[LARTC] Split Access Detail Question

[Carol Anne Ogdin <caogdin@xxxxxxxxxxxxx>]

In LARTC (v1.32), under 4.2.1 Split access, the following note appears:

>Reader Rod Roark notes: 'If $P0_NET is the local network and $IF0 is
>its interface, the following additional entries are desirable:
>
>       ip route add $P0_NET     dev $IF0 table T1
>       ip route add $P2_NET     dev $IF2 table T1  ***
>       ip route add 127.0.0.0/8 dev lo   table T1
>       ip route add $P0_NET     dev $IF0 table T2
>       ip route add $P1_NET     dev $IF1 table T2  ***
>       ip route add 127.0.0.0/8 dev lo   table T2

I've market two particular lines for my question:  Wouldn't these two lines
(marked with ***) explicitly permit traffic arriving on $IF1 ($P1_NET) to
be routed back out on $IF2 ($P2_NET), and vice versa?  Under what
conditions would I want traffic arriving at my router from ISP #1 to be
sent back out to ISP #2, or vice versa?  Have I overlooked something
important here?

--Carol Anne
                                                                                    
 Carol Anne Ogdin            http://www.net-working.com                530/295-3657 
                                                                                    
 Deep Woods Technology, Inc.  http://www.deepwoods.com        CAOgdin@xxxxxxxxxxxxx 
                                                                                    
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