-| The **Extensions** define the information needed to regiser to the SIP accounts.
+| The **Extensions** define the information needed for an endpoint such as a hard phone, soft phone or some other device. The extension is the SIP username and password and together they are a key part of the credentials needed to authenticate to the server.
* Extension
* Extension
Enter the alphanumeric extension. The default configuration allows 2 - 7 digit extensions.
Enter the alphanumeric extension. The default configuration allows 2 - 7 digit extensions.