WAN and WWAN
The MBR-900 has two WAN interfaces. The primary WAN interface is an RJ45 port that can be connected to a Cable, DSL, or other Ethernet based connection. It supports standard DHCP connections, as well as Static IP, PPPoE, L2TP, and PPTP connections.
I tested the MBR900 on my DSL connection and ran a speed test on speedtest.net showing my DSL runs at 12.61Mbps down and .65Mbps up, which is the typical speed for my DSL service.
The secondary WAN interface is a USB port for connecting to a 3G/4G USB modem. The MBR900 supports a huge list of current 3G/4G modems, which you can see on the supported devices section of the MBR900 product page.
I used a Virgin Wireless Novatel MC760 USB modem with VM's BroadBand2Go prepaid service for my testing. Setting up the USB modem on the MBR900 was plug and play. I didn’t configure a thing, and didn’t have to power cycle the router. Detection and configuration of the modem was automatic.
Further, I found that I could simply insert and remove the USB modem without power cycling or rebooting the router. As you can see in Figure 6, the MBR900 accurately detected the make and model and enabled the modem. Note that I had to handle account setup and data purchase before connecting the modem to the MBR900.
Figure 6: MBR900 WWAN modem detection
To test the MBR900’s USB modem performance, I ran multiple speed tests to speedtest.net. First, I directly connected the modem to my laptop and ran the speed tests. Then, I connected the modem to the MBR900 and ran the same speed tests to see if there were any significant differences in throughput over the router and laptop.
As noted in a Cradlepoint whitepaper on WiPipe, “mobile environment(s) change from session to session,” so I ran multiple tests and reported the average numbers in Table 2 below. My average download speed with the modem and my laptop was 747kbps and average upload was 392kbps. My average download speed with the modem connected to the MBR900 was 740kbps and average upload was 320kbps.
|Download (Kbps)||Upload (Kbps)|
Table 2: 3G throughput
The results from speedtest.net varied dramatically from test to test, more than they did on my DSL line, validating Cradlepoint’s comment about how the mobile environment can change with each session. I suspect that if I continuously ran the tests on my laptop and the MBR900, the averages for both would have been nearly identical.
The MBR900 performs an upload speed estimation on the WAN interface when the automatic traffic shaping option is enabled. (I’ll describe this option more in the QoS section.) Unfortunately, the MBR900 inaccurately reported my DSL upload speed at 1518kbps and my USB Modem’s upload speed at 4215kbps, so I wouldn’t rely on the MBR’s link measurements.
In real world use, I found Internet surfing via the MBR900 over both my DSL connection and the 3G USB modem to be quite smooth. Obviously, I had better performance over the faster DSL connection, but my experience over the 3G USB modem seemed reasonable.
The default configuration is for the primary interface to carry all outbound traffic, with the secondary interface to be a backup in case the primary fails. The MBR900 can be used with only a Cable or DSL Internet connection, only a 3G/4G modem, or both.
I tested failover from primary to secondary, and then tested failback from secondary to primary. I used a basic process to test failover and failback. Before I started, I made sure both interfaces were up and the router was on the primary interface, and started a continuous ping to the Internet. To test failover, I disconnected the primary interface and timed how long before the ping restored, indicating the router has successfully failed over to the USB Modem on the secondary interface.
As you can see below, only 4 pings dropped as the router automatically enabled the USB modem and directed all traffic out that interface. I repeated this test several times, it took on average 20-30sec for failover to complete.
Figure 7: WWAN failover test
To test failback, I reconnected the primary interface and timed how long before the ping restored and the router showed the primary was back in service. As shown below, only 1 ping dropped as the router automatically re-enabled and re-directed all traffic out the Ethernet WAN interface. I repeated this test several times, it took on average 5-15sec for failback to complete.
Figure 8: WWAN failback test
For failback to work properly, you have to enable the failback option, shown below. Personally, I think failback to the primary interface should be enabled by default. I'm not sure why you wouldn't want failback to happen automatically.
Figure 9: Failback option enable
Although the MBR-900 has two WAN interfaces, I hesitate to call it a Dual WAN router, as most Dual WAN routers allow for the use of both WAN interfaces at the same time. The MBR-900 will run either interface and failover between the two, but does not have options for running both interfaces simultaneously. The MBR-900 has options to reverse the order and make the USB interface primary and the Ethernet interface secondary.
I tested another router that supports 3G USB modems nearly two years ago. The NETGEAR MBR624GU is a bit dated now, with only an 802.11b/g radio and lesser functionality than the Cradlepoint MBR900. Of note, the Netgear device came with a cable/dongle accessory for positioning the USB modem upright and improving reception, shown below. I used that Netgear accessory with the Cradlepoint to improve 3G signal strength, and recommend Cradlepoint look into a similar accessory.