Getting Started13To protect against unauthorized access and tampering of sensitive information (e.g.,login password, registration information), you can encrypt configuration files usingYealink Configuration Conversion Tool. AES keys must be 16 characters and thesupported characters contain: 0 ~ 9, A ~ Z, a ~ z, and the special characters # $ % * +,- . : = ? @ [ ] ^ _ { } ~. For more information on how to encrypt configuration files, refertoYealink Configuration Conversion Tool User Guide.AES keys must be configured on the phone before the auto provisioning process. AESkeys are configurable via web user interface at the path: Settings->AutoProvision->Common AES Key (and MAC-Oriented AES Key).When configuring some particular features, you may need to upload resource files to IPphones, such as personalized ringtone file, language package, logo file. Yealinkprovides some resource file templates for the particular features. Ask the distributor orYealink FAE for resource file templates. The following provides information on how tocustomize resource files and specify the access URL for the resource files.Yealink IP phones have built-in system ringtones. You can change the ring type, orcustomize a ringtone and upload it to the phone via auto provisioning.The ringtone file must be PCMU audio format, mono channel, 8K sample rate and 16 bitresolution.The ringtone file format must be *.wav.The ringtone file uploaded must be within 100KB.###################################################### Configure the access URL of the customized ringtone ######################################################ringtone.url =#ringtone.delete =http://localhost/all#Delete all the custom ringtones uploaded through auto provisioningringtone.delete =For example, enter “tftp://192.168.1.100/Ring9.wav” in the “ringtone.url =” field. Duringthe auto provisioning process, the phone connects to the provisioning server“192.168.1.100”, and downloads the ringtone file “Ring9.wav”.For more information on customizing a ringtone file, refer to Customizing a RingtoneUsing Cool Edit Pro on page 59.