How does a software echo canceller work?

Question

I read many topics echo VoIP echo, for example What is echo cancellation? Echo causes

And that’s what I understand. Suppose there are A and B, and A hears his own voice (echo)

• Its B, which causes an echo. Because the B-microphone captured the voice of voice B and B-speaker (which contains voice A)
• Since B echoes, it must perform echo cancellation on its side. This echo cancellation works as follows: B will save a copy of A’s voice and check if B will send this copy. If so, B must subtract this copy from the transmitted data.

Is it correct? Please correct me if I am wrong

Answer 1

AEC , (2) , AEC. :

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