Cisco Cisco Email Security Appliance C160 Mode D'Emploi

Submit and commit your changes. 

You can define the behavior of the appliance while modifying the message encoding for the following 
parameters:

Headers

Untagged non-ASCII headers

Mismatched footer or heading encoding

Set the length of time AsyncOS will allow an unsuccessful inbound 
connection to remain intact before closing it.

An unsuccessful connection can be an SMTP conversation in which SMTP 
or ESMTP commands continue to be issued without a successful message 
injection occurring. When the specified timeout is reached, the behavior is 
to send an error and disconnect:

“421 Timed out waiting for successful message injection, disconnecting.”

A connection is considered unsuccessful until it successfully injects a 
message.

Only available for SMTP connections on public listeners. The default value 
is 5 minutes.

Set the length of time AsyncOS will allow an inbound connection to remain 
intact before closing it.

This setting is intended to preserve system resources by enforcing a 
maximum allowable connection time. Once about 80% of this maximum 
connection time is reached the following message is issued:

“421 Exceeded allowable connection time, disconnecting.”

The appliance will attempt to disconnect when the connection exceeds 80% 
of the maximum connection time in order to prevent disconnecting 
mid-message. It is likely that a problem is occurring with the inbound 
connection if it is open long enough to reach 80% of the maximum 
connection time. Keep this threshold in mind when specifying the time limit.

Only available for SMTP connections on public listeners. The default value 
is 15 minutes.

Messages having subject size within the specified limit will be accepted and 
any other messages will be rejected. If you set this value to 0, no limit is 
applied.