Why are Stateful Packet Inspection Firewalls Inexpensive?
Stateful packet inspection firewalls are inexpensive because they use a connection-oriented protocol to make decisions on packets. This means that the firewall can store information about an established TCP or UDP session and assign it one of three states – create, maintain, or delete. An inbound packet will be matched against these rules for its destination address, source address, service type (e.g., SSH), and port number before being either allowed or denied access to the network behind the firewall.
How does the stateful packet inspection system work?
Stateful packet inspection firewalls work by inspecting data that is transmitted between endpoints and storing information based on the protocol. This means that if a user tries to connect to their email server, your organization’s SPAM filter can be disabled temporarily because it will not see any packets coming from the user’s mail client because the firewall will only work on packets that are inbound to your organization. This can be a major security flaw, but is generally desirable from an overall cost perspective when compared with stateless packet inspection firewalls which require significant processing power and memory resources.
Why is it important to have a stateful firewall?
Stateful firewalls are important because they use TCP and UDP port information in their security decision-making processes. This means that if an attacker knows your network’s protocols, then the protocol stream will be able to be deciphered by attackers who know what ports should exist for that particular type of traffic. This information can be used to launch attacks against your network. So in order to prevent your network from being compromised, it is important to have a stateful firewall.
Stateful packet inspection firewalls are important because they can help protect your organization from security issues and reduce costs. While stateful packet inspection firewalls do not provide the same level of protection as a stateless firewall, they are easier to configure and less expensive. This makes them an excellent choice for organizations looking to secure their network but can’t afford or don’t need a more comprehensive solution.
Why a stateful packet inspection firewall is less susceptible?
The working of a stateful packet inspection firewall is less susceptible as compared to the other firewalls. A stateful packet inspection firewall stores information about the session and uses this as a reference point for future packets. This allows it to detect abnormal traffic patterns, such as port scanning or an attack on one host that spreads across the network, which is often used by attackers looking to compromise systems without being detected.
What is the difference between a stateful inspection firewall and a packet filtering firewall?
A stateful inspection firewall differs from a packet filtering firewall because it uses session information to make security decisions. This means that if an attacker knows your network’s protocols, then the protocol stream can be deciphered by attackers who know what ports should exist for that particular type of traffic. A packet filter does not have this capability and will only inspect the data that is transmitted. This makes it easier for an attacker to launch a successful attack against your network as they can easily determine the ports needed and use those ports in their future attacks, whereas stateful inspection firewalls do not provide this information.
What are some of the common types of attacks made possible by packet filtering firewall?
Some of the common types of attacks made possible by packet filtering firewalls are:
IP spoofing – where a source address is faked to allow an attacker to masquerade as another machine
DoS/DDoS – many modern-day attackers utilize distributed denial-of-service (DDoS) attacks which can be launched from within your network without being detected. This occurs when a system is overwhelmed with traffic from outside sources, causing it to become unavailable
Buffer overflow – where an attacker attempts to overrun the memory of a networked machine in order to gain control over that system. With this type of attack, they are attempting to cause the server or client program on your network to crash or run arbitrary code.
What are some of the common types of attacks made possible by a stateful packet inspection firewall?
Some of the common types of the attack made possible by a stateful packet inspection (SPI) firewalls are:
Man in the middle – where an attacker intercepts and monitors traffic between two systems. This can allow them to steal information such as credit card numbers, passwords, and other sensitive data
Man in the browser – where an attacker injects malicious code into a web page or form that is then run by your networked system. This allows them to gain access to information such as cookies which can be used for session hijacking – taking over someone’s existing authenticated session with their provider or network
Phishing – where an attacker attempts to fool a user into providing their personal information such as credit card numbers, passwords and other sensitive data by using fraudulent email messages or websites that look like legitimate sites. If the user provides this information, it is then used for identity theft purposes.
Conclusion:
An SPI firewall provides you with the best defense against these types of attacks and is highly recommended. It allows system administrators to monitor activity, create alerts when unusual traffic patterns occur and quickly stop any attempts at unauthorized access which can be vital in keeping your network secure.
