The process of determining an address given a name is called name resolution. When someone types a name like www.mydomain.com into a web browser address line, the system will need to translate this into an IP address and finally determine a MAC address to put in the Ethernet frame. The process looks link this;
Domain name è IP address è MAC address
www.teamapproach.ca è 22.214.171.124 è 00-10-5A-A7-33-03
By default, Windows will simply send out broadcasts to resolve computer names. This is the least efficient way to do name resolution because a broadcast interrupts every computer on the subnet. It is the default because it needs no configuration and no server is required.
WINS and DNS
name query request = What is the address for Joe'sComputerè
To reduce broadcast interrupts, Microsoft computer names can be resolved with a WINS Windows Internet Name Service Server. Internet domain names can be resolved by DNS servers. WINS provides compatibility for older versions of Windows. WINS and NetBIOS computer names are no longer necessary in Active Directory environments. Active Directory replaces WINS with DNS.
name query request = What is the address for www.joe.comè
Windows clients can be configured to use different kinds of resolution techniques to resolve Microsoft computer names. The registry configuration is NodeType REG_DWORD at HKLM\SYSTEM\CurrentControlSet\Services\Netbt\Parameters.
ARP Address Resolution Protocol
request broadcast - Which machine has this IP address?
The IP address to MAC address resolution is done with ARP Address Resolution Protocol. When a machine wants to communicate with an IP address, it must determine the hardware MAC address (e.g. Ethernet). This is done by sending out an ARP request broadcast which contains the destination IP address. This interrupts every machine in the subnet, but only the machine with the IP address will respond.
The address information is cached temporarily. The cache can be viewed with the command ARP -a. The following is example output of the ARP -a command.
Interface: 0.0.0.0 --- 0xffffffff
The longer entries stay valid in the ARP cache, the fewer broadcasts are required to rediscover the addresses. For better performance, increase the ARP cache life time by using the Registry Editor. The entries to consider are
DHCP Dynamic Host Configuration Protocol
IP addresses can be assigned to network interfaces by using the Control Panel. This can be rather tedious if you manage many computers. Windows Servers have a DHCP service that can automatically assign IP addresses and configuration to each computer. DHCP clients must initially send out a broadcast to find a DHCP server.
there any DHCP servers that can assign IP configuration?
DHCP assigns the address for a period of time known as a lease life. Half way through the lease life, the client requests a renewal of the lease. By default, the lease life is