It really depends on where the PIX is sitting! If it's on your internet connection then you will need a router to route traffic to the internet. If it sits between two switches then no, you don't need a router! So, if you require routing, put a router in. If you don't require routing, don't put a router in!
With regard to the ethernet interface, it all depends on what you are connecting to. If your switch supports full duplex then set the PIX eth port up for full duplex. Setting it to auto is usually does the trick.
Chris.
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Chris Andrew, CCNA
chrisac@gmx.co.uk
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