Installation guide

41
Unfortunately, there is no rule regarding which technology is the most reliant at present in Australia. It
depends on a variety of technological and vendor specific factors that vary from location to location.
If your location allows it, the combination of cable and (A)DSL would usually be the choice with the best
performance and lowest cost. In some locations, a wireless Internet provider might be an even better
substitute for either cable or (A)DSL.
Dual WAN ports
Some Internet gateway appliances (embedded router/firewall devices) allow more than one WAN (in this
case, ISP) connection. They can be set up to automatically switch over to the secondary provider if the
primary provider is not available.
For example – you have an (A)DSL provider and a cable provider. You connect WAN port 1 from your
gateway with your cable modem (since your cable service is faster and cheaper to use), and WAN port 2
of your gateway to your (A)DSL modem. You configure your gateway so that cable is used whenever
available, with (A)DSL as a backup that is used automatically when cable is unavailable, until cable
becomes available again.
Load balancing
If you have two independent Internet access methods, you may as well make the best of it. Why not boost
your performance by using both, instead of just using the secondary connection if the primary connection
fails?
Imagine somebody in your practice is downloading a huge radiology image, and your downloading software
is not smart enough to share bandwidth fairly. Everybody else would be almost locked out of Internet use
until the download finishes.
Load balancing can be done in principle with a single connection on a packet-per-IP basis, but it is far more
efficient and predictable if you have more than one physical connection to the Internet.
Load balancing in this case means that your Internet gateway (your firewall/router) takes care of everybody
getting a fair share of the available bandwidth.
If your router has load balancing features, it will allow you to route the network traffic through either
connection depending on criteria you can select in the router’s configuration:
• if load exceeds a certain percentage.
• on a particular day of the week or time of the day.
• depending on network traffic volume (there is a potential cost saving if you can avoid traffic
limits imposed by your contract).