Paywall
A paywall is a method of restricting access to content via a paid subscription. Beginning in the mid-2010s, newspapers started implementing paywalls on their websites as a way to increase revenue after years of decline in paid print readership and advertising revenue. In academics, research papers are often subject to a paywall and are available via academic libraries that subscribe.
Data center security
A firewall is a sophisticated filtering device that separates LAN segments, giving each segment a different security level and establishing a security perimeter that controls the traffic flow between segments.Firewalls are most commonly deployed at the Internet Edge where they act as boundary to the internal networks.They are expected to have the following characteristics: Performance: the main goal of a firewall is to separate the secured and the unsecured areas of a network. Firewalls are then post in the primary traffic path potentially exposed to large volumes of data. Hence, performance becomes a natural design factor to ensure that the firewall meets the particular requirements.