Experiences with ADSL Routers

FAQ #100203

For our Webserver Demo installation we have worked with different ADSL Routers, none of which was perfect.


Our Webserver Demo installation is connected to the Internet via an ADSL Link on an ISDN line, which is provided by www.green.ch. This provider offers fixed IP addresses for a good price and can be recommended vividly to all Swiss Customers.

Criterias to choose an ADSL Router

  • you need to know whether an analogue or ISDN version is required (depends on the telephone line)
  • it must support "nailed up connections", which means that if the internet connection is not closed periodically and if for some reason the connection gets lost anyway, the Router re-establishes the connection
  • it should contain a firewall
  • it should support address translation, so you can route telegrams to port 80 to the PC with WebConnect and telegrams to port 5050 to a PCD directly. Other ports should be blocked inwards
  • an integrated switch is quite useful

Zyxel Prestige 650 ME-I

  • does not support nailed up connections, so you need to run a software on the frontend PC which simulates Web traffic (for instance come.to/StayAlive ), to make sure the installations stays available from outside. Without such a tool the Router closes the Internet connection after a while and you cannot access the frontend PC or PCD anymore until you create Web traffic on the PC
  • user friendly configuration tool

Zyxel Prestige 650 H-I

  • nice product with rich features, 4 Port Switch, supports nailed up connections. Didn't work in our installation, Web traffic was only possible from the LAN to the WAN, but not vice versa, independent of the firewall configuration
  • user friendly configuration tool 

Devolo Microlink ADSL Modem Router

  • nice product with rich features, 4 Port Switch, supports nailed up connections. Blocks periodically in our installation, a power down / power up is necessary to re-establish the Internet connection. Since we cut the supply of the unit for a moment at noon, the product works fine...
  • very bad documentation, configuration tool is not user friendly, not suitable for people that configure an ADSL Router for the first time

General Remarks

  • we bought standard low price Routers, which are designed to let a workgroup share an Internet connection. With the Webserver we use the product the other way around, which can cause problems with some products
  • do not expect to get useful support from the suppliers of ADSL Routers in this class. If the product does not work in your installation, it is worth returning it and try another model from the same or from another manufacturer
  • using an output of the PCD to cut the supply of the Router periodically has proved to be a good idea. The cheap routers are usually used in an environment where somebody can interact easily in case of problems (private use at home), for Webserver applications in the field this is not always that easy





S-Web Technology / ADSL

Last update: 28.05.2015 16:31

First release: 17.08.2004 10:19

Views: 3893

The requested software / document is no longer marketed by Saia-Burgess Controls AG and without technical support. It is an older software version which can be operated only on certain now no longer commercially available products.