0

Hey I just started to learn Networking and I have some problems understanding the DNS and DHCP. I tried many books but they defined it a total technical language and I can't understand them. So can anyone please explain me those terms in easy languages and in easy terms

closed as too broad by Teun Vink Sep 24 '16 at 12:23

Please edit the question to limit it to a specific problem with enough detail to identify an adequate answer. Avoid asking multiple distinct questions at once. See the How to Ask page for help clarifying this question. If this question can be reworded to fit the rules in the help center, please edit the question.

  • Besides this question being too broad, one could argue this is expected to be common knowledge on this forum. – Teun Vink Sep 24 '16 at 12:23
0

DNS is used for access to websites using an easy address like http://google.com instead of technical address http://74.125.224.72.

enter image description here

When you enter to http://google.com your computer first check its own DNS cache to looking for the ip (If you have entered before it would be here). If the ip cannot be found, the request is sent to the local DNS server. If it still cannot be found then the request is sent to the Domain Root Server. Finally the ip is sent to the host and saved in the cache for future requests.

A graphic example: enter image description here

DHCP is a protocol used by the router to assign automatic the private ip address to each device in a network. There is 3 ways to assign ip addresses automatic to the hosts:

  • Manual Assignment: The admin manually configure the ip addresses for the client in the DHCP server. When one host ask for one IP address, the server check the MAC address from the host y assigns the ip configured by the admin.
  • Automatic Assignment: The first time that one host is connected, the DHCP server assign an ip randomly.
  • Dynamic Assignment: The DHCP server assign an ip address temporarily. When the time is over the request has to be renovated.

Is not a technical definition but I think it can help you to have a global idea.

  • By Domain Root Server do you mean the DNS servers marked as com DNS Server and org DNS Server or the one marked as Root DNS Server in the diagram provided by you – Jøê Grèéñ Sep 24 '16 at 14:03
  • I mean the one marked as Root DNS Server. When the Root DNS Server receives a request, it answers with the TLD: Top Level Domain which can be .com or .edu for example. Then it looks for the IP address in the DNS tables from the TLD. For example: -Request Ip Address of Google.com to the Root DNS Server. -It answers that it is in the .com TLD and not in .net or .edu TLD. -Then looks for the IP address in the .com TLD. – dperezac Sep 24 '16 at 15:17
  • Protocols above OSI layer-4 are explicitly off-topic here. This question (if the focus were more narrow) and answer are more appropriate for Server Fault or Super User. – Ron Maupin Sep 24 '16 at 16:06

Not the answer you're looking for? Browse other questions tagged or ask your own question.