Strategies for Connecting Your Content Security Appliance

Keep the following in mind when connecting your appliance :

• Administrative traffic (CLI, web interface, log delivery) is usually little compared to email traffic.
• If two Ethernet interfaces are connected to the same network switch, but end up talking to a single interface on another host downstream, or are connected to a network hub where all data are echoed to all ports, no advantage is gained by using two interfaces.
• SMTP conversations over an interface operating at 1000Base-T are slightly faster than conversations over the same interfaces operating at 100Base-T, but only under ideal conditions.
• There is no point in optimizing connections to your network if there is a bottleneck in some other part of your delivery network. Bottlenecks most often occur in the connection to the Internet and further upstream at your connectivity provider.

The number of interfaces that you choose to connect and how you address them should be dictated by the complexity of your underlying network. It is not necessary to connect multiple interfaces if your network topology or data volumes do not call for it. It is also possible to keep the connection simple at first as you familiarize yourself with the gateway and then increase the connectivity as volume and network topology require it.