What is the purpose of the Domain Name System (DNS)?
4.
Describe a DNS lookup process.
5.
List three advantages of using a DHCP server on your network.
6.
How do you find a rogue DHCP server on your local subnet?
7.
If your users require more than one IP address, what would you do?
Answers
1.
An IPv6 address consists of eight 16-bit numbers (128 bits). The first four numbers contain network and subnet information. The last four numbers form the address of the network interface on a network device.
2.
IP over FireWire is suitable for networking and clustering solutions.
3.
The purpose of DNS is to perform IP address-to-name and name-to-IP address resolution for computers on the Internet.
4.
A computer running Mac OS X uses lookupd to locate the name of its own domain and the IP address of its name server. The computer makes a system call to named on the DNS name server to perform the IP address-to-name translation. If the name server has the authority (names and IP addresses are stored on it for the resolution requested), it responds to the request by the DNS client. If it does not have the authority, it checks its cache to see whether the name was resolved recently. If the name was resolved recently, the server reports the caching information to the client. If the resolver does not have the authority for the name or have it stored in its cache, it directs the request to the root server of the global DNS system for a top-down search.
5.
Automatic IP address assignment, reclaims unused addresses, and avoids UIP address conflicts.
6.
To find a rogue DHCP server on your local subnet, use the getpacket option of the ipconfig command to get the IP address of the rogue DHCP server. Then use the arp -a command to find the MAC address that corresponds to the IP address of the rogue server.
7.
Use multihoming to configure more than one IP address for each network interface. In the Network pane of System Preferences, you can choose active ports, add a new port, and configure a port with a new IP address.
