I. Model
Following is the model VPN clients to site
As models on the client will then connect to their sites through the Internet environment, after the connection is a node on their sites is 1 or node in the LAN, when it can make the exchange of data back to the PC in your LAN.
II. [...]

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Why do my VPN connections work from some locations and not others?
1. The Internet service provider (ISP) that you are using at the time of the connection may be blocking specific types of TCP/IP traffic that are preventing VPN connectivity. For example, PPTP traffic uses TCP port 1723 to create the connection and IP [...]

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