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The recommended secure protocol for voice and video applications is the Secure<span> Real-time Transport </span>Protocol<span> (SRTP) protocol. SRTP is a Real-time Transport </span>Protocol (RTP) profile used to to provide encryption, message authentication and integrity.
The default cipher of SRTP is the Advanced Encryption Standard<span> (AES) .</span>
Explanation:
I think that you might have used it a lot or its just a glitch and will come back after some time.
It might be that your screen cracked.
But try re-booting if that does not work, wait and take off the battery.
When we focus on stereotypes we may <span>unconsciously look for information to support our generalizations .</span>
