web filter

•  Unfortunately, some of those sites had malware that could infect the browsing

computer. Or, sometimes a website contained content that others objected to. What

constitutes objectionable content can be controversial, but these two reasons—Security and

Objectionable content—formed the impetus for the development of web filtering technology. 

What is a web filter? It’s an application that examines incoming webpages to determine if

some or all of the content should be blocked. The web filter makes these decisions based on

rules set in place by the organization, or individual, who installed the application

browsing was made safer by

developing filters that could block adware, spam, viruses, and spyware. Today, web filtering

forms the First line of defense against web-based attacks

In addition to client workstations,

web servers, and ISPs, web filters were added to other network devices, such as firewalls, proxy

servers, sandbox technology, and wireless access points

How does a web filter work? A web filter can consult a URL database that lists websites and

domains that are known to host malware, phishing, and other harmful tools.

The URLs found on this naughty list

are also known as a Deny list. There can also be an Allow list, which is a sanctioned list of URLs

Another method that can be used is a filter that looks for a keyword or predefined content.

the problem with this method is the number of false positives; that is, it can

inadvertently block legitimate content, such as art.Machine learning may, in time, overcome

this deficiency

https://training.fortinet.com/pluginfile.php/1625695/mod_scorm/content/1/story_content/external_files/NSE%202%20Web%20Filter%20Script_EN.pdf

Secure Email Gateway

•  Spam—the act of sending Irrelevant and unsolicited messages on the

internet to a large number of recipients.

Phishing to describe the fraudulent practice of

Sending emails purporting to be from a reputable source, in order to induce individuals to

reveal personal information

Spam filters rely on Identifying specific words or patterns in the headers or bodies of messages

ISPs began to implement the Sender Policy Framework SPF, which slowly took shape

during that decade but wasn’t proposed as a standard until 2014.

SPF is an Email authentication method that Detects bogus sender addresses and emails. 

Secure email gateways arose to provide more rigorous defense. In

addition to the spam filter, they added Antivirus scanners, Threat emulation, and Sandboxing to

detect malicious attachments and links in real time

Today, greater Automation and Machine learning are built in to secure email gateways, which

alleviates the demands placed on security operations centers. Data loss prevention DLP is also

available to detect and stop the egress of sensitive data. 

In some cases, a secure email gateway isintegrated with other network security devices, such

as edge and segmentation firewalls

https://training.fortinet.com/pluginfile.php/1625638/mod_scorm/content/1/story_content/external_files/NSE%202%20Secure%20Email%20Gateway%20Script_EN.pdf