Cisco Cisco Email Security Appliance C160 Mode D'Emploi
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Cisco AsyncOS 8.5.5 for Email Security User Guide
Chapter 4 Understanding the Email Pipeline
Incoming / Receiving
Figure 4-3
Email Pipeline — Delivering Email
Incoming / Receiving
The receiving phase of the Email Pipeline involves the initial connection from the sender’s host. Each
message’s domains can be set, the recipient is checked, and the message is handed off to the work queue.
message’s domains can be set, the recipient is checked, and the message is handed off to the work queue.
Host Access Table (HAT), Sender Groups, and Mail Flow Policies
The HAT allows you to specify hosts that are allowed to connect to a listener (that is, which hosts you
will allow to send email).
will allow to send email).
Sender Groups are used to associate one or more senders into groups, upon which you can apply message
filters, and other Mail Flow Policies. Mail Flow Policies are a way of expressing a group of HAT
parameters (access rule, followed by rate limit parameters and custom SMTP codes and responses).
filters, and other Mail Flow Policies. Mail Flow Policies are a way of expressing a group of HAT
parameters (access rule, followed by rate limit parameters and custom SMTP codes and responses).
Together, sender groups and mail flow policies are defined in a listener’s HAT.