Simulate high speed network connection

I have cre开发者_C百科ated a bandwidth meter application to measure total Internet traffic. I need to test the application with relatively high data transfer rates, such as 4 Mbps. I have a slow Internet connection, so I need a simulator to test my application to see the behavior with high throughput rates.

As an option, you can run some HTTP server in one virtual machine with NAT'ed network adapter and test your bandwidth meter against it from the host system or a similar VM.

There are commercial packet generators that do this, and also a few freely available ones like PackETH and Bit-Twist.

There are also other creative solutions. For example, do the packets need to be IP packets for your purpose? If not, you could always get a "dumb" switch or hub (no spanning-tree or other loop protection) and plug a crossover cable into it. (or a straight-through Ethernet cable would work if the switch supports Auto-MDIX) The idea would be that with a loop in your network, the hub/switch will flood the network to 100% for you since it will continually re-forward the same packets.

If you try this, be sure yours is the only computer on the network, since this technique will effectively render it useless. ;-)

You could always send some IP broadcast packets to "seed" the loop. Otherwise, the first thing I think you'd likely see is broadcast ARP packets, which won't help if you're measuring layer 3 traffic only.

Lastly, (and especially if this sounds like too much trouble) I recommend you read up on dependency injection and refactor your code so you can test it without the need for a high-speed interface. Of course, you'll still need to test your code in a real high-speed environment, but doing this will give you much more confidence in your code.