 | Copyright © 2008, Juniper Networks, Inc. All rights reserved. Trademark Notice. | |
Application system cache (ASC) saves the mapping between an application type and the corresponding destination IP address, destination port, protocol type, and service.
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Before You Begin |
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For background information, read: |
Once an application is identified, its information is saved in the cache so that only one pattern matching is required for an application running on a particular system, thereby expediting the identification process.
A mapping is saved in the cache only if the matched signature contains both client-to-server and server-to-client patterns. This process protects the system from hackers who might send malicious packets through a legitimate server port so that it is interpreted as a different application.
By default, the application system cache saves the mapping information for 3600 seconds. However, you can configure the cache timeout value by using the CLI.
To minimize the impact on performance, application system cache is refreshed only when TCP or UDP traffic triggers a cache lookup. Without a cache lookup, the entries in the ASC remain unchanged even after cache timeout.
| Copyright © 2008, Juniper Networks, Inc. All rights reserved. Trademark Notice. | |