The software for either the Cisco or Nortel products can be loaded, but you may have issues running them both at the same time. I believe Windows 2000 will do the job much better than NT 4.0, but that depends on your level of experience with the products.
Remember, both VPNs are based on a form of IPSec and other IP security measures that may depend on the same source code methods and/or procedures. Your device/host must be able to understand the IP traffic to de-encrypt.
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This was first published in April 2002