Web filtering is an important method to tackle the preceding issues. It helps regulate online behaviors and reduce security risks by limiting web access, as shown in the following figure. Youcanprevent access to websites by category, such as phishing, social networking, and video websites; prohi...
How Does URL Filtering Work? The basic working process of URL filtering is to compare the URL carried in a URL request with entries in a URL database or URL list. If a match is found, the device performs a corresponding action (permit or deny). If a user manually enters a URL or cl...
Filtering URL usage in this way can help employees become more productive. However, it can also lead to organizations being exposed to security threats, data loss, or legal issues. First, Let Us Understand What Is A URL A URL is the text that is visible in the address bar of all popular...
How Does URL Filtering Work? URL filtering technology compares all web traffic against a URL filtering database, permitting or denying access based on information contained therein. Each website defined in the database is assigned to a URL category, or group, that firms can utilize in one of ...
A DNS filter, also known as a DNS blocker orDNS-based web filter,is a type of content filtering technologyused to prevent access to specific websites or types of content. It works by intercepting requests made by a user’s web browser to resolve domain names into IP addresses and then fi...
Linear filtering of an image is accomplished through an operation calledconvolution. Convolution is a neighborhood operation in which each output pixel is the weighted sum of neighboring input pixels. The matrix of weights is called theconvolution kernel, also known as thefilter. A convolution kernel...
DNS filtering is as simple as it is effective: Domain queries for websites are channeled through a DNS resolver, which finds their IP addresses using DNS name resolution. If the DNS resolver uses a blocklist, the query ischecked against the list. If the IP address in question is on the ...
Ingress filtering is also a feature on switches, which means it can filter traffic on virtual LANs (VLANs) to prevent malicious activity within a private network, such asVLAN hopping. In VLANs, ingress filtering will discard frames whose port is not a member of the VLAN it is trying to ...
However, spam filtering can also flag legitimate emails from companies users actually want to get messages from. In this case, users often have the option to determine the kinds of emails they want and adjust their settings to allow them to pass through the filter. What Is Spam? What Is ...
DNS filtering can blocklist web properties either by domain name or by IP address: By domain:The DNS resolver does not resolve, or look up, the IP addresses for certain domains at all. By IP address:The DNS resolver attempts to resolve all domains, but if the IP address is on the bloc...