The router supports QoS but this feature lacks any documentation (the user manual only shows a screenshot while the integrated help system doesn’t know anything about it at all). So I can only give you the names of the options available here. By the way, these traffic management options only refer to data sent from the router to the Internet. After specifying your bandwidth, you can prioritize your traffic in four categories. Then you choose traffic filters and assign one of the priority levels to them. A filter contains sender and recipient addresses, packet size, TCP/UDP port pairs or a specific application. QoS requires quite a lot of processor resources, so it may be not good for a high-speed Internet connection (for example, the router’s connection speed would slow down by half when I enabled QoS in PPPoE mode in my environment).
There are as many as five pages with settings related to the Wi-Fi access point. On the first page you choose the wireless standard (b/g/n, b/g or n) and network SSIDs. The TEW-691GR allows establishing as many as four networks with different names and security settings. They will of course share the same channel bandwidth. It is not possible to limit their access to the LAN or Internet but you can choose whatever channel number you want. There is no integrated network scanner. A few additional options are available for 802.11n: channel 20 or 20/40, guard interval, MCS, additional channel number. Like with the above-described adapter, most of these parameters can only be set at Off or Auto, which prevents the user from fully controlling the router. Another odd thing is that the number of options and their names differ from those of the TEW-687GA adapter. That’s not handy. By the way, the two devices even have different default passwords.
The wireless module supports WDS technology which can be used to combine several access points into a single pool. The data-transfer speed lowers considerably in this mode, though.
The advanced options offer some more Wi-Fi related settings such as transmission signal level and RT Threshold.
Security parameters can be specified independently for each SSID. The TEW-687GA supports open networks, WEP, WPA and WPA2 (also with Radius server). WPA2-AES is recommended in 802.11n mode to achieve maximum performance. White and black lists of client MAC addresses can be filled in to restrict their access to the access point. The router supports quick setup with WPS technology. You can start the process by pressing the WPS button on its case or via the web-interface.
The last page from this group shows the currently connected clients, their operation mode, speed and signal level.
Most of the pages in the Advanced group refer to the ways that PCs on the local LAN can be accessed from the Internet. The simplest of them is to specify a client machine’s address in the DMZ option. No filtering of requests to that machine will be done then but this works for one computer only. To forward one port, you can go to the Virtual Server page and choose such parameters as rule name, client address, protocol type (TCP, UDP or both), external and internal port numbers. You cannot enter port ranges or port lists. An operation schedule and a filter of remote IP addresses can also be specified. There can be multiple schedules for different days of the week and different hours of the day. As for the filter, its rules have the format of permitting/restricting access from a remote address. The purpose of this option isn’t quite clear but you can use it in conjunction with port translation to permit an internal service to be accessed from a particular IP address only.
If you need to forward multiple ports simultaneously, you have to give up the opportunity to have different internal and external port numbers. This feature is supposed to be used mainly for gaming applications, so it is called Gaming and contains a number of predefined settings for games (but also for a few P2P applications).
The third way of opening ports can be used for games, too. It works in semiautomatic mode. When an outgoing connection from a client is identified on a certain port, port translation is enabled.
There are a few additional network options here. You can set up a routing table, enable RIP, allow the ping command from the WAN port, and enable the UPnP protocol. I wouldn’t recommend the latter for security reasons due to the lack of any monitoring options.
Like most NAT routers (by the way, you cannot disable NAT in this device), the TEW-691GR has multiple ALGs for such protocols as FTP, SIP, RTSP and some others. If you don’t need them, you can turn them off individually.
The Access Control page is where you can restrict the access to different Internet services. One way is to choose a range of client addresses, a range of ports, and a schedule. There is a predefined list of applications here. If you want to block all access for certain clients, you can enter them into the IP Range Block Rule List. The simplest way to block websites is to add their URLs into the URL Filter Rule List.
Like most other routers, the TEW-691GR allows you to change the admin password, update its firmware, and save/restore its configuration. It has an integrated dyndns.com client and an option for accessing the setup interface from the Internet. There is an integrated clock which is used for the abovementioned firewall scheduling only. The router doesn’t keep any logs, which is rather odd for a top-end model. You can learn the status of the device, including its Internet connection status, on a separate menu page.
Frankly speaking, I had expected a somewhat friendlier interface from this router. Although it offers all the basic options you may need, some features are downright inconvenient, for example your having to reboot the router after changing many of its parameters.