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The primary network card would have its IP configuration setup so it is visible on the data LAN. This allows playback of recordings by authorised users of the system, as well as remote control (of the Echo server, such as Remote Desktop Connection) of the Echo server , if required.
The secondary network card would have its IP configuration setup so it is visible on the SIP/telephone network. This will allow it to have mirrored traffic sent to it for monitoring and recording by the Echo server.
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