Networking - Networking Basics - Discussion

Why can't NAT?

I don't understand, Please explain.

Network address translation (NAT) is a router function that enables public and private network connections and allows single IP address communication. While there are many public networks worldwide, there is a limited number of private networks.

NAT is static network address translation that is used to convert one IP private of local translate into public one ip address private allow many users to connect to the global internet.

PAT:-is dynamic port address translation that is used to convert multiple ip private to public IP address.

Multiple IP address privates allow many users to connect to the global internet.

What are PAT and NAT? I want a clear explanation.

Network Address Translation (NAT) and Port Address Translation (PAT) both map IP addresses on an internal network to IP addresses on an external network. Which method of address translation you use depends on the types of networks that you are translating and the number of available IP addresses that you have.

If you are connecting a site to the 10.10.10.0 network to a site in the 10.10.20.0 network, you could use NAT to translate 10.10.10.0 IP addresses to available 10.10.20.0 IP addresses so that hosts on the 10.10.10.0 network can access data and use network resources on the 10.10.20.0 network. However, for this scenario to work, you must have an address pool that contains enough available IP addresses on the 10.10.20.0 network to accommodate every host on the 10.10.10.0 network, because NAT requires a one-to-one relationship when translating IP addresses.

PAT attempts to use the original source port number of the internal host to form a unique, registered IP address and port number combination. For example, two hosts that have been assigned the IP addresses 10.10.10.100 and 10.10.10.101, respectively, could send traffic to and receive traffic from the Internet by using the single public IP address 123.45.67.89. If that port number is already allocated, PAT searches for an available alternate source port number. Therefore, the host at IP address 10.10.10.100 could access the Internet by using the public IP address and source port combination of 123.45.67.89:10000. Meanwhile, the host at IP address 10.10.10.101 could access the Internet by using the IP address and source port combination of 123.45.67.89:10001.

Static NAT (Network Address Translation) - Static NAT (Network Address Translation) is a one-to-one mapping of a private IP address to a public IP address. Static NAT (Network Address Translation) is useful when a network device inside a private network needs to be accessible from the internet.

Dynamic NAT (Network Address Translation) - Dynamic NAT can be defined as a mapping of a private IP address to a public IP address from a group of public IP addresses called as NAT pool. Dynamic NAT establishes a one-to-one mapping between a private IP address to a public IP address. Here the public IP address is taken from the pool of IP addresses configured on the end NAT router. The public to private mapping may vary based on the available public IP address in NAT pool.

PAT (Port Address Translation) - Port Address Translation (PAT) is another type of dynamic NAT which can map multiple private IP addresses to a single public IP address by using a technology known as Port Address Translation.

Here when a client from inside network communicate to a host on the internet, the router changes the source port (TCP or UDP) number with another port number. These port mappings are kept in a table. When the router receives from the internet, it will refer the table which keeps the port mappings and forward the data packet to the original sender.

It should be Static.

What is pat? explain.

Please give practical application for NAT and PAT.

What are the uses of Port Address Translation (PAT)?