Cisco Cisco Email Security Appliance C170 Guia Do Utilizador

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Cisco IronPort AsyncOS 7.3 for Email Advanced Configuration Guide
OL-23081-01
Chapter 2      Customizing Listeners
SMTP Address Parsing Options
To access the SMTP address parsing options, expand the section by clicking on 
SMTP Address Parsing in the listing.
Figure 2-6
Listeners SMTP Address Parsing Options
SMTP address parsing controls how strict the AsyncOS address parser behaves 
for the SMTP “MAIL FROM” and “RCPT TO” commands. SMTP address 
parsing has two modes: Strict and Loose as well as several other parsing options 
(configured independently of the address parsing mode). 
Selecting a parsing mode or type is deciding whether you want your appliance to 
strictly adhere to the standards of RFC2821.
Strict Mode
Strict mode tries to follow RFC 2821. In Strict mode, the address parser 
follows RFC 2821 rules with the following exceptions/enhancements:
  –
Space is allowed after the colon, as in “MAIL FROM: 
<joe@example.com>”.
  –
Underscores are allowed in the domain name.
  –
“MAIL FROM” and “RCPT TO” commands are case-insensitive.
  –
Periods are not treated specially (for example, RFC 2821 does not allow 
a username of “J.D.”).
Some of the additional options below may be enabled which technically 
would violate RFC 2821.