Why so many packet filters?

[Paul Goyette <paul%vps1.whooppee.com@localhost>]

Taking a quick look, it seems that we have at least four (maybe five)
different packet filters available.

        pf
        ipf
        bpf (and bpfjit)
        npf

Is there a concise description of each, and when to use one vs the
other?


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| Paul Goyette     | PGP Key fingerprint:     | E-mail addresses:      |
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