What is the Best Spam Protection?

The so-called spam firewall is a dedicated mail server that forwards mail to and from your internal mail server.

Internet spam has caused us great harm, wasting a lot of network resources and wasting our precious time. Network viruses and spam are always the two main aspects of network security. At present, there are many kinds of spam solutions, but there are four main types: software solutions for clients; remote email filtering services; enterprise-level software solutions; hardware devices.

The client software solution is to install software. The current anti-spam software is scattered, especially in China. Whether it is the personal or server version of anti-spam software, it is more from the hands of some individual developers. Among them, The definition of spam is inaccurate, and many people define spam as a virus. Spam emails are mainly classified into advertising emails, anonymous harassing emails, and fake emails. At present, the software mainly uses filtering based on the sender address, email subject, or email size. But on the one hand, because of the random randomness of spam, it is difficult to grasp the accurate characteristics of spam. On the other hand, due to the misunderstanding of most anti-spam tools themselves, it is difficult to completely prevent spam. At the same time, for a large enterprise, it is difficult for an anti-spam software to hold thousands of all kinds of spam messages every day.

At present for enterprise users, most use advanced hardware firewalls, and individual users use software firewalls. Compared with software firewalls, what are the advantages of hardware firewalls? Hardware firewalls use dedicated hardware equipment, and then integrate the manufacturer's dedicated firewall software. From a functional point of view, the hardware firewall has built-in security software and uses a proprietary or enhanced operating system for easy management and easy replacement. The hardware and software are relatively fixed. The hardware firewall has high efficiency, resolves the contradiction between the efficiency and performance of the firewall, and can reach linearity.

Software firewalls are generally developed based on an operating system platform, and software is installed and configured directly on the computer. Due to the diversity of customer platforms, software firewalls need to support multiple operating systems, such as

The SMTP protocol itself is a simplified mail delivery protocol and lacks many necessary authentications. This is

Here are the protection technologies used by this anti-spam firewall:
1 Denial of service attack and security protection 2 IP block list 3 Rate control 4 Double-layer virus scanning 5 User-defined rules 6 Spam fingerprint check 7 Email intent analysis 8 Bayesian intelligent analysis 9 Rule-based scoring system Virus protection Because rate control, virus scanning, and virus protection of decompressed files are aimed at viruses, they are a subsidiary function of anti-spam. We will not discuss them for the time being. It is worth mentioning that the firewall to prevent DDOS attacks and the anti-spam firewall to prevent DOS attacks Different. According to the technical engineer of Bo Witt: The anti-spam firewall's prevention of DOS attacks mainly prevents sending a large number of spam emails to a mail address within a short period of time, thereby forming a Dos attack.
The core technologies for spam include Bayesian intelligent analysis, spam fingerprint check, rule-based scoring system, and user-defined rules. The core of these technologies are Bayesian intelligent analysis and spam fingerprint check technology.

A firewall is a broad term. From the perspective of practical applications, a firewall is a protective device to protect internal network resources (such as www servers, file servers, etc.) from external security threats. By setting different protection levels and protective measures, Implement protection for internal network resources. Depending on the focus of protection, firewalls can be divided into virus firewalls, DDOS (distributed denial of service attack) firewalls, spam firewalls, and so on.
In short, an anti-spam firewall is a dedicated firewall for anti-spam.
Firewalls have one thing in common in terms of how they work: they analyze the packets going in and out of the firewall, and decide whether to pass or block. In actual deployment, as a dedicated spam firewall, it can be placed in front of the ordinary firewall or behind the firewall. It is recommended that it be logically maintained in series with the mail server.
a) The MX record must be modified (or added) when installed outside the firewall. The MX record can point to the anti-spam firewall. If there are two, the MX record pointing to the anti-spam firewall has a higher priority. .
b) Install in the firewall to point the SMTP NAT record to the anti-spam firewall. In both cases, no changes need to be made in the server and client software (outlookfoxmail, etc.)