When it comes to maintaining a secure LAN environment in an organization’s IT system, the terms proxy and NAT are frequently employed.
A proxy (proxy server) is a server that acts as a mediator between a client and another server.
When a client requests help, the proxy server connects to it and examines the request using its filtering rules.
The act of changing the IP address in the header of an IP packet as it goes through a routing device is known as Network Address Translation (NAT).
With NAT, you can use one set of IP addresses for traffic inside your LAN. You can also use another set of IP addresses for traffic outside your LAN.
The most straightforward kind of NAT provides a one-to-one translation of IP addresses.
What Is a Proxy?
Proxy is a Layer 7 solution that can inspect requests more thoroughly. It also provides features such as caching and filtering (either policy or virus screening). It can also hide the original request’s originating address.
Although there are several hacks to set up “Transparent” proxy settings, a proxy server requires the client type to be configured to use the proxy.
It tends to function better if the client knows it is intended to use the broker.
Proxies can have up to 7 layers:
- Layer 1 – Physical: physical components such as cable wire and Wi-Fi are included in this layer.
- Layer 2 – Data Link
- Layer 3 – Network: IP and OSPF are network routing protocols.
- Layer 4 – Transport: data transmission protocols
- Layer 5 – Session: methods for setting up point-to-point communication
- Layer 6 – Presentation: character encodings
- Layer 7 – Application: application protocols
Finally, while running at Layer 7, you’ll need a different proxy for each protocol you wish to proxy.
But, the proxy can fulfill the client’s request without contacting the original server. The proxy employs a cache to do this.
Any other requests for the same resource are fulfilled without visiting the specified server.
As a result, high-speed datacenter proxies can boost performance dramatically. Proxies can also filter requests and block access to specific websites.
What Is NAT?
NAT is a Layer 3/4 solution created as a workaround for IP addresses.
It was never intended to be used as a security or proxy solution. All it does is change one of the packet’s addresses.
Then it keeps note of which streams (and related packets) have had NAT applied. That can “undo” the address substitution on the return packets.
Clients do not need to be configured for NAT to establish the proper gateway in the routing table.
Because NAT operates at Layers 3 and 4, it may be used on any IP connection, independent of the higher protocols. However, it may disrupt some less prevalent protocols.
There are various advantages of using NAT. Because it allows internal IP addresses to be hidden, it increases the security of a local network.
Difference Between Proxy and NAT
· Target solution
Proxy is suggested for corporations with a large user base. NAT is recommended for businesses with a low user population and low traffic.
When a proxy is combined with NAT, you can create target solutions for specific problems regarding network configuration.
· Cost
A proxy is expensive because a separate proxy device is required to execute the functionality.
On the other hand, NAT is inexpensive and does not require a different NAT device. Any layer 3 or above device, such as a router or firewall, can execute NAT.
· Key functions
Proxy gives end hosts safe access to Internet-based applications. Proxy servers translate traffic between networks or protocols.
These are intermediate servers that are isolated from the destination that references the end-user client.
Proxy servers provide varying levels of functionality, privacy, and cybersecurity.
It all depends on your application, requirements, or company guidelines.
However, NAT protects the device’s IP address by hiding it as traffic flows through the network.
Using the IP masquerading procedure, NAT hides the device’s IP address. As your network evolves, you no longer need to renumber your addresses.
Maintaining the number of public addresses in your organization has important uses in firewall security.
· Key benefits
Proxy improves security and gives you control over how much access your system has to the outside world.
Proxy servers also allow users to bypass content restrictions imposed by businesses or governments.
To help with the IP address scarcity, NAT hides a lot of private IPs behind a smaller number of public IPs.
· End host configuration
In the event of an explicit proxy, it may be necessary to configure the destination host. The end host system may not need to be configured for transparent proxy.
NAT does not need to be configured for the end host system.
· NAT/Proxy device visibility
Proxies operate as middlemen between two devices, with both ends aware that they are communicating with the proxy.
While with the NAT device, the two communicating parties are unaware of a NAT device in the middle.
· Traffic flow
With proxies, the source system transmits traffic to the proxy with its source IP and the proxy’s destination IP.
The proxy starts a new session with its IP as the source and the distant Server’s IP as the destination.
However, the source machine (with a private IP) delivers traffic to the remote server destination using NAT.
The NAT device translates the source/destination personal IP address to a public IP address and transfers it to the distant server.
· Application requirement
The proxy does not need any specific application software to function.
However, NAT applications behind a proxy server must support proxy services. You must configure them to utilize the proxy server.
· Overhead
Because each packet is inspected and then taken in proxy, there is a relatively high crowd.
However, NAT is a lot easier and has a lot less overhead.
Conclusion
Proxy and Nat are both very similar when it comes to why people use them. NAT operates on a more fundamental level than normal proxy systems. Proxy server solutions are often protocol-specific, supporting just certain application layer protocols.
A proxy server connects to, replies to, and receives internet traffic on behalf of the client computer, whereas a NAT device alters the originating address of traffic arriving via it before delivering it to the internet.
