Again, that's because you appear to not know firewalling and you should read up on the topic. All major UNIXes and derivatives (Solaris,Linux,the BSDs,OS X) implement the firewall as a kernel subsystem for the very reason of performance. You are correct that there are vendors which will sell you firewalls as specialized boxes which either run a derived version of said OSes or implement their own OS (more often than not far inferior, see Cisco OS for example). Except for the extreme high end these just contain PC hardware though, the main difference between them and a standard server designed for fast network performance and running a general-purpose OS is just the fancy box and the price-tag.

The term "Personal Firewalls" is from the Windows world and indeed does refer to the toy firewalls implemented as Windows userland programs AFAIK. I believe though that even newer Windows versions implement their firewall at a kernel level (not sure, haven't touched that OS in years).

I didn't think you were talking about running a firewall as a separate box, because in that scenario it is even more obvious that you should block the DOS at the entry point to your network. Otherwise you'd be letting the DOS traffic add load to your internal network traffic as well as the external connection. Also, a dedicated firewall (regardless whether consisting of so-called specialised hardware or a standard UNIX box) will most certainly be much more effective at blocking unwanted traffic than userland programs running on an application server. That's what it's there and designed for after all.

I imagine that it could still read IP tables from a machine that does run application servers however.

Hmm, don't understand this sentence, what do you mean by "IP tables"? Do you mean the Linux iptables firewall?

Marked OT because these are firewall arcana, not Perl


All dogma is stupid.

In reply to OT: Re^9: How to implement a fourth protocol by tirwhan
in thread How to implement a fourth protocol by Moron

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