Cisco Cisco Email Security Appliance C190 User Guide

These values are explained in 

The maximum number of outbound connections that will be 
made by the IronPort appliance to a given host. (Note that the 
domain can include your internal groupware hosts.) 

The maximum number of messages allowed for a single 
outbound connection from the IronPort appliance to a given host 
before initiating a new connection.

The maximum number of recipients allowed within the given 
period of time. “None” denotes that there is no recipient limit for 
the given domain. 

The minimum period of time — between 1 and 60 minutes — 
that the IronPort appliance will count the number of recipients. 
Specifying a time period of “0” disables the feature. 

If you change the recipient limit, AsyncOS resets the 
counters for all messages already in the queue. The 
appliance delivers the messages based on the new 
recipient limit.

Specifies whether the limit will be applied (enforces) to the 
entire domain or to each mail exchange IP address specified for 
that domain. (Many domains have multiple MX records.) 

This setting applies to connection, message, and recipient limits.

Specifies whether the limit will be applied system-wide or for 
each Virtual Gateway address. 

If you have configured groups of IP addresses, but you 
have not configured virtual gateways, do not configure 
apply limits per each virtual gateway. This setting is 
intended only for systems configured to use virtual 
gateways. For information on configuring virtual 
gateways, see 

.