Cisco Cisco Email Security Appliance X1050 Guía Del Usuario
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Cisco IronPort AsyncOS 7.3 for Email Advanced Configuration Guide
OL-23081-01
Chapter 5 Email Authentication
The Received-SPF Header
When you configure AsyncOS for SPF/SIDF verification, it places an SPF/SIDF
verification header (
verification header (
Received-SPF
) in the email. The
Received-SPF
header
contains the following information:
•
verification result - the SPF verification result (see
•
identity - the identity that SPF verification checked: HELO, MAIL FROM,
or PRA.
or PRA.
•
receiver - the verifying host name (which performs the check).
•
client IP address - the IP address of the SMTP client.
•
ENVELOPE FROM - the envelope sender mailbox. (Note that this may be
different from the MAIL FROM identity, as the MAIL FROM identity cannot
be empty.)
different from the MAIL FROM identity, as the MAIL FROM identity cannot
be empty.)
•
x-sender - the value of the HELO, MAIL FROM, or PRA identity.
•
x-conformance - the level of conformance (see
) and whether a downgrade of the PRA check was
performed.
The following example shows a header added for a message that passed the
SPF/SIDF check:
SPF/SIDF check:
Received-SPF: Pass identity=pra; receiver=box.example.com;
client-ip=1.2.3.4; envelope-from="alice@fooo.com";
x-sender="alice@company.com"; x-conformance=sidf_compatible
Note
The
spf-status
and
spf-passed
filter rules use the received-SPF header to
determine the status of the SPF/SIDF verification.