to determine what will be done.

      Each of the NSF and NSS codes consist of a flag, followed by an
address, followed by a control, followed by a command, followed by
frame information field, followed by two CRC bits, followed by
another flag.  The command is used to distinguish the NSF and NSS
codes from each other and from other codes.  The frame identification
field may be used for any purpose desired by the user.  For example,
the frame identification field of the NSF code may be used to specify
an identification number, followed by available features, such as
compression types, termin...