DNS uses UDP as transport protocol - Networking

Q.  Networking: Which one of the following uses UDP as the transport protocol?
- Published on 19 Oct 15

a. SMTP
b. HTTP
c. Telnet
d. DNS

ANSWER: DNS
 

    Discussion

  • Prajakta Pandit   -Posted on 26 Oct 15

      - The Domain Name System (DNS) is a hierarchical distributed naming system for computers and services or any resource connected to the Internet or a private network.

      - DNS uses UDP as the transport protocol.

      - DNS is the client server application. A host which wants to map a name to address or vice versa, calls a DNS client named as resolver.

      - DNS uses alias names for identifying the sender and receiver instead of an IP address. So the alias address has to be mapped to the IP address.

    Importance of Domain Name System (DNS)

      - The Domain Name System distributes the responsibility of assigning domain names and mapping those names to IP addresses by designating authoritative name servers for each domain.

      - Authoritative name servers are assigned to be responsible for their supported domains and may delegate authority over sub-domains to other name servers.

      - This mechanism provides distributed and fault tolerant service and was designed to avoid the need for a single central database.

      - DNS identifies the sender and receiver so they should be known to each other.

    What is the working flow of the Domain Name System (DNS)?

      - When the name < -- >address mapping is necessary a host calls a resolver.

      - The resolver then accesses the closest DNS server with a mapping a request.

      - If this server has the requested information, it satisfies the resolver but if it does not have the requested information, then it refers the resolver to ask other servers to provide the information.

      - The resolver receives the mapping and then checks for an error and if it finds an error it free delivers the mapping to the requesting process.

Post your comment / Share knowledge


Enter the code shown above:
 
(Note: If you cannot read the numbers in the above image, reload the page to generate a new one.)