LANCOM 821 ADSL/ISDN – LANCOM 1621 ADSL/ISDN – LANCOM 1711 VPN
Chapter 5: Linking two networks
The password for the ISDN connection is an alternative to the use of the ISDN caller ID. It is always used to authenticate callers that do not send an ISDN caller ID. The exact same password must be entered on both sides. It is used for calls in both directions.
The Shared Secret is the central password for security within the VPN. The exact same password has to be entered on both sides
Data compression increases the transfer speed of the connection at no additional cost. This is completely unlike the bundling of two ISDN- chan- nels with MLPPP (Multi Link PPP): The transfer rate will be doubled but there will also be additional telephone costs for two connections.
5.1.2Settings for the TCP/IP router
In TCP/IP networks, addressing has a special significance. Please note that two interconnected networks are logically separate from one another. Each must therefore have its own network number (in our example, '10.0.1.x' and '10.0.2.x'). These network numbers may not be identical.
EN
10.0.1.2 |
10.0.1.100 |
(0123) 123456 |
'server.head.company'
'pc1.branch.comany |
10.0.2.10 |
VPN or ISDN |
connection |
10.0.2.100 |
(0789) 654321 |
LAN of head office. | LAN of branch office. |
IP: 10.0.1.0, | IP: 10.0.2.0, |
Netmask: 255.255.255.0 | Netmask: 255.255.255.0 |
Domain: 'head.company' | Domain: 'branch.company' |
Unlike when accessing the Internet, all of the IP addresses in the involved net- works are visible on the remote side when coupling networks, not just those of the router. The computer with the IP address 10.0.2.10 in the branch office LAN sees the server 10.0.1.2 in the headquarters and can access it (assuming it has the appropriate rights), and vice versa.
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