The DNS protocol works when your computer sends out a DNS query to a name server to resolve a domain. For example, you type "www.firewall.cx" in your web browser, this triggers a DNS request, which your computer sends to a DNS server in order to get the website's IP Address !
DNS is a distributed database that contains mappings of DNS domain names to data. It is also a protocol for Transmission Control Protocol/Internet Protocol (TCP/IP) networks, defined by the Requests for Comments (RFCs) that pertain to DNS. Dynamic Host Configuration Protocol (DHCP) is used to dynamically (automatically) assign TCP/IP configuration parameters to network devices (IP address, Subnet Mask, Default Gateway, DNS server etc). Dynamic Host Configuration Protocol (DHCP) is described in RFC 1531. DNS Protocol The ascii diagrams in this section are taken from RFC 1035 . A resolver (user program, such as dig) sends a query to a name server, and server returns a response. Dec 30, 2019 · Protocol: The name of the protocol must be proceeded by an underscore (_) and followed by a period (.). The protocol could be something like _tcp. Domain: The name of the domain that will receive the original traffic for this service. Priority: The first number (10 in the example above) allows you to set the priority for the target server. You Step3 ask the root domain name server: If the ISP server doesn’t know where the domain name you are querying, then you need to query the root name server. The 13 DNS server roots in the world act like a DNS phone book-like role. Although they don’t know the IP address of the address you are looking for, they can direct you to know the address.
The request then goes to the Domain Name Server, which holds the information about the site and its IP address. Once the IP address is discovered, it is sent back to the client, which can now use
Part of the confusion associated with the DNS protocol is that it lacks a special name. Thus DNS can refer either to the entire system, or to the protocol that makes it work. This page documents the protocol, which operates in one of two basic modes - lookups or zone transfers. DNS Lookups. Normal resource records lookups are done with UDP. DNS is a distributed database that contains mappings of DNS domain names to data. It is also a protocol for Transmission Control Protocol/Internet Protocol (TCP/IP) networks, defined by the Requests for Comments (RFCs) that pertain to DNS.
Follow these steps to make your DNS server accessible over IPv6: Setup IPv6 on your DNS server—here is a tutorial which shows how to do this in BIND installed on Debian. Add IPv6 addresses as a DNS record for your hostname, so it has both A (IPv4 address mapping) and AAAA (IPv6 address mapping) records. Here is an example of an AAAA record:
The Hypertext Transfer Protocol (HTTP) is an application-level protocol for distributed, collaborative, hypermedia information systems. HTTP has been in use by the World-Wide Web global information initiative since 1990. The first version of HTTP, referred to as HTTP/0.9, was a simple protocol for raw data transfer across the Internet. DNS tunneling is a misuse of DNS. Domain Name Servers (DNS) have been called the internet’s equivalent of a phone book.DNS tunneling attempts to hijack the protocol to use it as a covert communications protocol or a means of data exfiltration. Jan 14, 2014 · DNS stands for domain name system. It is an application layer protocol used to provide a human-friendly naming mechanism for internet resources. It is what ties a domain name to an IP address and allows you to access sites by name in your browser. The DNS protocol is well-documented online, however, we describe the salient pieces here for clarity. Note, however, that the oﬃcial reference for the DNS protocol are the requests for comment (RFCs) that cover DNS (namely, RFC 1035). The RFC itself should be considered au-thoritative, most of the primer below is borrowed from the RFC itself. Types of DNS Entries DNS is used not just for name to address resolution But also for finding mail server, pop server, responsible person, etc for a computer DNS database has multiple types Record type A ⇒ Address of X Record type MX ⇒ Mail exchanger of X CNAME entry = Alias name (like a file link), "see name" The Domain Name System (DNS) protocol is used primarily to find out the IP address of a computer, given its domain or host name.It is because of the DNS protocol, human beings are able to associate meaningful names to computers, instead of remembering the IP address of each computer.