Understanding IPv6, Client/Server, DNS, IP, and NAT
How IPv6 Works
- IPv6 has more address space because it uses 128 bits, whereas IPv4 uses only 32 bits for its IP address.
- IPv6 gives more quality for some applications, such as live video and phone calls, as it can give high priority for some packets.
- IPv6 also has more security options.
How Client/Server Architecture Works
The client sends a request for a specific web page or a database search, using TCP/IP. The request is broken into HTTP packets to the host computer (for example, a Google server). The server software will search for this information and send it back to the client via TCP/IP protocols.
Understanding Internet Addresses and Domains for Email
For example, in an email address, “hamad” is the first part, which is to the left of the @ sign, and refers to the user of the account.
The second part, to the right of the @ sign, contains the hostname (capital), which refers to a specific server, and the domain name (gov.bh).
The domain name system divides the internet into understandable groups, such as “gov” for government and “edu” for educational organizations.
Domain name servers change the address from alphanumeric to numbers, such as 127.27.456.72, so the internet can understand it. Addresses are made alphanumeric because they are easier to remember.
How Domain Name System Servers Work
When a web browser tries to connect to a URL, my web browser asks the local name server about the IP address. If the IP address is a local one on my network, the local name server will send the IP address to my computer.
If the IP address is not on my local server, the local name server will connect to the root domain server, which will guide it to the primary and secondary name servers and pass the IP address to the local name server and then to me.
How Static and Dynamic IP Addresses Work
When you connect to the internet, your computer must be identified by an IP address. There are two different methods for assigning IP addresses: statically or dynamically.
Static IP address: Your computer keeps the same IP address every time you connect to the internet.
Dynamic addresses: Are assigned every time you connect to the internet.
- To get a dynamic IP address, your computer sends a broadcast message asking for an IP.
- The message is received by the DHCP server. The DHCP server checks the list for available IP addresses and sends you one.
- Your computer will receive the offer and will send back a DHCP request to the server.
- The DHCP server will receive the request and will send you a DHCP pack.
- Your computer can now use the IP address.
How Network Address Translation Works
Computers need unique IP addresses on the internet, but there are not enough IP addresses for all the world’s computers. That’s why we use Network Address Translation (NAT).
NAT is a process done by the routers. A router has its own IP address, and this IP is visible on the internet.
Each computer on the internal network gets an internal IP address from the router.
This internal IP address is not visible. On the internet, they only see the router’s IP for all the computers on the internal network.
NAT helps to protect computers from hacker attacks because the IPs are hidden.