Note:
I've used these shapes only with Dia-win32-v0.88 and really don't know if they'll work with other versions or platforms (I assume they would but haven't tested it).
network2.tar.gz
Vague directions:
  1. Save above file to dia directory
  2. unzip & untar (once completed there should be a new sheet file in the "sheets" directory and a new shape directory under "shapes")
  3. Restart dia
Here's a look at the shapes themselves (images in .png format):
generic_router: |
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generic_switch: |
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generic_switchengine: |
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