Method and apparatus for generating a plurality of CRC digits for data packets having different prescribed network protocols using one CRC generator

• US 6,704,364 B1
• Filed: 03/28/2000
• Issued: 03/09/2004
• Est. Priority Date: 12/29/1999
• Status: Expired due to Fees

• Current Assignee: GlobalFoundries, Inc.
• Original Assignee: Advanced Micro Devices, Inc.
• Inventors: Dwork, Jeffrey, Lim, Alvin Swee Hock
• Primary Examiner(s): Chin, Stephen
• Assistant Examiner(s): ODOM, CURTIS B
• Application Number:
  US09/536,606
• Time in Patent Office: 1,442 Days
• Field of Search: 375/211, 375/257, 375/240.01, 375/222, 375/260, 370/419, 370/293, 370/362, 370/335, 370/255, 370/412, 370/401, 370/392, 714/758
• US Class Current: 375/257
• CPC Class Codes: H04L 1/0041 Arrangements at the transmitter end
• CPC Class Codes: H04L 1/0061 Error detection codes
• CPC Class Codes: H04L 1/0065 Serial concatenated codes

Abstract

A network interface that can converts frame data into a data packet which is sent from one local area network to another local area network in which the two local area networks operate using different prescribed network protocols. The network interface receives frame data from a transmit buffer and converts the frame data into a first data packet having a first prescribed network protocol and where the data packet includes first CRC digits. Logic converts the first data packet into a converted data packet having a second prescribed network protocol, which is different than the first prescribed network protocol. The converted data packet also includes second CRC digits which were generated based on the converted data packet at well as being generated by the same CRC generator that generated the first CRC digits.

Claims

1. A network interface comprising:

a media access controller configured for outputting a data packet having a first prescribed network protocol based on a received frame data, where the data packet includes a first cyclic redundancy check character, the media access controller comprising a cyclic redundancy check generator configured for generating the first cyclic redundancy check character based on the received frame data;

logic configured for converting the data packet in the first prescribed network protocol into a converted data packet having a second prescribed network protocol and a second cyclic redundancy check character generated by the cyclic redundancy check generator, the logic replacing the first cyclic redundancy check character with the second cyclic redundancy character; and

a media independent interface configured for receiving the converted data packet from the logic and transmitting the converted data packet.

2. The network interface of claim 1, further comprising a backbone interface configured for transmitting the converted data packet from the media independent interface to another local area network via a backbone link.

3. The network interface of claim 1, wherein the first prescribed network protocol is compliant with IEEE 802.3 network protocol.

4. The network interface of claim 1, wherein the media access controller further comprises a selector circuit configured for supplying coefficients for a prescribed network protocol to the cyclic redundancy check generator for generating the cyclic redundancy check digits.

5. A method for generating a cyclic redundancy check character in a media access controller, comprising:

receiving a data packet, having a first prescribed network protocol and having a first cyclic redundancy check character, by logic from a media access controller, where a cyclic redundancy check generator in the media access controller is configured for generating the first cyclic redundancy check character based on received frame data;

converting the data packet in the first prescribed network protocol into a second prescribed network protocol by the logic;

providing information relating to the converted data packet to the cyclic redundancy check generator;

generating a second cyclic redundancy check character in response to the information relating to the converted data packet;

modifying the converted data packet by replacing the first cyclic redundancy check character with the second cyclic redundancy check character; and

transmitting the modified converted data packet having the second cyclic redundancy check character via a media independent interface.

6. The method of claim 5, further comprising transmitting the converted data packet from the media independent interface onto a backbone to another local area network via a backbone link.

7. The method of claim 5, wherein providing information relating to the converted data packet to the cyclic redundancy check generator further comprises supplying coefficients for the second prescribed network protocol to the cyclic redundancy check generator.