User Manual - Configuration Guide (Volume 3)
Versatile Routing Platform Chapter 1
VPN Overview
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Extranet VPN means that the VPN extends Intranet to partners and clients thro ugh
VPN, so that different enterprises can build their VPNs through public net works.
IV. According to networking model
1) Virtual Leased Line (VLL)
VLL simulates the conventional leased line service, i.e., sim ulating the leased line with
IP network and providing asymmetrical and inexpensive “DDN” service. For the users
at both ends of VLL, the VLL is equivalent to the previous leased line.
2) Virtual Private Dial-up Network (VPDN)
In VPDN, VPN is implemented with dial-up and access services (ISDN PSTN) of public
network, which provides access service for enterprises, mini ISPs and m obile offices.
3) Virtual Private LAN Segment (VPLS) service
In VPLS, LANs can interconnect through virtual private network segment, which is the
extension of LAN across IP public network.
4) Virtual Private Route Network (VPRN) service
There are two types: one is the VPRN, using with such conventi onal VPN protocols as
IPSec and GRE, and the other is VPN in MPLS mode.