Cisco Cisco Email Security Appliance C160 Mode D'Emploi
Chapter 2 Configuring Routing and Delivery Features
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Cisco IronPort AsyncOS 7.1 for Email Advanced Configuration Guide
OL-22164-02
Using Virtual Gateway™ Technology
This section describes IronPort Virtual Gateway™ technology and its benefits,
how to set up a Virtual Gateway address, and how to monitor and manage Virtual
Gateway addresses.
how to set up a Virtual Gateway address, and how to monitor and manage Virtual
Gateway addresses.
The IronPort Virtual Gateway technology allows you to configure enterprise mail
gateways for all domains you host — with distinct IP addresses, hostname and
domains — and create separate corporate email policy enforcement and anti-spam
strategies for those domains, while hosted within the same physical appliance.
gateways for all domains you host — with distinct IP addresses, hostname and
domains — and create separate corporate email policy enforcement and anti-spam
strategies for those domains, while hosted within the same physical appliance.
Note
The number of Virtual Gateway addresses available to you depends on the model
of your IronPort appliance. Some appliance models can be upgraded to support
more Virtual Gateway addressed via a feature key. Contact your IronPort sales
representative for more information about upgrading the number of Virtual
Gateway addresses on your appliance.
of your IronPort appliance. Some appliance models can be upgraded to support
more Virtual Gateway addressed via a feature key. Contact your IronPort sales
representative for more information about upgrading the number of Virtual
Gateway addresses on your appliance.
Overview
IronPort Systems has developed a unique Virtual Gateway technology designed to
help ensure that corporations can reliably communicate with their customers via
email. Virtual Gateway technology enables users to separate the IronPort
appliance into multiple Virtual Gateway addresses from which to send and receive
email. Each Virtual Gateway address is given a distinct IP address, hostname and
domain, and email queue.
help ensure that corporations can reliably communicate with their customers via
email. Virtual Gateway technology enables users to separate the IronPort
appliance into multiple Virtual Gateway addresses from which to send and receive
email. Each Virtual Gateway address is given a distinct IP address, hostname and
domain, and email queue.
Assigning a distinct IP address and hostname to each Virtual Gateway address
ensures that email delivered through the gateway will be properly identified by the
recipient host and prevents critical email from being blocked as spam. The
IronPort appliance has the intelligence to give the correct hostname in the
ensures that email delivered through the gateway will be properly identified by the
recipient host and prevents critical email from being blocked as spam. The
IronPort appliance has the intelligence to give the correct hostname in the
SMTP
HELO
command for each of the Virtual Gateway addresses. This ensures that if a
receiving Internet Service Provider (ISP) performs a reverse DNS look-up, the
IronPort appliance will match the IP address of the email sent through that Virtual
Gateway address. This feature is extremely valuable, because many ISPs use a
reverse DNS lookup to detect unsolicited email. If the IP address in the reverse
DNS look-up does not match the IP address of the sending host, the ISP may
assume the sender is illegitimate and will frequently discard the email. The
IronPort appliance will match the IP address of the email sent through that Virtual
Gateway address. This feature is extremely valuable, because many ISPs use a
reverse DNS lookup to detect unsolicited email. If the IP address in the reverse
DNS look-up does not match the IP address of the sending host, the ISP may
assume the sender is illegitimate and will frequently discard the email. The