File encryption
Encryption is the most common and essentially the simplest way to protect any information. After all, it seems that it could be simpler to take the text, take some algorithm…

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Anonymous proxies
A proxy server is the link between users and the Internet. Proxy server - a server that is constantly on the Web, transmitting all user computer requests to the network,…

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What is a firewall and why is it needed?
We will not go into little things like translating words, occupying them some part of the article. Just point out that a firewall (from the English - fire wall), or…

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protocols that use checksum calculation

PPTP VPN

This protocol allows you to implement a secure point-to-point connection by creating a tunnel in an insecure network.

The work of PPTP is to implement PPP frames in IP packets for transferring them to any IP network, including the Internet. In addition, this technology can be used to create a tunnel between local networks.

A TCP connection is used to service the created PPTP tunnel.

Brief specification
The protocol specification was published in 1999 in RFC2637, but the IETF community has not ratified it.
Less secure than IPSec, PPTP establishes a PPP session using the GRE protocol. The 1723 TCP port is used to control and initiate the GRE connection. Redirecting PPTP to the firewall is difficult because the protocol requires two sessions to be established simultaneously. Continue reading

How the media have changed Mankind, and Manchestovo has changed the media over the past couple of thousand years
Today, mass communication is the most important form of information exchange. Newspapers, radio, television and, of course, Internet access allow not only to receive almost any information, but also serve…

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If you blocked the site at work
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Internet Marketing Cost Effectiveness
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