D-Link Wireless N Router and Adapters

Reviews: Networking

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Richard Poelling
Brian
D-Link
Mar. 22, 2007

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Testing

This is always the disappointing section for wireless testing. I stopped hoping for "wired" speeds long ago, and I doubt this will be any different. As I have seen in the past, advertised speeds do not necessarily mean real world speeds. For testing purposes, the speeds listed here are for the laptop card which would get the most mobile functionality. As a comparison, I used the built-in wireless G of the laptop as a baseline.

When connected to the access point, the adapter will display 300 Mbit as the connection speed. I probably don't have to tell you that the speeds I got are not even close. To determine what kinds of speeds I was getting from my setup, I utilized a program called Qcheck that is distributed by IXIA. This free utility allows for the determination of response time (latency) and throughput. To do this, the program has to be installed on all machines used in the test. The program runs as a service called Endpoint in the background. It enables you to test from either direction on any two machines that it is installed on, (i.e. A to B, or B to A). All throughput testing was done with a 1,000 KB setting in Qcheck. The scores are an average of 20 runs, 10 runs from the server to wireless connection and another from the wireless connection to server.

As is apparent on the graphs, the speed does not approach 200Mbps. On a good day I can get 50, which is not too shabby for a wireless connection. I will say that the observed versus the measured speeds are starting to deviate far more than they used to. Either way, a good 802.11N connection will give you the required speed of >25 Mbps to stream HD media. This is honestly the most anyone could really hope for, and it is one of the main reasons the 802.11n specification is being used in so many media players, even if it is only a "draft" specification. I will also say that for general tasks such as file transfers I found the 802.11n to be far more transparent with a lack of lag I will sometimes get with 802.11g.

Qcheck

Throughput

Wireless N

Wireless G

42.58

23.85

Mbps

Although this does not technically fall under a performance test, I decided to see just what happens when the 802.11n connection gets heavily used. Using my trusty Wi-Spy, I was able to monitor the spectrum as the connection becomes saturated. To accomplish this, I transferred a large file from one machine to the next. I used both a 802.11g connection and then the 802.11n connection. Using the Channelyzer software and knowing the time of transfer, I was also able to determine the transfer speed by an alternate method. The file I transferred was 366,407,680 bytes. This resulted in a throughput for 802.11g of 1.37 MBps and for 802.11n of 2.62 MBps. In the 802.11n image you can also clearly see the secondary channel come to life which is a big reason that its speeds are so much higher.

Wireless 802.11g Transfer

Wireless 802.11n Transfer

Conclusion

The specification for 802.11n is without a doubt better than its predecessors, b and g. The dilemma is just how much better. Since 802.11n is still a "draft" specification, we can not definitively put our stamp of approval on it. Interoperability issues are probably going to be the first items which will cause problems, especially between vendors. There are hopes that the "draft" will become an "approved" standard this year. We can only hope. There are already manufacturers releasing 802.11n products, certified or not, the industry is and will continue to move forward.

Even though the standard isn't final, I still liked this product. My likes are less about the standard and more towards the basic functionality. Having a wireless N card is mostly useless, since airports, hotels and most hotspots have standardized on the 802.11g protocol. I am sure over time that will change, and I will say that connecting using 802.11g was no problem. What really makes this product was by far the router. The well designed administrative controls and the ability to dump syslog information made it a very nice addition to my network. Even if you only want to use 802.11g, I think the D-Link DI-635 would make an excellent choice both for now and in the future, especially if they fix that little jumbo frames snafu!

Pros

802.11n speed
Ability to capture syslog data
excellent port forwarding setups

Cons

802.11n is still "Draft"
No Gigabit switch
Unable to access administrator console using Jumbo frames >4000 bytes

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Page 1: Introduction & First Looks
Page 2: Setup & Features
Page 3: Testing & Conclusion

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