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The primary network card would have its IP configuration setup set up so that it is visible on the data LAN. This allows playback of recordings by authorised users, as well as remote control of the Echo server, such as Remote Desktop Connection, if required.
The secondary network card would have its IP configuration setup set up so that 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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