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LANCOM 3550 Wireless
Chapter 1: Introduction
Internet connection over DSL
Internet
EN
| VPN connection to headquarters |
Brach office with VPN over DSL | Backup connection over |
and backup over UMTS/HSPDA | UMTS/HSPDA |
As an alternative to the ISDN or analog backup method, a UMTS/HSPDA con- nection can assure the availability of the data connection. If the connection to the Internet is established by a router with LANCOM UMTS/VPN Option, the UMTS/HSPDA connection can directly replace the DSL connection in the case of a breakdown. The advantages of the UMTS/HSPDA backup solution com- pared to the ISDN/analog option:
Faster than ISDN/analog: the data rate with UMTS/HSPDA is considerably faster.
Safer than ISDN or analog: if a physical damage of the DSL line is the rea- son for the breakdown, the ISDN/analog line usually breaks down as well because both use the same physical line.
Cheaper than ISDN: the monthly charges for an UMTS/HSPDA account depend upon the tariff well under the charges for an ISDN account. Com- pared to the short time of breakdown of a DSL connection, the higher connection tariffs for the UMTS/HSPDA are not relevant.
Adding the UMTS/HSPDA backup to existing installations is often simply an issue of adding devices with LANCOM UMTS/VPN Option to existing LANCOM devices. In complicated scenarios an existing ISDN backup in a VPN router can be extended by the UMTS/HSPDA backup in a second device. In this case, the routers will exchange the information about accessible routes using the “Routing Information Protocol“ (RIP).
A sophisticated backup system for protection against router hardware failure can be implemented by using VRRP. Two or more routers are installed in a net- work, one of which can replace the other in case of device failure. In addition to normal VRRP, LANCOM devices can link the backup event triggering func- tion to the availability of a data connection. With this additional feature,
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