The Pitch & Product
|ASUS IP Sharing Gateway Router with Integrated 4-port Gigabit Switch
|First consumer router with 4 port gigabit Ethernet switch that supports Jumbo Frames
|• Gigabit Ethernet with Jumbo Frame support
• Very fast routing speed
|• Uncompetitive routing features and user interface
• Large throughput hit for hosted server access
ASUS continues to try to innovate its way into the crowded consumer networking market. Although it’s not the first company to introduce a SOHO router with a built-in 10/100/1000 switch – that would be D-Link’s DGL-4300 [reviewed here] – it is the first to have that four-port switch support Jumbo Frames. Unfortunately, this spiffy little gigabit Ethernet switch comes as part of a router that’s nowhere near as impressive.
The RX3141 is about the size of a typical business tome with all indicators on the front and connectors on the rear. It’s not made for standing vertically on a desk, but has mounting screw slots on the bottom along with two reasonably strong magnets in case you’d like to throw it up onto the side of a file cabinet.
Figure 1 shows the router is powered by a Winbond W90N740 32-bit ARM7TDMI-based MCU. It has built-in support for two 10/100 Ethernet MACs and a USB 1.1 host controller hub with one port tranceiver.
Figure 1: RX3141 board
(click image to enlarge)
The gigabit switch comes courtesy of a Broadcom BCM5385, which is under the heatsink shown at the upper left-hand corner of Figure 1. This is the same switch used in the D-Link DGL-4300, but ASUS has chosen to enable the built-in Jumbo Frames capability, whereas D-Link did not.
TIP: Jumbo Frames are simply Ethernet frames (packets) larger than 1500 Bytes and you’ll see why supporting them is desirable when I review my test results. If you’d like additional background on Jumbo Frames try this article.
The rest of the design is pretty straightforward, with a Realtek RTL8201CP 10/100 Ethernet “PHYceiver” for the 10/100 WAN port, and 2 MBytes of flash and 16 MBytes of SDRAM.
The Pitch & Product, Continued
When you log into the 3141 at its default IP of 192.168.1.1, you’ll be greeted by a status page (Figure 2). I initially thought that the 3141 didn’t like Firefox when I clicked on the links in the left-hand nav bar because nothing happened. But when I got impatient and started repeatedly hammering on a link, it finally revealed the sub-menu below it.
This is the first time I’ve encountered the requirement to double-click on a link in a web-browser based interface and frankly, I think this is poor UI design. Double click may be expected for OS desktops, but a single click on a browser link should do the trick.
Other than the annoying double-clicking, navigation through the rest of the interface is quick and I didn’t encounter any long reboots required to save settings changes. Figures 3 – 6 provide a taste of what the controls look like, which casual networkers will probably find difficult to navigate. Note that the admin screens don’t scale with browser window width and the “help” info found in the right-hand column on each page makes for a particularly wide page.
Figure 3: PPPoE setup
Figure 4: Security settings
Figure 5: Inbound ACL setup
Figure 6: Virtual server setup
Given the state of the art in (relative) user friendliness found in routers from Linksys, D-Link and NETGEAR, the RX3141 pales in comparison. For example, I think many users will find the requirement to also set an inbound ACL rule for any virtual server or “special application” (triggered port mapping) to be confusing, annoying or both. And the lack of any on-screen prompt or “help” to inform you of this requirement just compounds the problem.
The routing feature set isn’t competitive with current routers, either. You won’t find content or parental controls (other than the difficult to understand non-schedulable outbound ACL feature), nor are there any bandwidth controls or Quality of Service (QoS) features either. And logging is bare-bones, given the lack of syslog or SNMP trap support and the fact that you can’t save, email, or even clear the log!
Jumbo Frame Test
Before running routing tests, I first wanted to check out the Jumbo Frames feature to see if it really could boost gigabit Ethernet throughput. I connected two systems running WinXP SP2 – one an Athlon 64 3000+ w/ 512 MB, the other a 2.4GHz Pentium 4 w/ 504MB.
Each machine had an Intel Pro 1000/MT desktop adapter with 18.104.22.168 (3/8/2005) driver. The adapters were both set to “Auto Detect” mode and reported connecting at 1000Mbps Full Duplex.
The adapters allow setting jumbo frame sizes of 4088, 9014 and 16128 Bytes. But since the RX3141’s switch supports only up to 9K frame sizes, I limited my testing to the 4088 and 9014 settings.
Figure 7 shows that average throughput got a little over a 30% boost when a 4088 Byte frame size was used (the top trace in the plot). But boosting frame size up to 9014 Bytes was counter productive, resulting in lower average throughput, but more importantly, higher throughput variation. This fallback in throughput at higher frame size is not due to anything in the 3141, but due instead to hardware and software limitations in the two computers used for the test.
Throughput Testing & The Verdict
Table 1 summarizes my Qcheck tests that show a big difference in inbound and outbound TCP routing performance with outbound almost 7 times faster! Note that you probably wouldn’t notice this difference unless you had a fiber or DSL2 / 2+ connection.
Build May 10 2005 11:38:48
|Table 1: Routing Performance Test results
Note: Details of how we test can be found here.
ASUS confirmed these results (although their testing showed 25Mbps inbound throughput), and said the difference is due to the extra processing that inbound traffic must go through (SPI and DoS, plus ACL and NAT). But they also pointed out that my WAN-LAN results didn’t represent throughput from transfers that originated on the LAN side of the 3141 – like most typical networking traffic. Instead, the Qcheck WAN-LAN test measured throughput from transfers originating on the WAN side of the router – like someone accessing an FTP, gaming or web server hosted on the router’s LAN side from the Internet would experience.
So I set up an FTP server on the WAN side of the router and used IxChariot‘s FTPput and FTPget scripts to check out ASUS’ explanation. Note that this was done without any virtual servers or Inbound ACL list rules since there are none needed for LAN-initiated transfers. The results confirmed ASUS’ assertions with average throughputs of about 83 Mbps and 86 Mbps for FTPput (LAN > WAN) and FTPget (WAN > LAN) respectively.
So is the RX3141 a good deal? It all depends on how much you value its support of Jumbo Frames. As I write this, it’s not in stock anywhere in the U.S. but has a lowest on-line price of $115. This compares well with D-Link’s DGL-4100 (the only other non-wireless gigabit Ethernet consumer router available) at $107. So you’re not paying a lot for the Jumbo Frames feature.
But where the 3141 disappoints is in its routing feature set and user interface, which are more reminiscent of earlier-generation products than what most of ASUS’ well-established competitors are currently producing. In particular the RX3141 has neither the DGL-4100’s GameFuel automatic QoS, nor its parental controls and schedulable port filtering, nor its more user-friendly controls.
So if gigabit is what you gotta have, but you can live without Jumbo Frames, you’d be better off – both in features and in money saved – by checking out D-Link’s GameFuel duo, or rolling your own solution with separate router and gigabit switch.