AT&T DEFINITY 7200 series - Manual (Page 112)

5-8 ELECTRONIC TANDEM NETWORK (ETN) THROUGH THE ETN AND PNA PACKAGES
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In some cases, the software and/or administration used to implement the above types of networks reside on
the same switch as do the ETN (Standard Network) package or the Private Network Access package. This
is true of extension number portability, release link trunk networks, and distributed communications system
software and/or administration. In other cases, like Software-Defined Network and main-satellite/tributary
networks, the ETN tandem is totally independent of the other network and accesses it through tie trunks.
Extension Number Portability Clusters
Extension number portability (ENP) clusters are groups of System 85 (R2V3 or R2V4) and Generic 2
communications systems, on which ETN software is specially administered for node number routing
among them (see figure 5-4). With ENP, users can easily move from node to node within the cluster and
still retain the same extension number. It is common for ENP clusters to use 5-digit dialing, with the first
digit indicating the node and the final 4 digits representing the true extension number; or to assign all ENP
nodes the same set of RNXs. These dialing schemes are not mandatory, however. In an ENP cluster, it is
only necessary that each extension be identified on every switch.
GATEWAY SWITCH
TO ETN,
DEFINITY G2
HOME RNX = 320
REMOTE RNXS = 220, 221,
230, 231, 420
GATEWAY SWITCH
TO ETN,
SYSTEM 85
HOME RNX = 420
REMOTE RNXS = 220, 221,
230, 231, 320
SYSTEM 85
R2V3, R2V4,
OR DEFINITY G2
(NODE 2)
REMOTE RNXS = 320, 420
HOME RNXS = 220, 221, 230, 231
HOME RNXS = 220, 221, 230, 231
REMOTE RNXS = 320, 420
SYSTEM 85
R2V3, R2V4,
OR DEFINITY G2
(NODE 1)
HOME RNXS = 220, 221, 230, 231
REMOTE RNXS = 320, 420
SYSTEM 85
R2V3, R2V4,
OR DEFINITY G2
(NODE 3)
Figure 5-4. Extension Number Portability Cluster Using Common RNXs