Trying out GameFuel
D-Link's demo at CES attempted to show the benefit of GameFuel by running a long FTP upload while simultaneously engaging in gameplay. I'm not a gamer, plus I wanted something more quantitative than trying to figure out whether GameFuel was helping me to kill more bad guys.
So I kept the idea of running a simultaneous FTP upload, but instead ran simulated VoIP calls using TestYourVoIP.com's TestMyVoIP Java application. I ran three sets of tests: the VoIP test alone; the VoIP test with FTP but GameFuel disabled; and VoIP test with FTP and GameFuel with Automatic Classification turned on. Table 1 summarizes the results
| VoIP only | VoIP + FTP (w/o GameFuel) | VoIP + FTP (w/ GameFuel Auto Classification) | |
| Round-Trip Latency | 122mS | 406 ms | 260 ms |
| Packet Discards | 0.1% | 1.5% | 0.4% |
| Packet Loss | 0.1% | 0.0% | 0.1% |
| Loss Periods | Min: 20 ms Avg: 20 ms Max: 20 ms Random Loss | Min: 100 ms Avg: 100 ms Max: 120 ms Burst Loss | Min: 20 ms Avg: 20 ms Max: 40 ms Random Loss |
| Jitter | Min: 0 ms Avg: 6 ms Max: 26 ms | Min: 0 ms Avg: 23 ms Max: 170 ms | Min: 1 ms Avg: 15 ms Max: 50 ms |
| Table 1: GameFuel Test Results | |||
The biggest differences are in Round-Trip Latency, Packet Discards and Jitter, which I've highlighted in yellow. The results show that GameFuel doesn't completely eliminate the effects from FTP's simultaneous use, but in this test most significantly reduced discarded packets and jitter - both of which can ruin a VoIP call.
Figure 12: GameFuel Auto Classification in action
(click image to enlarge)
By the way, I found that the 4300's Active Sessions status page is a great tool to see what's passing through your router. It also provides an insight into the way that GameFuel is prioritizing your traffic. You just need to get used to looking at the port numbers in the External column and be prepared to do some IP address lookups to see the whole story. Figure 12 is a snapshot of the Active Sessions page taken while a simultaneous FTP plus TestYourVoIP test was running with GameFuel / Auto Classification engaged.
The second line down shows that the FTP session (Port 21) is assigned a priority of 150 (the range is 1 to 255), while the VoIP UDP sessions (ports 5060, 50496 and 50497) were assigned priorities of 128, 149 and 143. You can see most other sessions have priorities assigned in a surprisingly small range, except for one at the lowest value of 255.