Symantec Security 5600 Series, Security 5400 Series,Clientless VPN 4400 Series, Administration Manual

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735 Field descriptions
Assets field descriptions
Parameters for smtp—General tab
These parameters let you further customize the behavior of the SMTP protocol.
Associated tasks
None.
Table D-216 Parameters for smtp—General tab
Field Description
Service Group Name Unique name for this service group. This field is read-only.
Protocol Name Protocol with which you are currently working. This field is read-only.
Soft Recipient Limit Maximum number of recipients that are handled on a single message. The
remainder are told to retry. This entry is typically set to the total number of
users behind the security gateway. This does not affect the SMTP protocol, but
it makes it more difficult for someone interested in sending spam. The
minimum soft limit defined in the SMTP RFC is 100. Although it is not
recommended, you can set a lower value.
The default is 0, which means no limit.
Hard Recipient Limit Maximum number of recipients that are handled on a single message. If this
limit is reached, the whole message is denied. This limit should be set higher
than the soft limit and higher than the number of recipients of an average
legitimate message. The minimum hard limit defined in the SMTP RFC is 100.
Although it is not recommended, you can set a lower value.
The default is 0, which means no limit.
Hide Internal Domain Hides the source domain of mail messages from outside users. Received lines
that match the hidden domain name are replaced by the message: private
information removed. Suppression is for a single block of received header lines.
Sender Domain Checked Forces the sender’s address to be validated by checking the format and
ensuring the domain name is fully qualified. It also checks whether an MX
record exists for the domain name in DNS. Email from recipients who fail the
DNS registration test is rejected.
This option is unchecked by default.
Source Routing Rejected Causes the SMTP proxy to refuse all email to addresses specified using source-
routing syntax. If you do not specify recipient domains and you do not check
this option, you are allowing all mail through with no conditions and opening
yourself up to being used as a spam relay site. If you have specified recipient
domains, enabling this feature is not necessary in most cases.
This option is unchecked by default.
Reject Short Packet Connections Automatically disconnects all connections that appear to be regular users using
a Telnet client.
This option is unchecked by default.
Loose Recipient Check
Performed Enables the use of the % character in the mail recipient syntax as well as the
use of the ! character. If this feature is not enabled, email to recipient addresses
with those characters is rejected.
This option is unchecked by default.
Loose Sender Check Performed Enables the use of the % character in the mail sender syntax as well as the use
of the ! character. If this feature is not enabled, email sent from addresses with
those characters is rejected.
This option is unchecked by default.