The TP-Link TD-W9970 is a low cost router with ADSL.VDSL2 modem. It is 802.11B/G/N compatible and has excellent WiFi performance. In addition power consumption is less than 5 Watts, it has low running costs, network accessible storage and more. This router will work as a replacement router if you have ADSL, ADSL2, ADSL2plus or VDSL service. As my broadband service is ADSL2plus, this review will be for ADSL2 performance.
VDSL (Very High Speed Digital Subscriber Line), is also called FTTC (Fibre to the Cabinet) in the UK. This is a hybrid connection, where fibre is provided to the street cabinet only, the line from the cabinet to your house is your regular copper or aluminium cable. As long as the distance from home to cabinet is not too long, then VDSL performance will be faster than ADSL2. VDSL2 performance will not be tested here.
This router is available from Argos, Amazon online and other retailers in the UK and is currently around £37.
SpecificationsBelow are the general specifications, remember that these can be changed by the manufactuer and you can also read the full spec online at TP-Link's website.
Design and AppearanceThe TD-W9970 modem/router is available in white only and has a nicely moulded case with no sharp edges and plenty of ventilation on both top and bottom of the case. The rear panel has two full wavelength 12.6cm antennas giving the 2.4GHz signal a 5dBi boost. This is 5 times greater than any router having an internal antenna. The antennas are fixed and cannot be removed but can be rotated or moved front or back to enhance signal direction. Because these antennas are so efficient less power is required for WiFi and the router runs cool to the touch.
Setup and User InterfaceFull instructions can be found in the manual or online, but to setup this router requires a laptop or PC with Ethernet cable, connected to one of the yellow Ethernet ports. Open the web browser on the computer (firefox, google chrome or Internet explorer) and enter 192.168.1.1 in the address bar. The default username and password are both set to "admin" lowercase, without the quotes. The router will automatically detect if your connection is ADSL or VDSL and after a few minutes, a connection to your service provider will be established. In easy setup mode a drop-down menu where you can select a list of ISP's and then you need to enter your network password and network username. This will be given to you when you signed up for internet service, in case of doubt contact your ISP.
Status Screen (Left)
Once your router has been configured, you may want to check the status screen. The DSL screen will show you some basic line information about your connection. The TD-W9970 uses a Broadcom modem chip-set which are very good . The current line rate, is the speed of your connection, negotiated by the modem chipset and your ISP's exchange line card. The line attenuation is determined by length and quality of your phone line and SNR margin, which is dynamic and can change is a compromise between speed and stability. The SNR value can only be changed by your ISP and getting this wrong can make the difference between an unstable connection and a line that is too slow. It is worthwhile choosing an ISP that can set this up properly for you. Zen Internet have an extremely reliable service record and excellent customer service.
DHCP Screen and LAN Configuration (Right)
By default the TP-Link routers are set to an IP address of 192.168.1.1 If you are upgrading from another router with a different network address, it may be convenient to reconfigure the LAN on the TD-W9970 router to match your old network settings. The DHCP settings screen, shown right allows you to do this. (If all your devices are wireless then you do only need to change the default gateway address.) If you have wired devices and wish to reserve some static IP address then change the Start IP address to octet 64 and the End IP address octet 253. In this example the network address is 192.168.1.0/24 The router is configured as 192.168.1.254 and the LAN address pool range starts at 192.168.1.64 to 192.168.1.199. IP address range 192.168.1.2-63 and 192.168.1.200-253 are therefore reserved and will not be handed out by the DHCP server. These addresses can be used for devices that require a static IP or network storage, print servers, etc..
Warning It is most important that the first three octets of the gateway address, start and end address of the LAN pool are the same, otherwise you may not be able to use your network. If you make a mistake, there is a reset hole on the back of the router to take configuration back to factory default.
The WiFi configuration is shown left. Here you can change the SSID of your router. the channel number, channels 1 through 13 are available, wireless mode, B, G or N and the channel width. Provision is made for a second SSID and you can configure a guest network if required, on another menu. The wireless security menu allows you to enter your encryption settings and a unique wireless password.
ADSL PerformanceYou can test your speed on sites such as Speedtest.net Results should be taken as an indication only . To measure accurately would require a site being able to handle multiple simultaneous requests and hence infinite bandwidth. There is no guarantee that the path from your ISP to the site being tested is good. Speed results vary according to time of day and amount of internet traffic. In the UK all internet traffic is routed via docklands, so choosing a server near London will often show a lower latency than a local server.
Of all the features of this TP-Link router, one of the most impressive is the power consumption. Shown left the power taken from the mains is just 4 Watts ! The supplied dc power supply is rated at 12Volts dc at 1 Amp, but the reason this router runs cool is simply its power consumption.
Now take a look at the right screenshot. This router has a software controlled WiFi scheduler. When WiFi is switched off, power consumption falls to 3.8 Watts !
One reason for this is that WiFi only transmits on the 2.4GHz band. The other reason is with two large external antennas are much better at delivering a stronger signal than any other router with an internal antenna. A router with a small 1 inch internal antenna has to send a lot more energy into the antenna to get a similar range In fact my last router consumed about 15 Watts of power day and night, which is typical of many routers with internal antenna.
FirewallA good firewall is often a consideration in choosing a new router. Although you can use a software firewall on your PC, having a decent firewall in your router leaves your CPU cycles free for other tasks.The Shields Up site by Steve Gibson provides a good importunity to probe all common ports on your network.
Many router firewalls fail this test but the TD-W9970 firewall passes this test. The firewall configuration menu also allows you to create new firewall rules, schedule a rule at a particular time, create inbound or outbound rules or create rules for TCP, UDP or ICMP packets, quite a versatile firewall.
Network StorageThe back panel has a single USB socket. A USB hard drive or memory stick can be used for storage and read by all devices on the network. Supported file systems are FAT32 and NTFS and the router can be setup as a samba share or FTP server. A guide to using the FTP server on windows is below:
The WiFi performance is one of this routers best features. Note also,that this router only provides 2.4GHz, and not the 5GHz band. As all wireless devices are backward compatible with 2.4GHz this should not be a problem, and for the same transmit power, the 2.4GHz has twice the reach of the 5GHz band.
WiFi uses the Industrial, Scientific and Medical (ISM) band of the radio spectrum. This band shares frequencies with blue-tooth, wireless alarms and baby monitors, video senders and other devices and can be very crowded. One way to avoid this is to use the 5GHz band, but 5GHz has a shorter wavelength of 6cm and is therefore much more heavily absorbed passing through walls and ceilings than 2.4GHz.
When WiFi was introduced in 1997, default channels were 1, 6 and 11. This gave 5 clear channels of separation and no interference between channels. Now, in 2020, these are still the default channels and unless you have lots of space, or very few neighbours. you will most likely get impaired WiFi performance due to same channel or cross channel interference.Avoiding Interference
If changing from default channels of 1, 6 and and 11 does not work, then an intermediate channel such as 3 or 4 or 8 or 9 can often boost performance. You can loose as much as 90% of your signal if you are on the same channel as a neighbouring signal and between 5 and 60% if you are on adjacent channels. Alternatives to WiFi Analyzer for Android are Netstumbler on Windows, and LinSSID or Wavemon for Linux.
wlan0 IEEE 802.11 ESSID:"LV426"
Mode:Managed Frequency:2.447 GHz Access Point: AC:84:C6:08:99:22
Bit Rate=72.2 Mb/s Tx-Power=20 dBm
Link Quality=37/70 Signal level=-73 dBm
The figues highlighted in red show that even with a weak signal of -73dBm. (router set to transmit on 20mW at 50%) an atill impressive Bit Rate of 72.2Mbps is negotiated. The results from iperf are below:
$ iperf -c 192.168.1.253 -p 2000 -t 10
Client connecting to sofia, TCP port 2000
TCP window size: 43.8 KByte (default)
[ 3] local 192.168.1.3 port 37206 connected with 192.168.1.8 port 2000
[ ID] Interval Transfer Bandwidth
[ 3] 0.0-10.0 sec 50.4 MBytes 42.2 Mbits/sec
WiFi SchedulerThe WiFi scheduler is a feature not often seen on some routers. You can control the time when WiFi is enabled. This can be set daily or hourly. Note that the router time is set to UTC, this is the same as GMT but does not move forward for Summer Time. Do you have difficulty sleeping at night ? A condition called electrosensitivity is where some people are more sensitive to electric and magnetic fields than others. Although not proved medically Turning off WiFi at night may help.
Also in the wireless menu is transmit power. You can turn the signal from 100%, down to 50% or 20%. This will save a slight amount of power and useful if you only want WiFi over a small area.
Should you consider this router, what are the good and bad points?
Well first the bad points, the modem is for ADSL/VDSL2, will not work as a cable modem. The 4 LAN ports run at 100Mbps, WiFi is 2.4Gpbs B, G, and N compatible only. There are faster wireless routers, but they only run as fast as the weakest link in your system. Even at 100Mbps on the LAN this is faster than the fastest VDSL2 connection currently at 80Mbps, so this should not put you off.
Now the good points. Low power consumption of under 5 Watts. Two external 5dBi antennas. The 5dBi is a reference that the antenna has got effectively 5 times more gain than an internal antenna (the small "i" in dBi). The signal is much better than any router with an internal antenna and you have the ability to select a channel. The firewall is robust and passes the Shields Up test. There is facility for USB network storage and a WiFi scheduler. At under £40 this is great value for money and for the price I would highly recommend this router.