Yes if you use the Skype to Skype mode than Skype has secure your voice and data by using the encryption. It set under the privacy policy to secure your call. Skype call is encrypted not using the Skype but also if you are using the cell phone or your local PSTN lines. It is full proof system to secure your call to gives the security. Your conference call is also encrypted to get the services. In conference call, you are using the conference call than PSTN by taking care of encrypted code. You can view on padlock to get the status of the encryption.
Skype provides the monthly payment to get the services by subscribing the Skype users. It depends on the Skype plan to select proper plan to make the subscription to take care of monthly subscription. You just have to refer the plan and get the coverage. It is one of the most suitable ways to get the unlimited call too. You can pay additional charges while making the payment for the Skype users.
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