Cisco Cisco Email Security Appliance C170 Guia Do Utilizador

The Cisco IronPort appliance must always be able to identify a unique interface 
over which a packet will be delivered. To make this decision, the Cisco IronPort 
appliance uses a combination of the packet’s destination IP address, and the 
network and IP address settings of its Ethernet interfaces. The following table 
summarizes the preceding examples:

Keep these things in mind when connecting your Cisco IronPort appliance:

Administrative traffic (CLI, web interface, log delivery) traffic is usually 
small 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 will be 
slightly faster than ones 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 Cisco IronPort appliance 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.

Allowed

Allowed

Not Allowed

Allowed