Netopia 435 Reference Manual page 131

6-18 Netopia ISDN Router Reference Guide
Number Remapping and toggle it to Yes.
It is strongly recommended that you enable network number
remapping if you plan on using AURP. With remapping, Netopia
will substitute network numbers not used by your network for
the numbers of other remote networks. Theses safe numbers
will only be used by local routers on your network; remote
routers will not be aware of the remapping.
When network number remapping is enabled, you must choose
a safe range of network numbers as a destination for the
remapping. A safe range of network numbers is exclusive of
(that is, does not intersect) your local AppleTalk network's
range of network numbers.
To choose a destination range for the remapping, select From
under Remap into Range and enter a starting value. Select To
under Remap into Range and enter an ending value. Make sure
the range you choose is large enough to accommodate all
expected incoming AURP network numbers.
To improve the efficiency of remapping network numbers into a
safe range, select Cluster Remote Networks and toggle it to
Yes. This setting takes any number of remote networks being
remapped and causes them to be remapped into a continuous
range.
To override the AppleTalk maximum limit of 15 hops, select
Enable Hop-Count Reduction and toggle it to Yes. This will
cause hosts on a local AppleTalk network to "see" AppleTalk
destinations across the IP tunnel as being only one hop away.
AppleTalk allows a packet up to 15 hops (going through 15
AppleTalk routers) to reach its destination. Packets that must
reach destinations more than 15 hops away will not succeed.
However, when tunneling through a large internet a packet
could exceed that limit. For example, if two large AppleTalk
internets, each consisting of eight or more routers, it would be
possible that packets from the far end of one internet could
reach the far end of the other internet. In this case, hop count
reduction would make this kind of packet transmission
possible.