3Com Dual 56K User Manual

Also see for 3C888 - OfficeConnect Dual 56K LAN Modem Router: Getting started guide

Contents

3Com Dual 56K User Manual Manual pdf 29 page image

Support for Virtual Private Networks (VPNs) 29Support for VirtualPrivate Networks(VPNs)Through its support of the Point-to-Point Tunnel Protocol (PPTP), the Dual 56KLAN Modem allows users on any workstation attached to the LAN Modem tocommunicate with a remote private network over the Internet using a VirtualPrivate Network (VPN) tunnel, provided the necessary client software is installedon the user’s workstation.Although the LAN Modem allows for the transparent passage of VPN tunnel datafrom a computer on its LAN side to its WAN side, the LAN Modem cannot itselfinitiate or terminate a tunnel. In other words, the LAN Modem does not encrypt orencapsulate data on the outgoing side of the VPN connection, nor does it act as atunnel terminator to unpack tunnel packets on the incoming side.VPN tunnels are a private, secure means by which content-sensitive data that usesany routing protocol can be transported over the public, IP-routable-only Internet.Because a VPN tunnel is established through a local call to an Internet ServiceProvider, a user connecting to a remote Private Network through a VPN tunnel caneliminate long distance charges that might otherwise be incurred from dialingdirectly to the remote private network.Figure 14 shows a VPN tunnel connection to a remote private network using asingle, locally-dialed ISP call.Figure 14 VPN Tunnel Connection to a Remote Private Network via an ISPTo create a VPN tunnel from a workstation attached to the Dual 56K LAN Modem,no special configuration of the LAN Modem is required. The client workstationmust, however, have the appropriate software, and a tunnel server must be set upat the remote private network.Basic instructions for setting up and initiating a VPN tunnel from a clientworkstation are provided in Appendix C, “Creating a Virtual Private Network(VPN) Tunnel.”Public telephonenetworkDual 56K LAN ModemWorkstationwith PPTPclient softwarePPTP TunnelserverVPN tunnelCorporate officeLANMore connected3 ComStatusResetTXDD1 212431/23/4 3 4RXTXLKRXLANRemote Access System 1500WAN COPowerBRI ISDN UANALOGSLOT 1SLOT 2STACKNETCONSOLESUPERSTACK3ComAlert PowerMessageRDAA CD SD OH RDAA CD SD OH 1TX COLL 2 3 4OfficeConnect Dual 56k LAN ModemLAN StatusMODEM 2MODEM 1Internet