Cisco Cisco Email Security Appliance C170 Guia Do Utilizador

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Cisco AsyncOS 8.5.5 for Email Security User Guide

Chapter 7 Defining Which Hosts Are Allowed to Connect Using the Host Access Table (HAT)

SenderBase Settings and Mail Flow Policies

Significant Bits HAT Policy Option

The HAT syntax allows for the signficant_bits configuration option. When editing the default or a
specific mail flow policy in a HAT (for example, when issuing the

listenerconfig -> edit ->

hostaccess -> default

command) the following questions appear if:

•

rate limiting is enabled, and

–

using SenderBase for flow control is disabled, or

–

Directory Harvest Attack Prevention (DHAP) is enabled for a mail flow policy (default or
specific mail flow policy)

For example:

This feature also appears in the GUI in the Mail Policies > Mail Flow Policies page.

Figure 7-3

Enable the HAT Significant Bits Feature

Do you want to enable rate limiting per host? [N]> y

Enter the maximum number of recipients per hour from a remote host.

[]> 2345

Would you like to specify a custom SMTP limit exceeded response? [Y]> n

Would you like to use SenderBase for flow control by default? [N]> n

Would you like to group hosts by the similarity of their IP addresses? [N]> y

Enter the number of bits of IP address to treat as significant, from 0 to 32.

[24]>