Dynamic inter packet gap generation system and method

• US 8,160,089 B1
• Filed: 11/04/2003
• Issued: 04/17/2012
• Est. Priority Date: 11/04/2003
• Status: Active Grant

• Current Assignee: Advanced Micro Devices, Inc.
• Original Assignee: Advanced Micro Devices, Inc.
• Inventors: Padiyar, Prasad P., Karighattam, Kishore, Vasudeva, Harish
• Primary Examiner(s): Pham, Chi
• Assistant Examiner(s): ADHAMI, MOHAMMAD SAJID
• Application Number:
  US10/701,092
• Time in Patent Office: 3,087 Days
• Field of Search: None
• US Class Current: 370/445
• CPC Class Codes: H04L 12/413 with random access, e.g. carrier-sense multiple-access with collision detection [CSMA-CD]

Abstract

The present invention facilitates network throughput by dynamically generating IPG values, which are employed when recovering from network collisions. Testing a number of IPG values and tracking collisions that occur as a result for each value generate the IPG value. The IPG value that yielded the lowest collisions is then programmed as the IPG value for a network device. This value remains in use by the network device for a stable state time period. After this period, another dynamically generated IPG value is obtained.

Claims

1. A network station comprising:

a network device having a collision counter that tracks collisions and an inter packet gap unit that is programmable; and

a dynamic IPG determiner that obtains collision counts from the collision counter, dynamically generates an IPG value that is a function of the collision counts and programmable parameters, wherein the programmable parameters include;

a range of IPG values;

a step value;

a convergence time; and

a stable state time, and

programs the inter packet gap unit with the dynamically generated IPG value.

2. The station of claim 1, wherein the dynamic IPG determiner periodically generates the IPG value after a steady state time period.

3. The station of claim 2, wherein the steady state time period is 1 second.

4. The station of claim 1, wherein the dynamic IPG determiner generates the IPG value by testing a plurality of IPG values and evaluating a number of collisions for each of the IPG values.

5. The station of claim 4, wherein the range of IPG values is from 96 bit times to 272 bit times.

6. The station of claim 4, further comprising a storage unit that maintains collision counts associated with tested IPG values.

7. The station of claim 6, wherein the dynamic IPG determiner and the storage unit are components of a device driver.

8. The station of claim 1, wherein the network device is operable to transmit and receive data at 100 Mbps in half duplex mode.

9. A method of dynamically generating an IPG value for a network device comprising:

setting one or more programmable parameters, wherein the programmable parameters include;

a range of IPG values;

a step value;

a convergence time; and

a stable state time;

dynamically determining an IPG value from the range of IPG values according to tracked collisions and the programmable parameters;

programming the network device with the determined IPG value.

10. The method of claim 9, wherein dynamically determining an IPG value from the range of IPG values comprises:

testing one or more IPG values of the range of IPG values;

obtaining respective collision counts for the one or more tested IPG values;

selecting the determined IPG value as being the value of the one or more tested IPG values that yielded a lowest collision count.

11. The method of claim 10, wherein testing each of the one or more IPG values comprises:

programming an IPG current value to a network device;

obtaining a current collision count over a selected period of time;

setting an IPG modified value to the IPG current value on the current collision count being less than that associated with the IPG modified value; and

incrementing the IPG current value by a step value.

12. The method of claim 11, wherein the IPG modified value is the determined IPG value.

13. The method of claim 11, wherein the current collision count is obtained from the network device.

14. The method of claim 11, wherein the IPG current value is initially 96 bit times.

15. The method of claim 11, wherein the step value is 1 bit time.

16. The method of claim 11, wherein the method is performed after a stable state period.

17. The method of claim 16, wherein the stable state period is 60 seconds.