Cisco ESA uses a multilayer approach to fight viruses and malware. The first layer of defense consists of outbreak filters, which the appliance downloads from Cisco SenderBase. Outbreak filters use global threat intelligence and behavioral analysis to identify and block emerging threats before they reach the network. The second layer of defense consists of antivirus engines, which scan the message body and attachments for known viruses and malware. Cisco ESA supports multiple antivirus engines, such as Sophos, McAfee, and Cisco AMP. The Sophos engine is one of the default engines that Cisco ESA uses, along with McAfee. The Sophos engine provides fast and accurate detection of viruses and malware, and updates its signatures frequently. The other options are not features that are used to configure Cisco ESA with a multilayer approach to fight viruses and malware. A white list is a list of trusted senders or recipients that are exempt from spam or virus filtering. RAT is the Recipient Access Table, which is used to determine whether the appliance accepts or rejects messages to a recipient address. DLP is Data Loss Prevention, which is used to prevent sensitive or confidential data from leaving the network. References :=

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