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How does a newlyinstalled personal computer connected to an Ethernet discover the IPaddresses of local servers?

How does a newly-installed personal computer connected to an Ethernet discover the IP addresses of local servers? How does it translate them to Ethernet addresses? How does it get an IP Address?

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1. The computer gets its IP address from a DHCP server, whether it is an actual server or a router.When it is first connected to the network, Windows automatically joins whatever workgroup your other machines are on.
2. That is actually a complex question. First you have to understand that there are many ways to get the information, but it all boils down to protocols. It depends on the type of communications you are using and encapsulation of data within the packets and frames, etc. etc. There is a lot of technical things going on under the hood but I am going to give you a generic answer for each of those questions and I'll post some sources for you to get the details. Q...How does a newly-installed personal computer connected to an Ethernet discover the IP addresses of local servers? A...I assume your talking about a PC that already has an address and want to know how it is able to communicate with other servers without having the address for them to begin with. the answer to this is DNS (Domain Name System). Basically when your computer is looking for a name of a server, your computer goes to the DNS server and ask it for an address. It responds back with the answer. (It could respond back with the wrong answer which is a form of DNS attack) To see this in action. go to a command prompt and type the following without the quotes. "PING www.google.com" You will get one of the many addresses google uses with their web site. put the address in your browser address bar and it will take you right to google. Q...How does it translate them to Ethernet addresses? A...This is ARP (Address Resolution Protocol) The ethernet address is the hardware address of your NIC. It is unique all over the world. Each different manufacturer is assigned the first 4 bytes of this address, then the rest is incremental. every single NIC will be unique, and this is really the level the communications takes place on. Without this, all the IP address in the world would not be possible. It is basically a table of Hardware addresses and the coresponding IP address. you can see these by dropping to a command prompt and typing "arp -a" without the quotes. Q...How does it get an IP Address? A...This is done via DHCP. DHCP is a service which hands out information to connecting nodes. It tells your computer what IP address it can use, what server is used for DNS and a a lot of other information. Odds are your computer is using DHCP. If you go to a command prompt and type "IPCONFIG /ALL" (without the quotes) and press enter, you will see the DHCP server address, DNS server address, your IP address, subnet mask, etc. etc. In case your wondering, how it knows to get the information in the first place. there is another protocol SLP (Service Location Protocol) which advertises to your computer enough information that it can get the rest of the information from the DHCP server. I hope this was helpful