Hi Steve,
Internet multihoming is a very near and dear issue to me, mostly because there is not a scalable multihoming standard out there short of BGP (which is out of the cards for most of my clients). Over the years we have always recommended T1 circuits for voice and data applications, primarily because of the SLA. As you are aware, consumer grade broadband connections have been blowing up lately with providers offering a lot of bandwidth for next to nothing... So it is a very frequent occurrence that a client calls me and tells me their T1 at the office is painfully slow because they are used to the 20+Mb line they have at home. We are currently trying to get all of our customers onto Ethernet circuits, but in the mean time we have a problem.
So what we have been doing over the past few years is recommending to get a DSL circuit and a cable circuit in addition to the T1 and plugging them into a WAN management device to load balance all of the internet traffic. Here in South Florida AT&T and Comcast consumer grade circuits go up and down like the sun, but the chances of the T1, DSL and Cable lines all going down at the same time are pretty slim (short of a hurricane). On top of that, it also takes AT&T at least 3 months to deliver any kind of business class circuit (with an acceptable SLA). So we also run into situations where customers need internet delivered quickly and our only option is to go with a cheap consumer grade circuit until a business class circuit can be installed. This solution works for the folks that aren't ready to step up to an Ethernet line for their primary connectivity, but it requires that we have a device that can handle at least 3 WAN links.
I occasionally run into situations where only a failover link is required, and I always use Cisco equipment for this. Most times I am in a situation where the customer needs to be able to load balance, failover and utilize PBR for multiple WAN links. We have been using the following device to address these issues.
http://www.ecessa.com/pages/products/products_powerlink_pl100.php
I haven't tried using the SA500 device just yet. Does it satisfy the feature requirements that I need short of the number of WAN links it supports?
Thanks,
Cole
