Asus RT-N16

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The ASUS RT-N16 is a Single Band N-Router (2.4GHz only) with lots of RAM (128Mb) and FlashRAM (32Mb), so it is well equipped to run DD-WRT

The ASUS RT-N16 is in the 100Mbps+ Routing class, meaning it can route at higher speeds than a 100Mbps WAN connection can handle, but it does not even attempt to approach GigaBit WAN performance. Performance details below.

If you are looking for a Dual Band N-Router (both 2.4GHz and 5GHz bands) also with lots of RAM (256MB) and FlashRAM (32Mb), you could take a look at the ASUS RT-N66U. If you are looking for a cheaper router, but still with DD-WRT Mega specs (and USB port) you could take a look at the Asus RT-N10U Single Band N-Router with 32Mb RAM and 8Mb FlashRAM.


Unit RAM = 128 MB (2x 64MB - Samsung K4N511163QZ-HC25 or 2x 64MB - Samsung K4T51163QG-HCE6)

Unit Flash = 32 MB (MACRONIX MX29GL256EHTI2I-90Q)

Unit NVRAM = 32K

Unit CPU = Broadcom 4716, 533 MHz (Factory clocked to 480MHz)

use command cat /proc/cpuinfo in a terminal program like puTTY to get the full CPU details

USB ports = USB2.0 x 2

Stock Power Supply = 12V - 1,25A max (Upgrading the Power Supply)

Ethernet Ports = WAN x 1 RJ-45 for 10/100/1000 Base T, LAN x 4 RJ-45 for 10/100/1000 Base T

Antennas = 3 x external detachable 2dBi antennas

WiFi Operating Frequency = 2.4GHz ~ 2.5GHz

802.11n Draft = up to 300Mbps

802.11g = 6, 9, 12, 18, 24, 36, 48, 54Mbps

802.11b = 1, 2, 5.5, 11Mbps

Unit Switch Chip = Broadcom BCM53115SKFBG

Color of LEDs = Blue

Main board

This shows the main board for the Asus RT N16 along with the location for the JTAG headers.
This shows the main board for the Asus RT N16 along with the location for the JTAG headers.

Installation Instructions

Install DD-WRT from Factory Firmware

Please note: Details of the DD-WRT firmware build variations are found here. More current build information can be found in the Peacock announcement thread. See Where do I download firmware? for links.


  • Restore Factory Default settings (Clear NVRAM)
  • Install the INITIAL ASUS RT-N16 K26 mini version of DD-WRT (file name ends in .trx)
  • Restore Factory Default settings (Clear NVRAM) or via DD-WRT webGUI
  • Upgrade to temperary K3X build 21530 (from 2013) (file name ends in .trx or .bin, mega or big)
  • Restore Factory Default settings (Clear NVRAM), or via DD-WRT webGUI
  • Upgrade to latest K3X mega or big build (*.trx and N16 in the name), see Where do I download firmware for links.


  1. Do a Restore Factory Default settings in the Asus GUI. Asus factory default username/password is admin/admin. Let the router reboot. Disconnect all cables (WAN, USB, etc.) and plug the Ethernet cable from your PC into the LAN1 port on the router.
  2. Download the INITIAL dd-wrt firmware, located here :
    • Recommended Build for initial flashing: (2013) 22118 K2.6_mini_RT-N16.trx found in the broadcom K26 folder.
  3. Flashing the INITIAL Firmware to the router (the one where the file name ends in .trx)
  4. Set the router in "Recover mode" (same as other Asus routers)
    • Use ASUS Firmware Restoration Utility to upload the new firmware (from router CD or here). or search for Asus Recovery Utility.
    • You need to set the PC to Static IP (Static IP guide)
    • Set the router in recovery mode by holding in the reset button when plugging in the power. The power light should now be blinking slowly, meaning the router is in restore/recovery mode and ready for the new firmware. Upload and wait for the router to reset on its own (may take anywhere from 3 to 15 minutes).
    Note on Asus Recovery Utility: The recover utility is basically a fancy tftp server, with added wait timer, so non-windows users may use standard tftp tools to upload firmware, just remember to do the proper wait for 3 minutes or more, for the unit to re-boot on its own, after the 10 to 30 seconds of tftp'ing is done. Inspiring tftp guides: Tftp_flash, Asus_TFTP_Flash
  5. After the reboot from flashing, wait for the device to show the password change screen for DD-WRT. Enter root as the user and anything for the password as you will do the user/pass procedure again after the final flash.
  6. Do a Reset to Factory Settings.
    • Method A - Use the DD-WRT GUI. Goto Administration -> Factory Defaults -> click Yes -> select Apply Settings.
    • Method B - Do a hard reset. The following procedure will clear out the NVRAM and set dd-wrt back to default values:
      • With the unit powered off, press and hold the Red WPS button on the back of the unit.
      • Without releasing the WPS button plug the power in, and hold the WPS button for 30 seconds
      • When releasing the WPS button the unit will reboot and Factory Default settings will be loaded.
    Note on hardware reset to clear the NVRAM: ASUS units have a different reset procedure than Linksys units. The above described method actually works on the RT-N16! See also Eko Forum note
  7. Do not skip the above step! Reset is IMPORTANT and recommended BEFORE and AFTER every firmware flash espcialially when changing kernels or large upgrades (eg. K26->K3X or 21530->33772).
  8. Upgrade to the dd-wrt firmware dd-wrt.v24-21530_NEWD-2_K3.x_big.bin from the broadcom_K3X folder under 2013. See Where do I download firmware for links. This time you can use the web interface to do the upload. Administration -> Firmware Upgrade. Select Reset to Defaults.
  9. Upgrade to the latest K3X big build from the betas folder, this time do not reset settings. See Where do I download firmware for links.

Reward yourself for reading and following these instructions with a cold beverage of your choice. Enjoy DD-WRT on the RT-N16! Also, please consider donating to DD-WRT as we are an open-source community providing free software to upgrade consumer routers with commercial-grade capabilities.

Also read Basic Wireless Settings and Advanced Wireless Settings to learn how to get the most WiFi data speed out of your new N-Router.

Troubleshooting flashing issues

IF the router won't provide a Power LED after updating to the K3.x file...then there is a problem with the flash chip and it needs to be cleared (except the CFE). Issue the following commands via telnet/SSH or the Commands window under the Admin tab.

mtd erase nvram mtd erase ddwrt mtd erase linux

This will clear the flash start the process again with the K2.6 mini build

Notes about K3X on Asus N16

Do NOT issue "erase nvram" command from CLI...this unit only has 64K of nvram...the CLI thinks it has 128K and the firmware thinks its 256k...this means doing an "erase nvram" removed other parts of the flash chip (likely firmware partition "dd-wrt" or "linux")

Note: build 21530 seems to have wireless broadcasts the ssid...but you can't connect to it...however, if in repeater bridge mode, you can contact it through the host AP at the router's IP address.


  • NAT Loopback (Port Forwarding) is broken in builds 15760-19969 (see this thread for a workaround)
    • 15962, 17990, & 18000 are Recommended Builds which would require this workaround
  • Special thanks to Eko for making the initial work on getting the RT-N16 to work with DD-WRT!

Upgrading DD-WRT

If DD-WRT is already loaded on your router, you can flash firmware using these steps

  1. Download firmware from one of the sites listed: Where do I download firmware
    • Go to the Broadcom K3X folder, then download the ***K3.x-big-RT-N16.trx file.
  2. Open the DD-WRT's web interface in your web browser and open (the default).
    • (Only necessary if coming from a very old build) Do a Restore Factory Default settings (Clear NVRAM). Let the router reboot.
  3. Open the DD-WRT's web interface in your web browser. Upload/upgrade the firmware using the
  4. Administration tab -> "Firmware Upgrade" button.
  5. Click "browse" button -> select the downloaded file -> click "Upgrade" button. It will take about 2-5 minutes to upload and write the flash. Your browser should reboot when it is done.
    • (Only necessary if coming from a very old build) Do a Restore Factory Default settings (Clear NVRAM). Let the router reboot.
    • As an alternative to step 7, on the Upgrade page, select "Reset to Default settings" for "After flashing, reset to". This is to automatically reset to Factory Default settings when it reboots, but Step 7 is the recommended method.
  • Note: For newer builds, please read the "New Build" or router-specific threads. See Where do I download firmware for more info on New build threads.

How to restore to factory firmware

  1. Download the latest ASUS firmware from the ASUS web site [1]. Or go to with a client FTP.
  2. Rename the asus file from .trx to .bin
  3. Do a Restore Factory Default settings (Clear NVRAM) while DD-WRT is still loaded on your router.
  4. Go into the DD-WRT firmware upgrade page, set it to reset defaults, and select the ASUS firmware you renamed.
  5. After the flash finishes, and the router has re-booted, you see the ASUS GUI.
  6. Do a Factory Reset to clear the NVRAM (using the Asus web gui)
  7. Try to enjoy ASUS's firmware, and keep missing DD-WRT (fortunately you can just flash back to dd-wrt again when ever you want)

Known Issues, Bugs, and Workarounds

  • Hardware fix (capacitor) for RT-N16 wireless drop-outs [2]
  • UPNP is currently not working for the RT-N16, so for now leave the feature disabled unless you want a full CPU Load. FIXED with SVN Changeset #13527
  • Access Restriction with MAC-Filter doesn't work on Asus RT-N16. FIXED Ticket #1319 (as of 12/18/09)
  • On this router the reset button will only bring you to recovery mode. If you wish to restore defaults, use the Red WPS button while plugging power in. Post By Eko
  • Rflow data reports only on upload traffic (Ticket #1139). Further discussion in this thread (only affects those using/enabling Rflow).
  • USB hard drives after build 15407: "The devs of dd-wrt have removed the loading of file system drivers from the startup of the firmware. They are now loaded on demand with automount. Well, this presents a problem for those of us with USB HDD that automount doesn't detect. In order to load the file system drivers at startup you need to add the following to save startup in the commands tab" for more, see TechInfoDepot DD-WRT Notes

NVRAM and K3X Builds (Not necessary)

  • The installation instructions above have been updated to include redhawk0's procedure to K3X.
  • The RT-N16 only has 32K of NVRAM on k2.6 builds, due to limitations within the CFE coding, and some users have reported their routers rebooting and resetting due to running out of NVRAM.
  • K3X builds have expanded the default nvram partition via software. However, getting K3X to run on this model can be tricky, `erase nvram` can cause a soft brick, requiring TFTP. redhawk0's procedure is here, also read the RT-N16 Condensed thread starting here

NVRAM Usage Reduction

  • Using traff (Traffic graph in Status_Internet.asp) or UPnP will cause the NVRAM to fill up quickly, causing router functions like ddns to stop functioning. Upon the next reboot the router will reset it self to firmware defaults. Disable traff and/or UPnP to prevent this, or flush the traff stats occasionally.
  • Note on traff: Status -> WAN -> (at the buttom) Data Administration -> button "Delete" flushes the traff stats. Services -> Services -> WAN Traffic Counter -> ttraff Daemon: Disable -> Apply settings, will stop the collection of traff data. You may however just choose to reset/delete traff data every month, and the traff data will not take much room in the NVRAM
  • Note on UPnP: Access to UPnP settings: NAT/QoS -> UPnP. In newer builds (Spring 2012) UPnP is disabled by default.
  • Note on monitoring NVRAM usage. In newer builds (spring 2012) NVRAM usage/max is displayed on the front Web GUI at "Space Usage"

NVRAM Reduction Scripts

  • Save the following as a startup script, it will remove initialized variables that are stored in NVRAM and currently have no value assigned to them (This cleared up nearly 5K of NVRAM in my experience).
       rm /opt/tmp/nvramshow
       nvram show >> /opt/tmp/nvramshow
       while read -r line; do
       if [[ "$val" == "" ]]; then
               nvram unset $var
       i=`expr $i + 1`
       if [[ $i == 50 ]]; then
               sleep 2
       done < /opt/tmp/nvramshow
       exit 0

Simpler version: Instead of outputting to a file to check if each var is empty, use grep to find empty vars:
1. Check current size and empty var count

       root# nvram show  | grep =$ | wc -l
       size: 30273 bytes (2495 left)

2. Clean up

       root# for line in `nvram show  | grep =$ `; do var=${line%*=}; nvram unset $var; done
  • This can be saved as a startup script. Alternatively, to avoid further NVRAM usage, save to JFFS or USB with a JFFS partition. Save your script to /jffs/etc/config, give it a .startup extension, make it executable, then DD-WRT will run it after every boot.

3. Check again....

       root# nvram show  | grep =$ | wc -l
       size: 24307 bytes (8461 left)

4. Saved almost 6K

       root# echo "$((8461 - 2495))"


By factory default the cpu is clocked at 480 MHz and the Ram at 240 MHz. Overclocking at CPU 532 MHz / Ram 266 MHz can be achieved with these commands in a Telnet/SSH session :

  • nvram set clkfreq=532,266
  • nvram get clkfreq [to verify]
  • nvram commit && reboot

Note :

  • Not recommended: instability issues can arise from overclocking / overheating
  • See also Overclocking BCM 47xx CPU's for more info
  • Adding a heat sink to the SoC is recommended, and/or a fan

More information here (with pictures) to prevent overheating issues with heat sinks:

Recovery Mode

This router does have a recovery mode if ever needed for flashing, and to access it, press the WPA button (not the reset button like other ASUS), then plug in power, and tftp the firmware you want to flash. Don't forget to do a Factory Reset in the GUI before and after every flash to make sure you don't have any nvram problems or conflicts. On this router reset button only resets the nvram partition. If you wish to use tftp to restore defaults, use the wps button while plugging power in.

If you have bricked your Asus RT-N16

  1. You could try to Hardware reset it to Factory Defaults by holding in the red WPS button while plugging in the power. Eko Forum note
  2. You could try to use the Recovery mode, and upload a different firmware.
  3. You could use the serial connector (inside the router) and use CFE-level commands. Use 3.3V TTL level signaling. For example Sparkfun FTDI Serial adapter (US shop) a small and very reliable unit providing: Virtual Serial port via PC USB to 3.3V-TTL (Rx, Tx) Serial signaling. UK outlet
  4. You could try to reset/reload the firmware using the TJTAG software and the JTAG connector inside the router.

Upgrading the Power Supply

A higher amperage power supply (adapter) for the Asus RT-N16 is possible. Please take a look at this :


Test Description	Throughput - (Mbps)
WAN - LAN	                 141.1
LAN - WAN	                 143.3
Total Simultaneous      155.9
Max. Connections         200
Firmware Version

Sources: [3] Testing methods: [4], [5]