Pergunta de entrevista da empresa Concentrix

-What is the difference between SMTP and HTTP? -What is the DNSSEC? -What is VOIP and SIP? -Difference between hard phone and soft phone. -There's a customer, who is trying to connect to MS outlook, when he opens up outlook, at the bottom of the screen he sees disconnected. How can we troubleshoot this? -How is Mac address different from IP address?