High Precision Packet Generation in Software Using a Hardware Time Stamp Counter

• US 20120033562A1
• Filed: 08/04/2010
• Published: 02/09/2012
• Est. Priority Date: 08/04/2010
• Status: Active Grant

• Current Assignee: Keysight Technologies Singapore Sales Pte Ltd (Keysight Technologies, Inc.)
• Original Assignee: Keysight Technologies Singapore Sales Pte Ltd (Keysight Technologies, Inc.)
• Inventors: Stanciu, Adrian, Gruber, Matei
• Granted Patent: US 9,985,864 B2
• Time in Patent Office: Days
• US Class Current: 370/252
• CPC Class Codes: H04L 43/08 Monitoring or testing based on specific metrics, e.g. QoS, energy consumption or environmental parameters
• CPC Class Codes: H04L 43/106 using time related information in packets, e.g. by adding timestamps
• CPC Class Codes: H04L 43/12 Network monitoring probes
• CPC Class Codes: H04L 43/50 Testing arrangements

Abstract

There is disclosed a system and method for high precision packet generation in software using a hardware time stamp counter. The method may include receiving user selection to create a network test and receiving test information from the user, the test information including a packet transmission rate. A packet transmission interval may be calculated based on the packet transmission rate. The network test is executed. Packets are transmitted at the packet transmission rate, including checking a hardware counter to learn if the packet transmission interval has elapsed and, when the packet transmission interval has elapsed, sending the packet over a network. The method may be performed by a network testing system or computing device.

Claims

1. A network testing system having at least one network card, the network card including a processor, a memory and a network communications unit, the network testing system coupled with a network, the network testing system having instructions stored thereon which when executed cause the network testing system to perform operations comprising:

receiving user selection to create a network test

receiving test information from the user, the test information including a packet transmission rate and packet creation information

calculating a packet transmission interval based on the packet transmission rate

receiving user selection to execute the network test

transmitting packets specified in the network test over the network at the packet transmission rate, including

preparing a packet including at least a payload and a header according to the packet creation information

checking a hardware counter to learn if the packet transmission interval has elapsed

when the packet transmission interval has elapsed, sending the packet over the network.

2. The network testing system of claim 1 wherein the hardware counter is a time stamp counter (TSC) register of the processor included in the network card.

3. The network testing system of claim 1 wherein the checking the hardware counter comprises making a call to a routine in a kernel of an operating system executing on the network card.

4. A computing device having at least one virtual machine executing network testing software, the computing device including a processor, a memory and a network communications unit, the computing device coupled with a network, the network testing software comprising instructions which when executed cause the computing device to perform operations comprising:

receiving user selection to create a network test

receiving test information from the user, the test information including a packet transmission rate and packet creation information

calculating a packet transmission interval based on the packet transmission rate

receiving user selection to execute the network test

transmitting packets specified in the network test over the network at the packet transmission rate, including

preparing a packet including at least a payload and a header according to the packet creation information

checking a hardware counter to learn if the packet transmission interval has elapsed

when the packet transmission interval has elapsed, sending the packet over the network.

5. The computing device of claim 4 wherein the hardware counter is a time stamp counter (TSC) register of the processor.

6. The computing device of claim 4 wherein the checking the hardware counter comprises making a call to a routine in a kernel of an operating system executing on the computing device.

7. A machine readable medium having instructions stored thereon which when executed cause a computing device to perform operations comprising:

receiving user selection to create a network test

receiving test information from the user, the test information including a packet transmission rate and packet creation information

calculating a packet transmission interval based on the packet transmission rate

receiving user selection to execute the network test

transmitting packets specified in the network test over a network at the packet transmission rate, including

preparing a packet including at least a payload and a header according to the packet creation information

checking a hardware counter to learn if the packet transmission interval has elapsed

when the packet transmission interval has elapsed, sending the packet over the network.

8. The machine readable medium of claim 7 wherein the hardware counter is a time stamp counter (TSC) register of a processor included in the computing device.

9. The machine readable medium of claim 7 wherein the checking the hardware counter comprises making a call to a routine in a kernel of an operating system executing on the computing device.