Selection and Testing of Electronic Components for LM

Software for/he
switching system
(APT)
Standard products
36 %
Software for the
switching system
New production
4 %
Fig. 4
Distribution of the software volume between
standard and new production
Fig. 5
then added, fig. 3. Thanks to the block
structure of the software it has thus
been possible to create standard allocations,
despite functional differences between
different exchanges, a fact which
has been a considerable help in reducing
an administration's costs.
The far-reaching standardization has
meant that nowadays when LM Ericsson
deliver an exchange in a new market
it is only necessary to design on average
4% of the total amount of software
to be included in the exchange.
The remainder can be collected as verified
standard products from a library,
fig. 4, without any changes being
necessary.
AKE 13 in the international
network
When AKE 13 was designed, one of the
prerequisites was that the system
should be suitable for the handling of
international and intercontinental traffic
with particularly complex demands.
The large traffic handling capacity,
adaptability to different signalling sys­
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tems and traffic routing requirements
and the comprehensive maintenance
functions are examples of characteristics
that are important for the international
traffic and which it has been possible
to realize through the SPC technique.
Of the 36 AKE 13 exchanges which
have hitherto been put into operation or
ordered, no less than 14 are international
exchanges (table 1).
System AKE 13 is able to provide all traffic
facilities that have been agreed internationally,
and the system is suitable
for all levels in the international
hierarchy. Today practically all the international
signalling systems are in
operation in AKE 13 exchanges, namely
R1, R2, CCITT 4, CCITT 5 and CCITT 6.
Facilities for connecting echo suppressors,
individual ones or from a common
group, and for automatically connecting
in and disconnecting attenuators
are built into the system. All current
forms of international accounting are
catered for. Charging can be carried out
by means of repeated metering pulses
or toll ticketing. For example, pulse
charging can be used for the national
traffic and toll ticketing for the international
traffic.