Asus Router: Optimized for Xbox

[Rasmussen]

I'm posting this in case it might help someone eventually.

My LAN consists of an Asus RT-N66U router, to which are connected a switch and three other routers in bridge mode functioning as access points.

The UPnP server is a Win 7 PC running both Assett UPnP and MinimServer. A Mac hosts iTunes.

Initially, there were problems with MinimServer not showing up, or taking a long time to show up, and unable to maintain the connection. IGMP snooping was disabled on all devices, except the switch. After disabling IGMP snooping on the switch, MinimServer worked just fine and I've been very happy with its performance.

A few days ago, for reasons of security, I updated the firmware on the RT-N66U to the latest version (3.0.0.4.380.8120). It led immediately to massive degradation of DLNA over WiFI, as well as poor performance of AirPlay devices. MinimServer vanished from the list of servers, while Asset showed only after long delays, and was unable to maintain the connection reliably. This was only on WiFi -- Ethernet devices could see MinimServer and play reliably.

I checked IGMP snooping again, and it was still disabled on all devices. Eventually, the setting which restored the situation was Wireless > General > Wireless Mode > Optimized for Xbox. Checking this option for both the 2.4GHz and 5GHz bands fixed the problem and now MinimServer is back working reliably.

Asus documentation and tech support are below abysmal. There is basically no reliable information on what "Optimized for Xbox" does. According to one post in a forum it "makes the router report it does not support LDPC error correction". LDPC is commonly used in transmission of data over noisy channels, and it is included in 802.11n and later. Why it should have anything to do with multicast I cannot imagine.

[simoncn]

Thanks very much for this. I have an RT-N66U configured as a media bridge and running firmware 3.0.0.4.380_7266-g6439257. It is working very well at present and it sounds like I should stay with this firmware version.

[Peter StreamMagic]

(22-12-2017 19:17)simoncn Wrote:  Thanks very much for this. I have an RT-N66U configured as a media bridge and running firmware 3.0.0.4.380_7266-g6439257. It is working very well at present and it sounds like I should stay with this firmware version.

I also have an RT-N66U (firmware 3.0.0.4.380-7743-g2cf84e2) and have not updated to the latest version. At this moment this seems the right choice, everything is working perfect. For the long term stopping updating in general is not the best thing to do? In my experience outdated software leads to malfunctioning at some point!

Peter.

[Rasmussen]

As general rule, I'm disinclined to update any software. In my experience, updating software means minimum benefit with maximum headache -- unless one enjoys tinkering for the sake of it.

In this instance, however, I was forced to update when I discovered that my router was under attack (repeated attempts to change my DNS settings to point to an IP number located in Russia). Given the way things are, I'll be updating the router firmware promptly... however much I shudder at the thought...

[simoncn]

How did you discover that your router was being attacked?

[Rasmussen]

In an idle moment (waiting for a remote sync to complete) I had a look over my router's settings (I really don't know why). To my surprise, the DNS was set manually to an IP I didn't recognise. As a rule, I either get the DNS automatically from the ISP, or I set it to my ISP's closest server or to Google's well-known IPs. The IP was one of a block of numbers assigned to a Russian ISP. I set the router to get DNS automatically, rebooted it, but, within minutes, the setting was changed back to the Russian IP (w/o leaving any trace of it in the router's log). To cut a long story short, I determined that the change was either operated from the WAN side, or from malware resident on the router. Re-set to factory settings, changed log/pass, updated firmware, re-set to factory settings again, changed log/pass again. Since then, no more changes to router settings. Now I monitor router settings and behaviour on a regular basis and I intend to update firmware promptly. Btw, this https://www.trendmicro.com/cloud-content...outers.pdf makes for interesting reading.

[Pepsican]

(22-12-2017 19:17)simoncn Wrote:  Thanks very much for this. I have an RT-N66U configured as a media bridge and running firmware 3.0.0.4.380_7266-g6439257. It is working very well at present and it sounds like I should stay with this firmware version.

That's a very bold statement to make. Especially in the light of recent weaknesses found in WPA security and for the fact that the OP gives you the solution to the issue (the fact there is one means ASUS has done this per design and will not release any type of fix). I'd check the release notes as they're probably full of security fixes, either directly or through updates of components.

As a general rule, operating systems (Windows, iOS, Android etc) and firmware (DSM from Synology, router updates) should always run on the latest version for security reasons and they should be updated promptly when available.

[simoncn]

This is of course a valid point but I think it is also relevant that this router is configured as a media bridge and has no exposure to the internet.