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My ISP provides a 50M(bps) download line for me. But my both laptops only have 802.11g Wi-Fi network card, so my Asus RT-N12 router (firmware upgraded to DD-WRT) has been configured to 802.11g AP with max download 20M. I am not happy with this since the other 30MB is not being used.

I was wondering if I set up 2 SSID on Asus router, and have both SSID uses its own 20M bandwidth? That way I can utilize 40M. Is this possible?

EDIT: It's my router with almost default settings. These are some facts:
- testing speed from several sites, and all got similar results.
- wire connection has 50M download speed, where wireless connection has 20M
- wireless security mode is "WPA2 personal mixed". (not sure if this effects the throughput)
- no QoS
- wireless channel bandwidth = 20MHz (default, unchanged)
- MTU = manual 1492 (default, unchanged)


One of the laptop is Lenovo T420. My NIC is showing "1x1 11b/g/n Wireless LAN PCI Express Half Mini Card Adapter" in device manager. In the property > advance tab, these are properties I saw:

  • 802.11d = disable
  • Beacon Interval = 100
  • Preamble Mode = Short & long
  • Roaming Sensitivity Level = Low
  • TX Power Level = Auto
  • Wiress Mode = IEEE 802.11b/g/n

When setting my AP to 802.11n only mode, my T420 wouldn't connect to the AP. It only connects when AP is set to 802.11g/n mixed mode or below that mode. How could I get 802.11n mode working? Am I having wrong driver?

share|improve this question
Who set up your router with DD-WRT? Who put the bandwidth limit of 20mb/s on it? in the 35 pages of post… there about that router, not one person mentions a bandwidth cap. If you can't connect wirelessly to the router at any speed greater than 20mb/s (which is less than HALF of 802.11g speeds) then your issue isn't a speed cap. – Bon Gart Jun 14 '12 at 14:24
and to put a finer point on it, more than one individual in that forum thread I gave you a link to points out that they can connect to the router via wireless at 150mb/s. – Bon Gart Jun 14 '12 at 15:17
@Bon Gart: A node with an 802.11g NIC can never connect at 150 Mpbs, no matter how you configure the access point. – Ben Voigt Jun 14 '12 at 15:51
@BenVoigt I fail to see your point. I never mentioned anything about someone using a G (54mb/s) or Super G (108mb/s) Nic getting 150mb/s to that router. I DID mention that people have reported being able to connect and get 150mb/s, which would contradict the OP's statement that the router is capped at 20mb/s just by having DD-WRT installed. – Bon Gart Jun 14 '12 at 15:53
Some other users (including myself, but not everyone) are experiencing throughput problems with this Asus RT-N12 router and DD-WRT. – drs Dec 28 '13 at 4:02

Multiple SSIDs will not solve this. The reason is that there is still only one radio.

One client connected at 22 Mbps to a 300 Mpbs-capable access point does not utilize just 7% of the available capacity. It is talking slowly, taking as much time to transfer 22 MB as an N-turbo client would need for transferring 300 MB, but it is still talking the whole time, using up the whole channel.

This is like asking whether you can get between two cities faster on a highway where the speed limit is 45 mph by making half the trucks a different color.

However, 802.11g is capable of speaking faster than that, up to 54 Mbps. Try unlocking all speeds and see if your throughput goes up. (This uses a larger signal constellation, and needs higher signal-to-noise ratio, so if you have marginal signal it won't help. But with strong signal your usable bandwidth will double.)

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In addition Windows would only allow him to connect to a single access point since he doesn't have two wireless devices to bridge two connections ( event this would not INCREASE ) his bandwidth. – Ramhound Jun 14 '12 at 16:01
@Ramhound: Two different Windows laptops can connect to two different SSIDs. Or am I misreading the question? – Ben Voigt Jun 14 '12 at 16:08

Multiple SSIDs will not solve this. Using N wireless cards or a wired connection can help.

share|improve this answer
it is an N router, and no one else who posts about that exact model router running DD-WRT reports about a bandwidth cap. In fact, the speeds that are reported are just fine. I believe his issue is one of mis-configuration... but then again, I have to wonder why he even put DD-WRT on the router in the first place – Bon Gart Jun 14 '12 at 15:19
fixed my comment. I bet there is no cap. – uSlackr Jun 14 '12 at 15:54
either no cap... or the router isn't his and someone set up QoS to keep him from being able to use all the bandwidth, or he is basing his belief that there is a cap on download speeds he is getting from a specific site. – Bon Gart Jun 14 '12 at 15:56

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