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Dissecting DNS

Dissecting DNS - Wireshark Tutorial

From the course: Wireshark Essential Training

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Dissecting DNS

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- [Instructor] Domain Name System or DNS resides at the Application Layer of the OSI Model. DNS is an important protocol, as it maps a host name to an IP address. It uses UDP port 53 for requests and uses TCP port 53 for zone transfer. With DNS, a client will send a query to a DNS server for an IP address. The server will respond with the information. The server can ask other DNS servers for the information. With DNS, there's a number of types of records. Some commonly seen records are a type A record, that's for an IP version 4 address. You might also see a mail exchange record. This will redirect mail to a mail server. And a quad A. This shows the IP version 6 address. Now, why is it called quad A? Well, IP version 4 is a 32-bit address. IP version 6 has 128 bits, it's four times as large as an IP version 4 address, and that's why it's called a quad A. Within the DNS header, you'll see questions, answers, authority…

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