Like every other website on the planet, SmallNetBuilder uses cookies. Our cookies track login status, but we only allow admins to log in anyway, so those don't apply to you. Any other cookies you pick up during your visit come from advertisers, which we don't control.
If you continue to use the site, you agree to tolerate our use of cookies. Thank you!

Router Charts

Click for Router Charts

Router Ranker

Click for Router Ranker

NAS Charts

Click for NAS Charts

NAS Ranker

Click for NAS Ranker

More Tools

Click for More Tools

LAN & WAN Reviews

Routing Performance

NOTE!Testing Notes:
WAN to LAN tests are all run with LAN endpoint in DMZ
LAN to WAN tests are run with LAN endpoint not in DMZ, except UDP Stream

Like SMC's 7004VBR, the SX has a SPI-based firewall that has the ability to disable the SPI features and fall back to plain-old NAT as its firewall mechanism. This makes testing a little more complicated, but gives us more insight into the drag that SPI places on the router's performance.

If you compare the results in the chart above to other recent SPI-based routers, you see the SX beats them by a wide margin, especially on the WAN-LAN tests, which typically run under 2Mbps on other products. But the SX's almost 17Mbps throughput beats the other guys for best-case SPI-disabled performance, too!

If you really want to be impressed, though, check out the chart below. This table, which I also did for the SMC7004VBR review shows Throughput and Response time results for various combinations of DMZ and SPI. Remember that WAN-LAN tests can be run only with DMZ on, so that's why there are no DMZ off results for that direction.

Case Number

Test Description

Intrusion Detection Settings DMZ

Transfer Rate (Mbps)

Response Time (msec)
[100,000 Byte data size]



SPI enabled (defaults) on


48 (avg)



SPI disabled on


1 (avg)



SPI enabled (defaults) off


48 (avg)

LAN-WAN SPI enabled (defaults) on 12.2 65 (avg)


SPI disabled on


1 (avg)

LAN-WAN SPI disabled off 32.3 1 (avg)

I couldn't believe the 33Mbps throughput results either, so I double-checked the Qcheck results by doing a Chariot run, which showed that the throughput actually varied from 26 to 38Mbps!!! Un-bee-leeve-able!

Conclusion? Let's just say that you can run the SX with whatever settings you want and not even think twice about the throughput effects of your choice.

Routing Performance Test Results

Test Description Transfer Rate (Mbps) Response Time (msec) UDP stream
Throughput (kbps) Lost data (%)
WAN - LAN 16.8 48 (avg)
74 (max)
499 0
LAN - WAN 16.6 48 (avg)
56 (max)
493 0
Firmware Version 1.43 May 22 2002

More LAN & WAN

Wi-Fi System Tools
Check out our Wi-Fi System Charts, Ranker and Finder!

Support Us!

If you like what we do and want to thank us, just buy something on Amazon. We'll get a small commission on anything you buy. Thanks!

Over In The Forums

After updating to 384.18, all 8 of my Nest Protect devices went offline, and I was unable to add any new Protect devices onto my account. I have one 2...
Hi all,I'm using a (new in Dec 2019) RT-AX88U with Merlin 384.18 firmware, and previously 384.17 etc. I've always been running Merlin on this box. Thi...
I was having problems with my RT-AC3100 after four years and decided to bite the bullet and purchase a new RT-AX88U. After unwrapping and plugging int...
Hi!I'm owner of RT-AC3100m using a asuswrt-merlin firmware (384.17) with Entware installed on WD 1TB USB3 HDD. On router I have installed ruTorrent 3....
Is the RT-ACRH17 still being supported with firmware updates? It's been over a year since the last update and I'm wondering if this is a dead product....

Don't Miss These

  • 1
  • 2
  • 3