Use two ISPs to improve speed and reliability

For mission critical applications, having two ISPs makes sense.  

Many of today’s cars are rolling computer networks
. The high performance, clean emissions, and good fuel mileage of modern cars are the result of electronic sensors, controls, and communication everywhere inside our cars. Add features such as active suspension, traction control, collision avoidance, navigation, and advanced entertainment, and today’s cars can be a handful to diagnose and repair when something breaks.


Car manufacturers want to ensure that each module (engine control, transmission control, passenger restraint, etc.) is up to date. For example, when replacing one module in a modern BMW, the car must be connected via the Internet to BMW in Germany. Then BMW Germany’s program scans the car, and if any module’s firmware is out of date, the program requires that all modules’ firmware be brought up to date, a process that may require hours to complete. BMW warns that neither DC power to the car nor its Internet connection may fail during the update process, or the (expensive) module may be killed by the aborted update process. (The computer industry calls this "bricking" a system, because it’s transformed into a . . . brick.)


Jason Athanas (pictured), president of Autobahn Performance of Oakland Park, needs a high-reliability full-time broadband Internet connection. His company, which is a leading independent automobile service shop, moved from DSL service to Cbeyond’s business grade T1 service, which has proven to be very reliable. Now they’ve added Comcast Cable as a second ISP (Internet Service Provider). Why a cable TV provider? Comcast’s cable plant is unlikely to follow the same route as the T1 line, so if one ISP’s cable fails, it’s unlikely that the other ISP will fail from the same cause.  This should pay off if/when a major storm blows through!
The ingredient that allows simultaneous load balancing between the two ISPs is the Cisco Small Business RV082 10/100Mbps 8-Port VPN Router.  It required hours on site to get this installation working smoothly; there are many variables to configure, and not all of them work as expected. I’m sure that the next installation will go more quickly, now that I’ve learned what doesn’t work. 


How well does it work? Testing reveals that Cbeyond’s T1 up- and down-load speeds are a consistent 1.4 Mbps (Megabits per second), while Comcast’s speeds are all over the map, from 3 Mbps to 14 Mbps (download). By checking the RV082’s system log, we’ve already seen daily brief interruptions in Comcast’s service. I’m impressed with the RV082’s performance so far: users benefit from the sum of the two ISP’s data rates, and they are unaware of Comcast’s service interruptions. It’s the best of both worlds.
The RV082 also includes a stateful packet inspection firewall, the ability to create VLANs (virtual LANs) and VPNs (virtual private networks), plus the usual NAT and DHCP functions. By using VLANs, we’ve created a secure Internet wireless access point for use by customers in the waiting room, and using VPNs, we allow secure remote access via the Internet, so that Jason and his staff may check the security cameras, work on orders, etc. . . . from anywhere that there’s an Internet connection.

This system upgrade is already paying for itself: it’s money well spent.

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