Cisco Cisco Email Security Appliance C160 Guía Del Usuario
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Cisco IronPort AsyncOS 7.3 for Email Advanced Configuration Guide
OL-23081-01
Chapter 5 Email Authentication
Note
More settings are available via the CLI. See
for more information.
Step 6
If you choose a conformance level of SIDF-compatible, configure whether the
verification downgrades a Pass result of the PRA identity to None if there are
Resent-Sender: or Resent-From: headers present in the message. You might
choose this option for security purposes.
verification downgrades a Pass result of the PRA identity to None if there are
Resent-Sender: or Resent-From: headers present in the message. You might
choose this option for security purposes.
Step 7
If you choose a conformance level of SPF, configure whether to perform a test
against the HELO identity. You might use this option to improve performance by
disabling the HELO check. This can be useful because the
against the HELO identity. You might use this option to improve performance by
disabling the HELO check. This can be useful because the
spf-passed
filter rule
checks the PRA or the MAIL FROM Identities first. The appliance only performs
the HELO check for the SPF conformance level.
the HELO check for the SPF conformance level.
SIDF
The SPF/SIDF verification behaves according to
RFC4406.
RFC4406.
-The PRA Identity is determined with full conformance
to the standard.
to the standard.
- SPF v1.0 records are treated as spf2.0/mfrom,pra.
- For a nonexistent domain or a malformed identity, a
verdict of Fail is returned.
verdict of Fail is returned.
SIDF Compatible
The SPF/SIDF verification behaves according to
RFC4406 except for the following differences:
RFC4406 except for the following differences:
- SPF v1.0 records are treated as spf2.0/mfrom.
- For a nonexistent domain or a malformed identity, a
verdict of None is returned.
verdict of None is returned.
NOTE: This conformance option was introduced at the
request of the OpenSPF community
(www.openspf.org).
request of the OpenSPF community
(www.openspf.org).
Table 5-1
SPF/SIDF Conformance Levels
Conformance Level
Description