Proxy Firewall: An Enhanced Level of Security

Limiting or preventing connections to or from a network is the common objective of both firewall and proxy servers. They both reside between the local computer and the network and offer security against network threats. 

 

Network security includes both a firewall and a proxy server. They do this in various ways, but they are somewhat similar in that they restrict or prohibit connections to and from your network. 

 

While proxy servers essentially conceal your internal network from the Internet, firewalls can block ports and programmes that attempt to reach your computer without authorization. It functions similarly to a firewall in that it prevents your network from being exposed to the Internet by rerouting Web requests as needed.

 

A Proxy Firewall: What Is It?

 

The most secure type of firewall is a proxy firewall, which guards network resources by filtering communications at the application layer. A proxy firewall, often referred to as an application firewall or a gateway firewall, restricts the kind of applications that a network can handle, raising security levels but at the risk of slowing down functionality and performance.

 

Traditional firewalls are not made to inspect application protocol traffic or decrypt traffic. To protect themselves from threats, they often utilize an intrusion prevention system (IPS) or antivirus programme, but they only cover a small portion of the threat environment that enterprises currently confront.

 

In order to safeguard data entering and leaving a network, a proxy server acts as a gateway or middleman between computers and servers on the internet. 

 

A proxy server chooses which traffic should be permitted and which should be blocked and examines incoming traffic to look for indicators of malware or future cyberattacks. To protect networks from hackers and unauthorized users, a proxy server firewall caches, filters, logs, and limits requests from devices.

 

How the proxy firewall responds to internal network requests :

 

1. The proxy firewall serves as a bridge between a secure internal network and the public internet.

 

2. Computers in internal networks must first communicate with the proxy in order to connect to the outside internet.

 

3.  The proxy then sends data received from the internet to the internal network and forwards data from the internal network to the internet.

 

4.  By preventing direct connections between the internal network and the internet, the proxy firewall protects the internal network from outside internet invaders.

 

Operation of Proxy Firewall

 

The most secure firewalls are proxy firewalls, but they sacrifice speed and functionality since they can restrict the types of applications that your network can serve.

 

Information packets do not flow through a proxy, in contrast to other types of firewalls, giving proxy firewalls increased security. Instead, the proxy serves as an intermediate, allowing computers to connect to it and then request a new network connection, thereby mirroring the information flow. 

 

As a result, it is more difficult for hackers to determine the location of the network from packet information since direct connections and packet transfer between the firewall's two sides are prevented.

 

A firewall proxy gives computers on a network access to the internet, but it is typically used to control the information entering and leaving the network to ensure safety or security. To keep the network safe and virus-free, firewall proxy servers filter, cache, log, and control requests originating from a client.

 

Proxy servers are essentially gateway programmes used to direct internet and web access from behind a firewall. By opening a socket on the server and enabling the connection to pass through, proxy servers function. 

 

In a proxy firewall network, there is frequently just one computer with a direct Internet connection; other computers access the Internet by utilizing that computer as a gateway. When a client inside the firewall sends a request, a proxy gateway forwards it to the remote server outside the firewall. 

 

The client is then provided a response from the server after reading the response. All client computers in a network often utilize the same proxy, allowing the proxy to effectively cache documents that are requested by several clients.

 

Also Read | A Complete Guide to Information Security

 

 

What Kind of Work Does a Proxy Firewall Do?

 

Unlike other kinds of firewalls, a proxy gateway increases security because data packets do not pass through it. Instead, the proxy acts as a middle layer, allowing computers to connect to it, which then creates a new communication link in response to the request, reflecting the data flow. 

 

By doing away with direct connections and packet transfer, hackers will have a harder time figuring out the network's address from packet data.

 

A proxy firewall enables networked devices to access the internet. The primary function of a proxy firewall is to provide system security by controlling the material that enters and leaves the system. Firewall proxy servers examine, store, monitor, and manage user requests in order to keep the network secure and free of viruses and attackers.

 

Programs called proxy servers are used as barriers to reroute web and technology traffic. Proxy servers work by allowing a link to pass through a server port. The lone computer with a constant Internet connection is typically the gateway through which other devices connect to the internet. 

 

A proxy gateway receives a request from a client inside the firewall and transmits it to an external remote computer. Instead, the user receives and receives the server's response.

 

Proxy Firewalls: How Do They Work?

 

Proxy firewalls provide comprehensive, methodical security evaluation for the networks they manage. Compared to solutions that only rely on packet headers, they can provide significantly better security advice at the application layer.

 

Proxy firewalls mask the structure of the inside protected network. Private IP addresses are concealed from the general public as a result of proxy services that restrict direct communication between local devices and remote servers. Proxy firewalls carry out this function by default, though Network Address Translation (NAT) techniques may be used.

 

Network detection is much harder since hackers do not obtain signals produced by their target systems. Hackers may routinely gain considerable knowledge about the kind of physical hosts present on a system by regularly monitoring incoming packets of data from addresses. 

 

By examining how systems administration configures data like the Time to Live (TTL) parameter, window size, and TCP settings, a hacker can determine which operating system is used on a server. 

 

This method, known as fingerprinting, is used by the hacker to determine the kind of assaults to use against the client application. Firewalls can stop a large portion of this activity since the attacker's machine does not receive any information packets created by the host.

 

Also Read | What are Ethical Hackings and Its Phases?

 

Advantages of Proxy Firewall

 

Proxy firewalls have a number of benefits over other kinds of firewalls, including:

 

1. For the protocols they support, proxy firewalls provide thorough, protocol-aware security analysis. They are able to make better security decisions than devices that only consider packet header data since they operate at the application layer.

 

2. Proxy firewalls conceal the topology of the internal protected network. Proxy services prevent direct connections between external servers and internal systems, hiding internal IP addresses from the outside world. Although network address translation methods can also be used to do this, proxy firewalls already do it.

 

3. Because attackers do not directly receive packets produced by their target systems, network discovery is made noticeably more challenging. Attackers frequently use packet header information from the hosts to gather specific information about the types of hosts and services present on a network. 

 

An attacker may use the settings for the Time to Live (TTL) field, window size, and TCP options to identify the operating system being used on a server. 

 

An attacker uses this method, called fingerprinting, to decide what kinds of attacks to use against the client system. Because the assaulting machine doesn't receive any packets that the server directly creates, proxies can stop a large portion of this activity.

 

4. In proxy firewalls, robust, protocol-aware logging is possible. This can make figuring out an attack's tactics a lot simpler. Additionally, it offers an important backup of the server logs that the proxy is protecting.

 

Disadvantages of Proxy Firewall

 

Proxy firewalls can offer more protection than packet-filtering firewalls, but they can have drawbacks. Before setting up a proxy firewall, you should keep in mind these disadvantages of proxy firewall : 

 

1. Not all network protocols are compatible with proxy firewalls. For any new application or protocol that needs to flow past the firewall, a new proxy agent needs to be created. You might have to settle for a generic proxy if the proxy product you select does not support a necessary protocol. If the protocol is nonstandard, even generic proxies might occasionally fail to function.

 

2. The additional processing requests necessary for application services lead to a decrease in performance. There are no free meals in life. Slower performance is caused by the additional expense entailed by opening two connections for each discussion as well as the time required to validate requests at the application layer. 

 

In some circumstances, you can strike a balance by running your proxy on more powerful servers. However, a proxy firewall could constitute a performance stumbling block for some networks with excessively high bandwidth.

 

3. A proxy firewall may prevent Virtual Private Networks (VPNs) from operating. As will be covered in more detail in Chapter 7, "Virtual Private Networks," VPN packet authentication will be unsuccessful if the sender's IP address is changed while the packet is being transmitted. 

 

The similar problem exists with proxy firewalls, despite the fact that network address translation is typically assumed to be the culprit here. Of course, this won't be an issue if the firewall serves as the VPN endpoint.

 

4. Compared to other firewall technologies, proxy firewall configuration can be more challenging. It might be challenging to correctly install and configure the set of proxies required for your network, particularly when utilizing older proxies.

 

Also Read | Network Security: Types, Advantages and Disadvantages

 

 

Firewall and Proxy Servers

 

1. For outgoing HTTP messages to the Internet, your network can also need a proxy server. On your partner's network, a proxy server could be required for your messages to pass through.

 

2. Although all proxy servers and firewalls are proxy servers, not all proxy servers and firewalls are proxy servers. They each operate as a mediator between servers and their respective clients. 

 

The two programmes can both keep user information secret from the server and can both cache web pages to lessen network congestion. Network traffic is put through a more thorough analysis using a proxy firewall to find and block possibly harmful traffic.

 

When deciding which firewall to use, take into account the following aspects: the size of the company, the resources at your disposal, and the necessary level of security.