Browse Prior Art Database

Bi-Directional, Full-Depth Communications on Token Ring Network

IP.com Disclosure Number: IPCOM000106337D
Original Publication Date: 1993-Oct-01
Included in the Prior Art Database: 2005-Mar-20
Document File: 2 page(s) / 64K

Publishing Venue

IBM

Related People

Joshi, M: AUTHOR [+3]

Abstract

Disclosed is a technique to transport information in a Token Ring LAN. The approach improves the quality of video while voice is quiet and improves quality of voice while video is still. For example, subsampling techniques are used to reduce video/voice traffic. This disclosure permits the subsampling to be reduced to improve quality. The subsampling may have resulted in the transmission of every other frame of the video. With this technique, every frame may be sent. The subsampling may have resulted in the transmission of every other line of the video. With this technique, every line may be sent.

This text was extracted from an ASCII text file.
This is the abbreviated version, containing approximately 53% of the total text.

Bi-Directional, Full-Depth Communications on Token Ring Network

      Disclosed is a technique to transport information in a Token
Ring LAN.  The approach improves the quality of video while voice is
quiet and improves quality of voice while video is still.  For
example, subsampling techniques are used to reduce video/voice
traffic.  This disclosure permits the subsampling to be reduced to
improve quality.  The subsampling may have resulted in the
transmission of every other frame of the video.  With this technique,
every frame may be sent.  The subsampling may have resulted in the
transmission of every other line of the video.  With this technique,
every line may be sent.

      This is achieved by allowing one of the stations (the sending
station) to transmit a packet with a predetermined information field
length (e.g., 96 bytes) to a target station (the receiver).  The
information field carries both voice and video subfields.  The packet
carries a unique frame code within the first two bits of the FC
subfield in the packet header.  The receiving station, upon
recognizing the unique FC code AND its own address in the Destination
Address (DA) subfield, removes the information field from the
incoming packet and inserts a return information field of the same
size (predetermined) into the packet.  A new Frame Check Sequence is
computed and appended to the frame.  The Address Recognized and Frame
Copied bits are set in the Ending Frame Status field.

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