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PPTP has many known security issues and we are not recommending to use it. However, this protocol is integrated into common operating systems and it is easy to set it up. PPTP can be useful in networks where security concerns are is not consideredof concern.
PPTP traffic uses TCP port 1723 and IP protocol GRE (Generic Routing Encapsulation, IP protocol ID 47), as assigned by the Internet Assigned Numbers Authority (IANA). PPTP can be used with most firewalls and routers by enabling traffic destined for TCP port 1723 and protocol 47 traffic to be routed through the firewall or router. PPTP includes PPP authentication and accounting for each PPTP connection. Full authentication and accounting of each connection may be done through a RADIUS client or locally.
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