Latency of WiFi router

Question

My current gaming desktop is connected to router via few meters of class 5 UTP. But I have to move it to another room, and I'm reluctant to drill holes in the wall to get cables trough. Currently I have simple SOHO WiFi G router with only internal antenna. Quick test with laptop showed some 10ms extra latency, but I'm not sure it that's the best WiFi can do. I have few doubts:

• What order of latency would WiFi add in ideal situation (as compared with 100Mb Ethernet)?
• How much does it depend on quality of WiFi router?
• How much does it depend on version of WiFi used (G vs N)?
• How much better do "gaming" routers perform?
• How much better MIMO with 3 antennas will perform?

Answer 1

What order of latency will using WiFi instead of 100Mb Ethernet add in ideal situation?

Wireless is slower, can have security problems and anything can cause problems from cordless phones, microwaves, energy saving lights etc. There are limited isolated channels (only 3) and if other people are using it, you can have big interference and increased latency, lower speeds, or just plain old drop outs.

How much does it depend on quality of WiFi router?

Very much so, but quality is subjective. I am a huge fan of cheap Chinese/far-east manufacturerd routers such as TP-Link, whilst an unknown brand and thought of as dirt cheap, the firmware is completely unlocked and allows you to have many ssids, control the aerial power and many features that you would have to unlock/flash another router (such as DD-WRT) to provide.

How much does it depend on version of WiFi used (G vs N)?

Well, always, newer the better.

How much better do "gaming" routers perform?

Refer back to the one about quality, typically a company would brand their routers in the order of: Commercial or bulk / gaming or high end / business / enterprise... typically gaming ones are just high end ones with a few flashing lights. That being said, going to the other question again, look at the actual specifications rather than brand.

Answer 2

10ms seems high. Regardless of the a/b/g/n flavor, latency for typical small once-per-second pings on a reasonably clean channel should be less than 4ms. It can be greater than that from time to time if you're so far away from your AP that your client is periodically going off-channel to scan to find another AP to roam to. It can also be a bit worse from time to time if your signal-to-noise ratio changes and your devices have to find new data rates to use.

That said, if you're doing twitch gaming (first-person shooters and the like) over the Internet, you always want the max bandwidth and reliability and minimum latency you can get, and wireless will never compare to a wired connection for those criteria.

It's also bad networking engineering practice to burn wireless bandwidth for stationary devices. Most people are happier in the long run if they spend the money on proper wiring for their stationary devices and save their wireless bandwidth for their mobile devices.

Update: You should look into getting a "gaming" router anyway. What typically distinguishes a gaming router from other consumer routers is not the quality of the wireless interface, but the speed of the processor. Gaming routers have enough processor headroom that they can perform NAT more quickly, with less effect on bandwidth and latency. So that's something your gaming sessions could benefit from even if you're wired into a LAN port. I second Wil's recommendation that you look at specs. If they don't bother to measure and publish a spec number you care about, it means they don't care about it or they care about it but know that product is mediocre with regard to that metric.

Answer 3

I tried using my 3COM WLAN router now, and latency added seems to be below 1ms. Try pinging a stable site with and without using your WLAN router. With my router I get 4ms ping time to a server located around 10 km away. Without the WLAN roter, I also get 4ms ping time to the same server.