NAT benefits and drawbacks

Network address translation (NAT) is used by client systems to be able to browse the web using the public address ICS computer under a masked TCP/IP address. This is because internet hosts only see public addresses. The internal structure of the network is actually hidden from the public eye by adding a layer of protection against hackers or others who try to penetrate your system.
Even though NAT has the ability to hide the internal structures of the internet, it only makes the situation more difficult on hackers to breach a system. This should not be the only sole device used for protection against unwanted outside views of your network. Firewalls and intrusion detection systems (IDSs) should also be implemented on your network to help protect against any intrusions.
NAT modifies network addresses and the packet headers which carry through the network as they are being sent. They are remapped while they travel from one routing device to another making it safe to travel on the net.
Setting a static NAT allows the origination of traffic on the outside of a network to reach its destination host. Masqueraded networks completely hide the address space which any given private network has and gives it a public address space. This is done with a device known as a router. These rewritten addresses are translated and are given a single IP address by the router so that the packets that exit the device only shows the IP address of the router and not the original private address of the network. When these packets are reversed and sent back, they are re mapped back to the original IP address stored in the translation tables. The translation table has rules on how it refreshes and flushes its data without outside traffic having to refresh as well.
There is though however drawbacks as well as benefits on the translation of network address which affect the quality of connectivity over the net. NAT is a popular tool and has become the standard in routers for not only home offices, but small offices on internet connections. In the United States, NAT is the main standard for network address translation.
Multiple hosts on any given private network that has access to the internet can use a single IP address that is public which is also known as gateway. But NAT has an impact on how it breaks the original IP from one end to another which produces some complications between hosts. This also causes some performance impacts on the network.
The internal structure of a network is obscured by the NAT and all traffic appears to originate from a single outside gateway machine. The translations of IP addresses is re-written and so is its source and original ports from which packets where sent from. This causes checksums of the IP and TCP to be also rewritten to mach the changes.
One of the biggest drawbacks of NAT enabled routers is that they do not have end to end connectivity. The routers cannot use all internet protocols as well as routers that are not NAT enabled. Protocols such as UDP can be disrupted when services are activated that require the initiation of TCP connectivity from an outside network. Unless the NAT routers are made to accommodate special effort to support these protocols, they won�t reach their destination. FTP is a protocol that can effectively work within the NAT router with some assistance of another protocol called Application Layer Gateway. These sometimes fail through the internet when they are separated by NAT. Tunneling Protocols can also be effected and complicated because NAT modifies a headers value.
The primary core of the internet is the end to end connectivity and the NAT can be a disruption to this principle. NAT however does have important roles in careful design. IPv6 NAT and its architects show that the need for NAT can be removed. Most ISPs give their customers access to the internet with a local IP address which is networked through a NAT enabled router. It is being argued that the customers truly are not being provided internet service.
Some look at the NAT being a convenience because of its low cost and lack of end to end connectivity. To some point, NAT enabled routers depend on a local machine on the network to connect to a host on the other side of the router. This essentially prevents viruses that originate from the host on the outside of the network. Even though this may be true, the use of a firewall also can be implemented for the same benefits of a NAT enabled router.

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