Browse Prior Art Database

INTEGRATING A MAC "NOTIFICATION OF END OF TRANSMISSION" WITH A RELIABLE LLC DATA LINK LAYER THAT TRANSMITS MULTIPLE DATAGRAMS IN A SINGLE TRANSMISSION IN A PACKET DATA SYSTEM

IP.com Disclosure Number: IPCOM000008666D
Original Publication Date: 1998-Jun-01
Included in the Prior Art Database: 2002-Jul-02
Document File: 2 page(s) / 103K

Publishing Venue

Motorola

Related People

Tim Spets: AUTHOR

Abstract

In a connection oriented LLC (Logical Link Control OS1 layer 2 data link layer) using a Selective Block Reject retransmission scheme, the peer notifies the sender not only if a datagram has been received but what portions have been received. It uses sequence numbers to distinguish one datagram from another. The acknowledgment information is critical in reducing needless re-trans- missions. The MAC (Media Access Control) layer is responsible for the actual addressing and selection of transmission path. With this invention the MAC will also send the LLC a Notification of end of transmission for each transmission received via the RF interface.

This text was extracted from a PDF file.
At least one non-text object (such as an image or picture) has been suppressed.
This is the abbreviated version, containing approximately 50% of the total text.

Page 1 of 2

0 M

MOTOROLA Technical Developments

INTEGRATING A MAC "NOTIFICATION OF END OF TRANSMISSION" WITH A RELIABLE LLC DATA LINK LAYER THAT TRANSMITS MULTIPLE DATAGRAMS

IN A SINGLE TRANSMISSION IN A PACKET DATA SYSTEM

by Tim Spets

  In a connection oriented LLC (Logical Link Control OS1 layer 2 data link layer) using a Selective Block Reject retransmission scheme, the peer notifies the sender not only if a datagram has been received but what portions have been received. It uses sequence numbers to distinguish one datagram from another. The acknowledgment information is critical in reducing needless re-trans- missions. The MAC (Media Access Control) layer is responsible for the actual addressing and selection of transmission path. With this invention the MAC will also send the LLC a Notification of end of transmission for each transmission received via the RF interface.

  To describe the benefit of this publication the following describes three LLC procedures that are effected by the integration of the MAC's Notification to LLC of end of transmission.

TRANSMITTING DATAGRAMS

  When the sender of the LLC protocol receives the "channel available" it will transmit multiple datagrams at the same time, it will select only one retransmission timer for all of them and associate them together.

SEND ACKNOWLEDGMENT

  When the peer receives the datagrams, the MAC is notified of a "transmission reservation length" from the peer which notifies it of how many bytes are being transmitted. The MAC layer knows definitively when a transmission reservation on the channel is complete. This indication is sent to the

LLC layer as an indication (Notification to LLC of end of transmission) that all of the datagrams sent in the single transmission have been received (partial, full or lost) and the LLC will now be able to build a Multiple Acknowledgment Packet (contains status for all received datagrams be it either full or partial). This insures that no datagrams are acknowledged until the entire transmission has been completed. This is important due to the peer Transmitter will turn off the re-transmission timer for ALL of the datagrams when an acknowledgment is received by and ONE of them.

RECEIVE ACKNOWLEDGMENT PROCEDURE...