Multiplex communications – Communication techniques for information carried in plural... – Assembly or disassembly of messages having address headers
Reexamination Certificate
1999-12-17
2004-05-25
Ton, Dang (Department: 2664)
Multiplex communications
Communication techniques for information carried in plural...
Assembly or disassembly of messages having address headers
C370S412000, C370S395710
Reexamination Certificate
active
06741611
ABSTRACT:
TECHNICAL FIELD OF THE INVENTION
This invention relates generally to data communications and more particularly to data communications in a shared media access environment.
BACKGROUND OF THE INVENTION
This disclosure is related to a co-pending European Patent Application filed simultaneously herewith by the applicant and entitled “IN ORDER BROADCAST MANAGEMENT (IOBMAN) SCHEME”, which is herein incorporated by reference in it's entirety.
In a communications device, such as an Ethernet switch, frames of data are received through ports on the device and buffered while addressing logic in the communications device processes addressing information associated with the frame to determine its destination. In general, the frames of data are stored in 64 byte blocks of memory
102
such as shown in
FIG. 1
, each block
102
having an associated 4 byte pointer
104
which points to the next 64 byte block of data
102
which comprises the frame. As defined in the IEEE 802.1Q standard for virtual local area networks (VLANs), the data portion of a received frame can be from 528 to 1577 bytes long.
As such, this memory management scheme is simple but not very effective when the frames of received data do not align on 64 byte margins. For example, if a frame of received data is 65 bytes long, it takes as much time and as much memory as it takes to store to and retrieve a frame of received data that is 128 bytes in length. Furthermore, no special consideration is made for broadcast frames, i.e., frames addressed to multiple destination addresses.
What is needed is a memory management scheme with improved efficiency in storing and retrieving variable length frames of data.
SUMMARY OF THE INVENTION
The present invention is a method and system for managing memory in a communication device which operates in a shared access media environment. In one aspect of the invention, each incoming frame of data is packed and stored in blocks of no more than a predetermined block size, each block have an associated tag of control data and an associated pointer stored in a pointer memory for locating the block of data.
In another aspect of the invention, the incoming frames of data are of varying size.
REFERENCES:
patent: 5619497 (1997-04-01), Gallagher et al.
patent: 5633865 (1997-05-01), Short
patent: 5742760 (1998-04-01), Picazo, Jr. et al.
patent: 5778414 (1998-07-01), Winter et al.
patent: 6233244 (2001-05-01), Runaldue et al.
patent: 6295094 (2001-09-01), Cuccia
Robertson Iain
Szczepanek Andre
Brady III Wade James
Telecky , Jr. Frederick J.
Texas Instruments Incorporated
Ton Dang
Tran Phuc
LandOfFree
Packet memory management (PACMAN) scheme does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Packet memory management (PACMAN) scheme, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Packet memory management (PACMAN) scheme will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-3186715