Configure the desired access control for this example by building an exclusive filter
on the PPP/0 interface of router 4.3 as shown in Figure 17. Toconfigure the
example given for router 4.3 in Figure 17, enter the following NCP commands and
parameters:
NCP> def mod access-cont circ ppp/0 type exclusive
NCP> def mod access-cont circ ppp/0 filter 0.0 0.0 4.4 63.1023
NCP> def mod access-cont circ ppp/0 state on
Managing Traffic Using Area Routing Filters
Area routing filters allow special configurations of your DNA network. Because this
is an advanced topic, very few DNA IV networks need routing filters. There are two
primary applications for area filtering in DNA IV:
vSecurity, limiting access to some group of areas from other areas.
vAllowing the blending of two DECnet address spaces.
Note: Area Routing Filters are very tricky and subtle to configure. It is very easy
to completely break your area routing. If you do not understand how
DECnet routing works, especially at the area level, do not try to use
routing filters. Documentation on the DECnet routing protocol can be
found in

DECnet Digital Network Architecture Phase-IV Routing Layer

Functional Description

, Order Number AAX435ATK,December 1983,
Digital Equipment Corporation, Maynard, Massachusetts.
Source
Result Source
Mask Destination
Result Destination
Mask
Exclusive Filter Information
0.0 0.0 4.4 63.1023
4.1 4.4
4.3
Rest of Campus
4.5 4.64.2
Eth/0
PPP/0
Figure 17. Example of ExclusiveAccess Control
Using DNA IV
256 MRS V3.2 Protocol Config Ref Vol2