[ale] Networking implementation question

[Pete Hardie]

All,

With the arrival of my oldest's teen years, and the unfortunate
influences of classmates and such, I'm trying to set up a variety of
filtering and monitoring tools so that should something
untoward happen online, I can get advance notice, and so I can block
the more egregious content.  However, I'm relatively unskilled as a
network admin, so I am having trouble finding the exact tutorials for
what I want.

Here's the plan:

I have wireless bridging to the kids' computer, and to my ReplayTV in
the bedroom.  I have
wired connectivity in the office to my machine, the wife's machine,
another ReplayTV, and the
wireless bridge.  I want to put a recycled linux box between the
wireless bridge and my DSL modem/router, so that I can run squid,
squid-proxy, and various monitoring tools on the traffic from the
kids' machine, with the ability to let the bedroom Replay get out to
the Internet unobstructed.

ASCII Art diagram:
currently:
ReplayTV2---wireless bridge 2********
                                                   *
My 'puter----DSL Router                *
wife's 'puter---------|                        *
ReplayTV1----------|                        *
wireless bridge 1--|*********************
                                                   *
kid's machine---wireless bridge 3*****

where - and | are wired links, and * is wireless

desired:
ReplayTV2---wireless bridge 2***************
                                                             *
My 'puter----DSL Router                            *
wife's 'puter---------|                                    *
ReplayTV1----------|                                    *
proxy box------------|                                     *
        |---------------------------wireless bridge 1--|**
                                                               *
kid's machine---wireless bridge 3**************

with the proxy box having 2 NICs

What I can't determine is which of IP Masquerade, IP-forwarding,
ethernet bridging, and routing is necessary for me to achieve this.

Any suggestions appreciated!

TIA,

-- 
Pete Hardie
--------
Better Living Through Bitmaps