Why I love this router.

[ChrisR]

I have a 60/6 connection. Router is extremely stable. To connect to my office phone, I use Cisco VPN, Cisco IP Communicator and a bluetooth headset. With previous routers, I got at least 4 disconnections a day, with bluetooth turned on for my headset it disconnected each minute (and I had to use wired connection. It happened with Dell and Lenovo laptops with different wireless cards).

With my new RT-N66U, using since a few months, I face a disconnect once in the 2 weeks (or less) and even can use my bluetooth headset with wireless connection (2.4) without any problem!!

[SoCalReviews]

Originally Posted by got_milk

Unfortunately with a 16/1 connection and 3-4 consistently heavy users of that bandwidth I simply cannot get by with having QoS off. Low-latency applications can be miserable to use when the connection's bogged down.

I also came from a WNDR3700v1 with OpenWrt and noticed an improvement with the RT-N66U overall with QoS on. I don't think it's having QoS off, I think it's how much better the router is.

Of course the main reason for QoS settings on a gigabit router is to overcome the internet WAN connection bandwidth bottleneck for high priority services (VoIP, video teleconferencing, critical applications, etc.). As long as your LAN side is running up to gigabit speeds and your router hardware can handle the traffic then the WAN side is where the problems with QoS happen. If you have adequate internet bandwidth with low latency on the WAN side then QoS shouldn't be needed. Forcing the router to prioritize and analyze packets when there is no internet bandwidth bottleneck to begin with only increases it's processor workload and more than likely will decrease overall performance to some measurable degree.

Another consideration is that the BCM chipset in the RT-N66U already handles the WAN to LAN traffic prioritization in the hardware along with integrated default optimized settings in the OpenWRT firmware. If the router has to expend more processing power analyzing and prioritizing the packets based on custom settings in the firmware as opposed to utilizing optimized default settings for the hardware then it is logical to assume there will be performance penalty. It may not be as noticeable with the RT-N66U since it has high quality hardware optimized for performance.

It may be that other routers experience more bottlenecks and problems using QoS due to lower performance hardware and inadequately optimized firmware. I know that I had to use QoS settings on my 100/5 cable internet connection with the WNDR-3700v2 or major problems would occur with my latency sensitive applications (VoIP, online gaming, etc.). When I replaced it with the RT-N66U not only did I not have to use QoS but with QoS off all my latency sensitive applications seemed to run better with QoS off on the RT-N66U than they ever did with QoS turned on in the WNDR-3700v2 settings. I can have multiple video steams, HD video streams, multiple wireless devices connected and large file downloads running through two other gigabit routers (using double NAT) and several gigabit switches...all happening simultaneously but at the same time I can still send regular fax over my VoIP system with no problems (when it used to not be possible) and I experience little if any noticeable lag during latency sensitive online gaming (when the lag during online gaming made it almost unplayable before).

[got_milk]

Originally Posted by SoCalReviews

Another consideration is that the BCM chipset in the RT-N66U already handles the WAN to LAN traffic prioritization in the hardware along with integrated default optimized settings in the OpenWRT firmware.

Source? The closest thing I can think of that you're referring to is cut-through forwarding, but that's not prioritization. As far as I know, without QoS, packets are received and routed in the order which they are received in the buffer, no prioritizing.

Originally Posted by SoCalReviews

I know that I had to use QoS settings on my 100/5 cable internet connection

Your connection and use case simply doesn't warrant QoS then. QoS is only really meant to help when the WAN link is saturated entirely and services are being affected. On my 16/1 connection, I simply cannot get away with that kind of usage while maintaining stable connections throughout.

[SoCalReviews]

Originally Posted by got_milk

Source? The closest thing I can think of that you're referring to is cut-through forwarding, but that's not prioritization. As far as I know, without QoS, packets are received and routed in the order which they are received in the buffer, no prioritizing.

Your connection and use case simply doesn't warrant QoS then. QoS is only really meant to help when the WAN link is saturated entirely and services are being affected. On my 16/1 connection, I simply cannot get away with that kind of usage while maintaining stable connections throughout.

SNB review of the RT-N66U

http://www.smallnetbuilder.com/wirel...outer-reviewed

Most of the newer routers like the RT-N66U use the newer Broadcom chip sets with chips such as the Smart GbE Switch BCM53115.

"The BCM53115 architecture is the optimal solution for consumer switching needs with its support for high-performance line rate capabilities and ability to identify and prioritize different data packet types within the switch while simultaneously assigning voice packets a higher priority for outbound communications."

http://www.broadcom.com/products/Swi...iness/BCM53115

I am not sure how the features of these newer BCM chips are utilized by the RT-N66U router but I heard Asus claims that they optimized the firmware for maximum performance of the router's hardware right out of the box. Unless you absolutely need to change the settings for your network then the default settings are suppose to offer the best performance. With the exception of changes to the wireless radio settings using fixed channels I run the default settings and it's blazing fast.

I am not doubting that you may need QoS but just to make certain and not to just go with assumptions... Have you tried turning QoS to the default of "off" to see how it impacts performance of latency sensitive applications on your network?

[kuby8388]

it is a fast router when it's working perfectly as it's capable off....

although I think that's only for 75% of the owners.

[got_milk]

Originally Posted by SoCalReviews

SNB review of the RT-N66U

http://www.smallnetbuilder.com/wirel...outer-reviewed

Most of the newer routers like the RT-N66U use the newer Broadcom chip sets with chips such as the Smart GbE Switch BCM53115.

"The BCM53115 architecture is the optimal solution for consumer switching needs with its support for high-performance line rate capabilities and ability to identify and prioritize different data packet types within the switch while simultaneously assigning voice packets a higher priority for outbound communications."

http://www.broadcom.com/products/Swi...iness/BCM53115

What about connections over wireless? They wouldn't go through the switch, therefore wouldn't be prioritized.

Originally Posted by SoCalReviews

Have you tried turning QoS to the default of "off" to see how it impacts performance of latency sensitive applications on your network?

ICMP response time to google.ca during upload bandwidth saturation (QoS off):



ICMP response time to google.ca during upload bandwidth saturation (QoS on, set to 90% of average upload bandwidth):



ICMP response time to google.ca during upload bandwidth saturation (QoS on, set to 85% of lowest measured upload bandwidth (as per Toastman's QoS guide)):

[SoCalReviews]

Originally Posted by got_milk

What about connections over wireless? They wouldn't go through the switch, therefore wouldn't be prioritized.

I am not a designer of integrated gigabit switches so I couldn't explain to you exactly how it works. The link I provided before does say that the 5 port switch IMP for "glueless connection to a CPU or WLAN". The WLAN traffic has to pass through the same gigabit switch to route to the LAN or the WAN. I can't imagine a BCM53115 gigabit switch chip in the Asus router configured not to manage the connection to the CPU or WLAN nor would it make sense for the chip specifically to be designed and marketed to handle packet prioritization but not have that feature actively enabled for a device using a set of Broadcom integrated chips designed for use in consumer routers. I don't claim to be an expert on chipsets or router design so if you can explain how it works better than Broadcom does then I'm open learning something new.

Smart GbE Switch

Features

Highly integrated, 65-nanometer (nm) process, non-blocking 5-port 10/100/1000 switch silicon that integrates five 10/100/1000 PHYs and two fully integrated, GMII/RGMII/MII interfaces Inband Management Ports (IMP) for glueless connection to a CPU or WLAN.

http://www.broadcom.com/products/Swi...iness/BCM53115


Ultimately its your choice how you want to configure your RT-N66U with QoS on or off. You provided upload data in your above post. It isn't difficult to saturate 1Mbps of upstream internet bandwidth. If upload is your critical bottleneck it might work better on your network with QoS on and custom rule settings. I know that many router manufacturers including Asus warn about performance degradation when enabling certain settings and customizations. Customized settings that may be required for one design of router don't always work as well with another. I also know from experience that for my network QoS off on the RT-N66U equals the lowest latency and highest throughput with my network under load than any other previous router I have ever owned.

I do have a unique setup in my home. I have both a 12/1 DSL connection and a 100/5 cable internet connection with a RT-N66U on both connections (two separate Asus routers) to test with. With the exception of the radio settings they are set up with the rest of the exact same settings with QoS turned off. I have had up to thirty devices connected via Ethernet and wireless at the same time when testing the routers. I almost never experience latency problems on the cable connection. It does depend on the traffic load but under moderate usage I seldom experience latency issues on the DSL connection.