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You will then receive a file with the name "isgw_SerialNumberOfTheGateway.licencelicense".
To install the license in your gateway, go to "Miscellaneous" under "Preferences" and upload the licence license under "SIP to SIP License".
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Available licences and upgrades
Different SIP2SIP licenses are available:
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Upgrades are available from license 4 to 8 and from 16 to 32.Please see