Advice Plz. Looking for a full featured router dist.
 

I'm looking for some advice here regarding the best router distro to use.

I've been looking around for a few days and found a couple things but I'm not sure they will do all I'm looking for.

Here's what I need it to do (and most do):
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- Firewall (most ports will be blocked)
- NAT
- DHCP

This is what I'd also like it to do:
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- allow variable lease durations(to be retrieved from a DB)
- ability to keep track or connection time(ping clients to ensure they are still connected if not send total connection time back to the DB)
- Bandwidth usage(not really important but would be nice)


I'm sure I'll most likely have to write the DB interaction parts my self but it would be nice if there was something out there that already kept track of connection times.

Thanks for any suggestions