Specifications

TNPP Networking
184 025-9034AA
Tone-only, numeric, and alphanumeric display paging can be done; voice paging is not
supported. This is a limitation of TNPP in itself, not our system. You may configure the
Series 2000 so that a call to a voice pager will have the voice message transmitted at the
terminal of origin, and cause an alert page sent over the network. Combining this with the
Insurance mode of PagerSaver allows a subscriber with a voice pager to take advantage of
wide area network paging.
Each node is assigned its own address, the node address or node ID that is unique within
the particular network of which the node is a part. This node address is often referred to as
the primary node address and may be used to identify what node is the origin of a packet,
and to direct a packet to a particular node.
With some implementations of TNPP, including Zetron’s, a node may have several
secondary node addresses. A secondary address may be used simply as an alias for a given
node, used to separate classes of pages for some reason. A secondary address may also be
shared by several terminals in what is called page and pass. This allows the assigning of a
single secondary node address to some wide area function. As an example, a group of
terminals might use the secondary address “5555” for networking “wide area P5” pages.
The page and pass mode of operation is quite useful. It makes managing paging areas
simpler, and can considerably reduce the amount of network traffic on larger networks. A
little further on there will be an example of network configuration in which the page and
pass mode is used.
There are two main types of TNPP network configurations. The simplex mode is normally
used for very wide area paging by way of communications satellites (Network USA and
Sports Page are examples). The other network configuration is duplex, which allows a bi-
directional exchange of data between terminals. Duplex is the mode normally used in
paging networks and is the network configuration assumed in this discussion.
There can be many paging terminals on a single TNPP network. Each paging terminal is
identified by a particular “address”. This address, like a street address, uniquely identifies
a particular paging terminal and/or function. A single paging terminal might control
several RF channels, and each one could have its own address.
However, although there may be many paging terminals, or TNPP nodes, connected
together within a network, this does not mean that the terminals are all connected with a
common circuit. Rather the terminals are “daisy chained” together, with a pair of nodes
connected by each link. Pages are passed from terminal to terminal, in a bucket brigade
fashion, until they reach their destination.
Although duplex mode restricts terminals to only two terminals on each circuit, any single
terminal may be directly connected to many other terminals. Zetron allows the connection
of up to eight other nodes to any terminal. With this flexibility, the overall “wiring
diagram” of a TNPP network can be quite complex. The page and pass mode of operation
can reduce the effort in programming a larger network.