Difference Between a Proxy Server and Packet Filtering Firewall
A proxy server and a packet filtering firewall, to someone with a moderate level of know-how about network security, might confuse the two terms. There are many similarities between these two devices but when it comes to their functions there are some very important differences.
In this blog post, we will discuss the difference between a proxy server and a packet filtering firewall so you can determine which one best suits your needs.
How Does A Proxy Server Differ From A Packet Filtering Firewall
A Proxy Server is a computer system or program that acts as an intermediary for requests from clients seeking resources from other servers. Whereas,
A Packet Filtering Firewall is a device, usually located at the entry point to an organization’s network, which examines each incoming packet and blocks those packets that do not meet predetermined criteria.
| Proxy Server | Packet Filtering Firewall | |
| Connect external client with a server | ✔ | 🗙 |
| Works on application layer data | ✔ | 🗙 |
| Monitor and filter all the incoming and outgoing traffic on a given local network | 🗙 | ✔ |
| Facilitate connections over a network | ✔ | 🗙 |
| Overhead generated is more | 🗙 | ✔ |
| Filter data by monitoring IP packets that are traversed | 🗙 | ✔ |
Packet Filtering Firewall
A packet filtering firewall is typically used to monitor traffic on a network, allowing or disallowing packets through its rules based upon the information within each packet and configured rule set for that specific device. Some of these conditions can be source/destination IP addresses, protocols (such as TCP vs UDP) port numbers, protocol type (such as TCP vs UDP), and source/destination port numbers.
Proxy Server
A proxy server, outside of simply blocking unwanted content, can also cache requests so frequently requested data doesn’t need to be loaded repeatedly. It may also compress information before sending it across the Internet to speed up page load time. A proxy server also provides increased security by hiding the IP address of a computer on your local network, making it more difficult for snoopers to gain access.
How Do Proxy Server And Packet Filtering Firewall Work Together?
When implemented together, these devices can create a secure network capable of preventing unauthorized access to both your Internet connection and any private resources connected to it.
A proxy server can be used at any point in your network which makes it ideal for protecting computers on the edge of your local area network (LAN) while allowing you greater control over how traffic is filtered throughout. Because this device is capable of filtering packets at the application level, it can protect your entire network.
A packet-filtering firewall can be used in conjunction with a proxy server (or even another packet filtering firewall) for security purposes. While not as robust when it comes to content inspection or control over how traffic is filtered throughout your network, this device excels at blocking unauthorized requests and viruses from entering through its port-based system.
Advantages And Disadvantages Of Using Packet Filtering Firewall And Proxy Server
Packet Filtering Firewall
| Advantages | Disadvantages |
| A packet filtering firewall is easy to set up and maintain. | When creating packet filter firewall rules you must specify all components involved for them to work properly including source, destination, port number, transport protocol type (TCP / UDP), etc. |
| It can be used on its own for basic security purposes or in conjunction with other firewalls, proxy servers, routers, wireless access points (WAPs), VPN concentrators, intrusion detection systems (IDSs), and more. | Rules cannot reference packets based on their content which makes this device less effective at stopping specific threats like viruses and malware. |
| This device does not require additional software that acts upon specific content so it’s ideal for situations where organizations want to monitor traffic without slowing down their networks. | While these devices are capable of fending off many kinds of network-based intrusions they have a harder time defending against application layer protocol exploits or operating system vulnerabilities that come from within your own network. |
| Packet filters are also commonly employed at the entry point of an organization’s network which helps prevent unauthorized access from outside sources. | Some of the most common types of packet filter firewall attacks include IP spoofing, TCP SYN floods, UDP floods, ping of death attacks (PODs), and smurf attacks. |
| It uses rules-based enforcement rather than user accounts or applications to control what gets filtered through your network. There are no limitations on what time of day or how often a rule is triggered. The addition of new rules requires only the click of a button and there are no additional licenses required to add more features. | |
| This device can be configured for passive operation which allows it to monitor traffic without responding in real-time. This means that if an unauthorized request does get through, this device will not respond until the next scheduled cycle so normal network performance isn’t impacted by its presence |
Proxy Server
| Advantages | Disadvantages |
| Proxy servers excel at filtering web traffic by passing requests through to an upstream server before returning it down to the client destination for processing. This is why proxy servers are often used as a method for speeding up access to Internet resources that are hosted on a server that may be located further away from the client. | Proxy servers make it easier for attackers to hide their origin by routing traffic through one or more intermediate points before reaching its destination. This makes this device less effective at filtering out malware and viruses because they can get past your security measures without being detected even if you have anti-virus software installed on each of your devices. |
| Unlike packet filtering firewalls, proxy servers are capable of inspecting the contents of requests and responses to ensure that they meet acceptable security policy requirements. | When creating filter rules for proxy servers, modifications must be made in real-time to match requests with specific IP addresses or domain names within URLs before forwarding them along to an upstream webserver. If these changes aren’t implemented quickly enough then clients will receive errors when attempting to access restricted resources until new rules are created and implemented |
| This device is also typically configured with its own authentication system or can be used in conjunction with existing infrastructure like Active Directory (AD) for stronger user access control. |
Conclusion
There are many similarities between these two devices but when it comes to their functions there are some very important differences. While both can be used to prevent unauthorized access, a packet filtering firewall is typically employed at the entry point of an organization’s network while a proxy server may exist on any computer in your network.
Proxy servers are capable of performing several functions that go beyond simple packet filtering While both devices can be used for security purposes they each excel at different tasks which makes them useful in different situations. To determine if either device is right for your needs you should carefully consider how it will benefit your network before purchasing one or the other.
If increased security is what you need then a proxy server may best suit your company.
But if simplicity is key, implementing a packet filtering firewall would probably make more sense instead.
When securing the devices that are situated between your users and servers, it’s important to understand their unique strengths so you can configure them in a way that maximizes security without interfering with network performance.
Utilizing multiple layers of protection allows organizations to reduce risk while increasing productivity for employees who need remote access from outside sources.
