Note: Descriptions are shown in the official language in which they were submitted.
2024215
BACKGROUND OF THE INVENTION
The present invention is directed to a cross-connect
method for STM-1 signals of a synchronous digital multiplex
hierarchy upon multiple employment of demultiplexing methods
wherein each STM-1 signal is first divided into three or,
respectively, four upper units and these are subsequently
respectively divided into tributary units including individual
outputs for the separation of 1544, 6312, 44736, 2048, 8448,
and/or 34368 kbit/s signals, optionally via different paths,
upon multiple employment of multiplexing methods that reverse
these demultiplexing methods, and upon employment of methods
for the operation of a switching matrix network.
' The above-referenced multiplexing and demultiplexing
methods are known, for example, from CCITT Recommendation
6.709, FIG. 1.1/G.709 and from a.multiplex structure that was
disclosed at the European Transmission Standards Institute
ETSI at the TM3 Meeting (Transmission and Multiplexing) in
Brussels between April 24 and 28 1989.
German Published Application DE 35 li 352 A1 discloses
a method and a switching equipment for distributing
plesiochronic broadband digital signals, whereby these
signals, controlled by a central clock, are converted into
intermediate digital signals containing auxiliary signals upon
filling and, after passing through a switching matrix network,
are in turn re-converted into plesiochronic broadband digital
signals.
In one method (P 39 23 172.0 , a post-published German
patent application) data blocks of different multiplexing
levels are converted into cross-connect data blocks that are
ordered in a fixed super-frame for a transmission bit rate of
38 912 kbit/s (D39 signal).
2
~0~4~~.5
SZJMMARY OF THE INVENTION
An object of the present invention is to provide a method
with which data blocks having differing multiplex structure
can be converted into cross-connect data blocks.
This object is achieved by a method according to the
present invention in which: STM-1 signals are resolved in the
demultiplexing methods into virtual container groups of
approximately the same length; an individual switching matrix
network clock matching pointer and an individual switching
matrix network overhead are respectively attached to these
virtual container groups for the formation of uniform
switching matrix network input signals upon waiver of
auxiliary signals that are no longer required; controlled by
the signal content of the switching matrix network input
signals and/or by a network management, switching matrix
network input signals deriving respectively from an upper unit
are supplied to the switching matrix network; the virtual
containers of the switching matrix network input signals are
rearranged before acceptance into the switching matrix network
output signals; the switching matrix network overheads are
taken from the switching matrix network output signals and are
evaluated; the switching matrix network output signals are
respectively subjected to a multiplexing method for the
formation of STM-1 output signals; and controlled by the
signal content of the switching matrix network output signals
and/or by the network management, respectively one path in the
multiplexing method is thereby selected.
In further developments of the present invention the
following can be incorporated with the above-described method.
A switching matrix network frame alignment signal, switching
matrix network route addresses, and switching matrix network
3
2024225
quality monitoring information can be provided as switching
matrix network overhead. A switching matrix network overhead
can be attached only to the switching matrix network input
signals supplied to the switching matrix network. Virtual
container groups 16 x VC-12, 4 x VC-22, 1 x VC-31, 20 x VC-
11 and/or 5 x VC-21 can be provided. Switching matrix network
clock matching pointers TU-12 PTR (KF), TU-22 PTR (KF), TU-
31 PTR (KF), TU-11 PTR (KF) and/or TU-21 PTR (KF) can be
provided, and switching matrix network input signals and
output signals (D39) having a bit rate of 38912 kbit/s can be
provided. Virtual container groups 28 x VC-11, 7 x VC-21,
1 x VC-32 and/or 21 x VC-12 can be provided: switching matrix
network clock matching pointers TU-11 PTR (KF), TU-21 PTR
(KF), TU-32 PTR (KF) and/or TU-12 PTR (KF) can be provided;
and switching matrix network input signals and output signals
(D52) having a bit rate of 51968 kbit/s can be provided. For
the input side of the switching matrix network, wherein a VC-
4 virtual container is taken from a STM-1 signal from its AU-
4 administration unit upon out-coupling and evaluation of an
AU-4 PTR administration unit pointer, wherein the C-4
container is taken from the VC-4 virtual container upon out-
coupling and evaluation of its VC-4 POH path overhead and
wherein the C-4 container is divided into four alternative
pairs each respectively composed of one TU-3x tributary unit
or of one TUG-3x tributary unit group, each alternative pair
can be supplied to two paths connected at the input side and
alternately through-connected to the switching matrix network
at the output side: in the first path, the VC-3x virtual
container can be taken from a TU-3x tributary unit upon out-
coupling and evaluation of the TUG-3x PTR tributary unit
pointer and a TU-3x PTR (KF) switching matrix network clock
4
202~2~.5
matching pointer and a switching matrix network overhead
(KFOH) can be attached to the VC-3x virtual container; and in
the second path, a fixed filling (FS) and a plurality m of
TUG-ly PTR tributary unit pointers can be taken from a TUG-
3x tributary unit group upon evaluation and a plurality m of
TU-1y PTR (KF) switching matrix network clock matching
pointers and a switching matrix network overhead (KFOH) are
attached to the remaining plurality m of VC-1y virtual
containers for the formation of a switching matrix network
input signal (D39, D52) (x = 1 and y = 2 or x = 2 and y = 1).
The VC-3x virtual container can be supplied to a third path
that branches off from the first path: the C-3x container can
be taken from the VC-3x virtual container on the third path
upon out-coupling of its VC-3x POH path overhead; and instead
of a TUG-3x tributary unit group without fixed FS stuffing,
this C-3x container can be supplied into the remaining part
of the second path upon disconnection of the corresponding,
first part of the second path. For four switching matrix
network output signals, wherein a respective VC-4 POH path
overhead is attached to the C-4 containers for the formation
of a VC-4 virtual container, and wherein a respective AU-4 PTR
pointer is attached to the VC-4 virtual containers for the
formation of AU-4 administration units of STM-1 signals,
groups of four switching matrix network output signals can be
formed; each switching matrix network output signal (D39, D52)
can be supplied to two paths that are connected at the input
side and are alternately through-connectable at the output
side; the switching matrix network overhead (KFOH) and the
TU-3x PTR (KF) switching matrix network clock matching pointer
can be taken in the first path for acquiring a TU-3x tributary
unit and a TU-3x PTR pointer can be attached; the switching
_ 20242~.~
matrix network overhead (KFOH) and a plurality m of TU-1y PTR
(KF) switching matrix network clock matching pointers can be
taken in the second path for acquiring a TUG-3x tributary unit
group and a plurality m of TU-ly PTR pointers and a fixed
filling (FS) can be attached; and either the TU-3x tributary
unit or the TUG-3x tributary unit group of each of the four
alternative pairs can be respectively inserted into a C-4
container (x = 1 and y = 2 or x = 2 and y = 1). The TUG-3x
tributary unit group without fixed filling (FS) can be
supplied to a third path branching off from the second path
after the in-coupling of a plurality m of TU-ly PTR pointers;
a VC-3x POH path over-head can be attached to the C-3x
container in the third path for the formation of a VC-3x
virtual container: and this VC-3x virtual container can be
supplied into the remaining part of the first path for the
acceptance of a TU-3x PTR pointer upon disconnection of the
corresponding, first part of the first path. Identical method
steps can be implemented in the first and second path with
respectively one arrangement in time-division multiplex and
switching-aver steps can be triggered by the signal content
and/or by the network management. The method steps can be
controlled by a micro-processor or the execution thereof can
be in an integrated circuit.
A virtual container group is composed of one or more
virtual containers, sub-system units or sub-system unit
groups.
A converter for transition from the structure of a sub-
system unit group TUG-31 or TUG-32 to the structure of a sub-
system unit TU-31 or TU-32 can be realized with this method.
This method is likewise suited for constructing what is
referred to as a drop insert multiplexer for the synchronous
6
CA 02024215 2000-08-10
20365-3054
7
digital multiplex hierarchy.
In accordance with the present invention, there is
provided a cross-connect method for STM-1 signals of a
synchronous digital multiplex hierarchy upon multiple
employment of demultiplexing methods wherein each STM-1 signal
is first divided into three (AU-32, TU-32, TUG-32) or,
respectively, four (AU-31, TU-31, TUG-31) upper units and
subsequently respectively divided into sub-units (TUG-21, TU-
11, TU-12, TUG-22, TU-12, TU-22) including individual outputs
(VC-32, VC-31) to provide at least one of 1544, 6312, 44,736,
2048, 8448, and 34,368 kbit/s signals, optionally via different
paths, upon multiple employment of multiplexing methods that
reverse these demultiplexing methods, and upon operation of a
switching matrix network, comprising the steps of:
demultiplexing STM-1 signals into virtual container groups of
substantially the same length; respectively attaching an
individual switching matrix network clock matching pointer, as
well as, an individual switching matrix network overhead to
these virtual container groups for the formation of uniform
switching matrix network input signals upon waiver of auxiliary
signals that are no longer required; controlled by at least one
of instructions carried in the switching matrix network input
signals and a network management, supplying switching matrix
network input signals deriving respectively from an upper unit
to the switching matrix network; rearranging the virtual
containers of the switching matrix network input signals before
acceptance into the switching matrix network output signals;
taking and out-coupling the switching matrix network overheads
from the switching matrix network output signals; multiplexing
the switching matrix network output signals to form STM-1
output signals; and controlled by the at least one of
instructions carried in the switching matrix network output
CA 02024215 2000-08-10
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7a
signals and the network management, respectively selecting one
path in the multiplexing.
In accordance with the present invention, there is
provided a cross-connect method for STM-1 signals of a
synchronous digital multiplex hierarchy upon multiple
employment of demultiplexing methods wherein each STM-1 signal
is first divided into three (AU-32, TU-32, TUG-32), or
respectively, four (AU-31, TU-31, TUG-31) upper units and
subsequently respectively divided into sub-units (TUG-21, TU-
11, TU-12, TUG-22, TU-12, TU-22) including individual outputs
(VC-32, VC-31) to provide at least one of 1544, 6312, 44,736,
2048, 8448, and 34,368 kbit/s signals, optionally via different
paths, upon multiple employment of multiplexing methods that
reverse these demultiplexing methods, and upon operation of a
switching matrix network, comprising the steps of:
demultiplexing STM-1 signals into virtual container groups of
substantially the same length; respectively attaching an
individual switching matrix network clock matching pointer, as
well as, an individual switching matrix network overhead to
these virtual container groups for the formation of uniform
switching matrix network input signals upon waiver of auxiliary
signals that are no longer required; controlled by at least one
of instructions carried in the switching matrix network input
signals and a network management, supplying switching matrix
network input signals deriving respectively from an upper unit
to the switching matrix network; rearranging the virtual
containers of the switching matrix network input signals before
acceptance into the switching matrix network output signals;
taking and out-coupling the switching matrix network overheads
from the switching matrix network output signals; multiplexing
the switching matrix network output signals to form STM-1
output signals; controlled by the at least one of instructions
carried in the switching matrix network output signals and by
GVJVJ-JVJ~
CA 02024215 2000-08-10
' 7b
the network management, respectively selecting one path in the
multiplexing; for the input side of the switching matrix
network, a VC-4 virtual container being taken from a STM-1
signal from its AU-4 administration unit upon out-coupling and
evaluation of an AU-4 PTR administration unit pointer, a C-4
container being taken from the VC-4 virtual container upon out-
coupling and evaluation of its VC-4 POH path overhead, and the
C-4 container being divided into four alternative pairs each
alternative pair respectively composed of one TU-3x tributary
unit and one TUG-3x tributary unit group, supplying each
alternative pair to two paths connected at the input side and
alternately through-connectable to the switching matrix network
at the output side, in the first path, taking a VC-3x virtual
container from the TU-3x tributary unit upon out-coupling and
evaluation of a TUG-3x PTR tributary unit pointer and a TU-3x
PTR (KF) switching matrix network clock matching pointer and
attaching a switching matrix network overhead (KFOH) to the VC-
3x virtual container, and in the second path, taking a fixed
filling (FS) and a plurality m of TUG-ly PTR tributary unit
pointers from the TUG-3x tributary unit group upon evaluation
and attaching a plurality m of TU-ly PTR (KF) switching matrix
network clock matching pointers and a switching matrix network
overhead (KFOH) to the remaining plurality m of VC-ly virtual
container for the formation of a switching matrix network input
signal (D39, D52) where x=1 and y=2, or where x=2 and y=1;
where m=28 for y=1, or where m=16 for y=2.
In accordance with the present invention, there is
provided a cross-connect method for STM-1 signals of a
synchronous digital multiplex hierarchy upon multiple
employment of demultiplexing methods wherein each STM-1 signal
is first divided into three (AU-32, TU-32, TUG-32) or,
respectively, four (AU-31, TU-31, TUG-31) upper units and
subsequently respectively divided into sub-units (TUG-21, TU-
CA 02024215 2000-08-10
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7c
11, TU-12, TUG-22, TU-12, TU-22) including individual outputs
(VC-32, VC-31) to provide at least one of 1544, 6312, 44,736,
2048, 8448, and 34,368 kbit/s signals, optionally via different
paths, upon multiple employment of multiplexing methods that
reverse these demultiplexing methods, and upon operation of a
switching matrix network, comprising the steps of:
demultiplexing STM-1 signals into virtual container groups of
substantially the same length; respectively attaching an
individual switching matrix network clock matching pointer, as
well as, an individual switching matrix network overhead to
these virtual container groups for the formation of uniform
switching matrix network input signals upon waiver of auxiliary
signals that are no longer required; controlled by at least one
of instructions carried in the switching matrix network input
signals and a network management, supplying switching matrix
network input signals deriving respectively from an upper unit
to the switching matrix network; rearranging the virtual
containers of the switching matrix network input signals before
acceptance into the switching matrix network output signals;
taking and out-coupling the switching matrix network overheads
from the switching matrix network output signals; multiplexing
the switching matrix network output signals to form STM-1
output signals; controlled by the at least one of instructions
carried in the switching matrix network output signals and the
network management, respectively selecting one path in the
multiplexing; for respectively four switching matrix network
output signals, a respective VC-4 POH path overhead being
attached to C-4 containers for the formation of a VC-4 virtual
container, and a respective AU-4 PTR pointer being attached to
the VC-4 virtual containers for the formation of AU-4
administration units of STM-1 signals, forming groups of four
switching matrix network output signals; supplying each
switching matrix network output signal (D39, D52) to two paths
that are connected at the input side and are alternately
CA 02024215 2000-08-10
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7d
through-connectable at the output side; taking the switching
matrix network overhead (KFOH) and a TU-3x PTR (KF) switching
matrix network clock matching pointer in the first path for
acquiring a TU-3x tributary unit and attaching a TU-3x PTR
pointer; taking the switching matrix network overhead (KFOH)
and a plurality m of TU-ly PTR (KF) switching matrix network
clock matching pointers in the second path for acquiring a TUG-
3x tributary unit group and attaching a plurality m of TU-ly
PTR pointers and a fixed filling (FS); and inserting either the
TU-3x tributary unit of the TUG-3x tributary unit group of each
of the four alternative pairs into a C-4 container where x=1
and y=2, or where x=2 and y=1, or where m=28 for y=1; where
m=16 for y=2.
BRIEF DESCRIPTION OF THE DRAWINGS
The features of the present invention which are
believed to be novel, are set forth with particularity in the
appended claims. The invention, together with further objects
and advantages, may best be understood by reference to the
following description taken in conjunction with the
accompanying drawings, in the several Figures in which like
reverence numerals identify like elements, and in which:
FIG. 1 shows a first multiplexing structure;
FIG. 2 shows a sub-system unit super-frame;
FIG. 3 shows a second multiplexing structure;
FIG. 4 shows a virtual container VC-4 with one sub-
system unit TU-31 and three subsystem unit groups TUG-31;
FIG. 5a shows a first demultiplexer;
FIG. 5b shows a first multiplexes;
FIG. 6a shows a second demultiplexer;
CA 02024215 2000-08-10
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7e
FIG. 6b shows a second multiplexer; and
FIG. 7 shows a second demultiplexer and multiplexer
controlled in common.
DESCRIPTION OF THE PREFERRED EMBODIMENT
FIG. 1 shows the multiplexing structure of CCITT
Recommendation 6.709, FIG. 1.1/G.709. The references; AU
denotes administration unit, C denotes container, H denotes
digital signal, STM denotes synchronous transport module, TU
denotes tributary unit, TUG denotes tributary unit group and VC
denotes virtual container.
The digital signals to be transmitted are inserted
into containers C-n at the input node to the synchronous
network with positive filling. Every container is augmented to
form
202~21~
a virtual container VC-n by attaching a path overhead POH,
these virtual containers being periodically transmitted. The
first byte of a virtual container is indicated by a painter
PTR whose chronological position in the transmission frame is
fixed. The virtual container of a higher hierarchy level
usually serves as such. A virtual container VC-n together
With the pointer allocated to it forms a tributary unit TU-
n. A plurality of these having the same structure can in turn
be combined to form a tributary unit group TUG-n. The afore-
mentioned CCITT Recommendations cite tributary unit groups
TUG-21 for the North American 1.5 Mbit/s hierarchy and TUG-
22 for the 2-Mbit/s hierarchy that, for example, is standard
in Europe.
FIG. 1 shows the various ways via which a multiplexing
or demultiplexing is possible. Thus, fbr example, sixty-four
H12 signals can be inserted into the virtual container VC-4
either directly via the tributary unit group TUG-22 ox via the
route via the virtual container VC-31 and the formation of the
tributary unit TU-31.
As FIG. 2 or the CCITT Recommendation 6.709, FIG.
3.13/G.709 show, the tributary units TU-12 or, respectively,
TU-22 are subdivided in super-frames of 500 ~,s each. Such a
super-frame contains four frames having a period duration of
125 ~s. The first byte V1, V2, V3 and V4 of each and every
frame is defined in the CCITT Recommendation 6.709. The bytes
V1 are always situated in the first line of a super-frame.
The path overhead POH of the virtual container VC-31 or,
respectively, of the virtual container VC-4 defines the super-
frame with a byte H4. The first line is identified by a byte
J1. Thus, given the direct insertion of the tributary unit
group TUG-22 into the virtual container VC-4, the path
8
~o~~~~~
overhead POH of the virtual container VC-4 determines the
position of the bytes Vn, whereas, given an insertion via the
virtual container VC-31, the path overhead VC-31 POH of the
virtual container VC-31 defines the arrangement of the bytes
Vn.
Both methods have their advantages and disadvantages.
The same multiplexing equipment, however, are required at both
ends of a connection when a converter is not inserted into the
connection that, for example, shapes the sixteen tributary
unit groups TUG-22 of the one path into four tributary units
TU-31 of the other path. This is also valid for the
transmission of a maximum of sixteen 8448 kbit/s signals or
for a mixing of 8448 kbit/s signals and 2048-kbit/s signals
(H12 signals). The analogous case is true for the formatting
of the virtual container VC-4 via twenty one tributary unit
groups TUG-21 or three tributary units TU-31 for the 1.5
Mbit/hierarchy in the upper part of FIG. 1.
34368-kbit/s signals (H21 signals) can be inserted only
by way of the virtual container VC-31 and the tributary unit
TU-31. A mixing of n x 4 tributary unit groups TUG-22 with
4 - n tributary units TU-31 with n = 1, 2 , 3 or 4 is not
provided according to CCITT Recommendation 6.709.
The arrangement of FIG. 3 of ETSI differs from that of
FIG. 1 by the omission of the path from the tributary unit
group TUG-22 via the virtual container VC-31 and the tributary
unit TU-31 to the virtual container VC-4. On the other hand,
it is possible to construct virtual containers VC-4 with a
mixture of n x 4 tributary unit groups TUG-22 and 4 - n
tributary units TU-31. Four tributary unit groups TUG-22 form
one tributary unit group TUG-31. By contrast to a tributary
unit TU-31, this does not have its own pointer and also does
9
202421
not have a common path overhead. However, the pointers of the
tributary units TU-12 or TU-22 belonging to a tributary unit
group TUG-31 are regularly arranged. Their position is
defined by the path overhead VC-4 POH of the virtual container
VC-4. In such a mixture, the first four columns of a
container C-4 contain the TU-31 pointers or a fixed pattern
(filling).
FIG. 4 shows an example wherein two tributary unit groups
TUG-31, one tributary unit TU-31 and a third tributary unit
group TUG-31 are inserted in alternation in a virtual
container VC-4 by columns. On the basis of an evaluation of
the first four columns with fixed fill bytes FS and a pointer
TU-31 PTR, information is obtained as to whether a tributary
unit group TUG-31 or a tributary unit TU-31 is involved. The
virtual container VC-31 that is shown at the bottom right is
inserted by rows in alternation into the third of four columns
after the path overhead VC-4 POH, whereby the position of the
byte J1 is described by the pointer TU-31 PTR. The tributary
unit groups TUG-31 begin in the first, second and fourth
columns with a respective byte V1, there being forty eight of
these in this example.
In digital cross-connectors, as in drop insert
multiplexers, all signals that are to be combined to form a
new output signal must be synchronized to the clock and to the
frame of the output signal. All output signals STM-1 of a
network node have the same clock and the same frame in the
synchronous digital multiplex hierarchy. All signals that are
passed through closed, are divided into tributary units and
are again combined after a switching matrix network must
therefore be synchronized to one another before their
combination.
to
~Q~~~~~
FIG. 5a shows a demultiplexer that precedes the switching
matrix network at the input side. The arrangement contains
an AU-4 PTR out-coupling means and evaluator 2, a VC-4 POH
out-coupling means and evaluator 4, a container demultiplexer
with synchronization means 6, a parallel brancher 7, a first
path having a TU-3x PTR-out-coupling means and evaluator 8,
with a TU-3x PTR switching matrix network clock matching
pointer in-coupling means 10, and with a switching matrix
network auxiliary information insertion means 12, contains a
second path having a fixed fill byte out-coupling means 14,
having a multiple TU-1y PTR out-coupling means and evaluator
' 16, having a multiple TU-1y switching matrix network clock
matching pointer in-coupling and synchronizing means 18, and
having a switching matrix network auxiliary information
insertion means 20, as well as, a signal switch-over means 22.
The units 7-22 are present four times for the 2-Mbit/s
hierarchy and axe present three times for the 1.5-Mbit/s
hierarchy, being indicated for the former instance by the four
outputs of the container demultiplexer with the synchronizing
means 6. What is valid for the European hierarchy is x = 1
and y = 2: what is valid for the U.S. hierarchy is x = 2 and
y = 1. The buffer memories required for every clock matching
are not shown here and in the following figures for the sake
of clarity.
' The AU-4 administration unit of a synchronous transport
module STM-1 is supplied to the input 1. The AU-4 PTR pointer
is output and interpreted via an output 3 from the AU-4 PTR
out-coupling means and evaluator 2. The remaining VC-4
virtual container proceeds to the VC-4 POH out-coupling means
and evaluator 4 that evaluates the VC-4 POH path overhead and
outputs it at its output 5. The information about the
11
zo~~~~~
container start and the super-frame status are communicated
to the following circuits 6, 18, 14, 16, 18 and 20. The C-
4 container proceeds to the container demultiplexer with
synchronizing means 6. Therein, it is divided into four TU-
3x tributary units for the 2-Mbit/s hierarchy and into three
TU-3x tributary units, four TUG-3x tributary unit groups or
a mixture of the two for the 1.5-Mbit/s hierarchy. Either a
respective TU-3x tributary unit or a TUG-3x tributary unit
group are supplied to the four parallel branchers 7.
A check to see whether a TU-3x PTR pointer or whether
fixed fill bytes FS are present is carried out in the TU-3x
PTR out-coupling means and evaluator 8 in the first path and
in the fixed fill byte out-coupling means 14 in the second
path. When a TU-3x PTR pointer is present, this is evaluated
and output via an output 9. The information about the
container start and the super-frame status are communicated
to the following circuits 10 and 12. When fixed fill bytes
FS are present, these are output via an output 15.
A VC-3x virtual container with its source clock may be
available at the output of the TU-3x PTR out-coupling means
and evaluator 8. In the TU-3x switching matrix network clock
matching pointer in-coupling means 10, this VC-3x virtual
container is synchronized to the local switching matrix
network clock derived from the network node clock upon
insertion of a TU-3x PTR (KF) pointer for clock matching and,
in the switching matrix network auxiliary information
insertion means 12, is inserted into a switching matrix
network super-frame together with the switching matrix network
auxiliary information KFOH at the input 13. When the output
23 is connected via the signal switch-over means 22 to the
output of the switching matrix network auxiliary information
12
insertion means 12, a D39 digital signal is available at the
output for x = 1 and a D52 digital signal is available at the
output for x - 2. This can be supplied either to a
demultiplexer (not shown) for resolution of the VC-3x virtual
container or to a multiplexer according to FIG. 5b for
constructing a new AU-4 administration unit.
If, however, fixed fill bytes were to be recognized in
the fixed fill byte out-coupling means 14, a TUG-3x tributary
unit group would appear at its main output, and this would be
composed either of sixteen TU-12 tributary units or of twenty
eight TU-li tributary units (m TU-ly tributary units) . In the
multiple TU-1y PTR out-coupling means and evaluator 16, m TU-
1y PTR pointers would be evaluated and eliminated via an
output 17. The m VC-ly virtual containers would proceed from
the multiple TU-1y PTR out-caupling means and evaluator 16 to
the multiple TU-1y switching matrix network clock matching
pointer in-coupling and synchronizing means 18. Upon
insertion of m TU-1y PTR (KF) pointers, it would be
synchronized there to the local switching matrix network clock
and, via an input 21, would be embedded into the switching
matrix network super-frame in the switching matrix network
auxiliary information insertion means 20 upon supply of the
switching matrix network auxiliary information KFOH. If the
signal switch-over means 22 were now to connect the output 23
to the main output of the switching matrix network auxiliary
information insertion means 20, either a D39 digital signal
or a D52 digital signal would likewise proceed to the output
23.
The switching matrix network overhead insertion means 20
expediently also contains a "router" function (time switching
matrix network) with which the chronological sequence of the
13
~024~15
m VC-ly virtual containers can be varied.
The D39 or D52 digital signal now available at the output
23 can be supplied via a time slot-controlled switching matrix
network either to a demultiplexer (not shown) for resolution
of the individual VC-1y virtual containers into plesiochronic
signals Hly via C-1y containers or can be supplied to a
multiplexer conforming to FIG. 5a for constructing new AU-4
administration units.
FIG. 5b shows a multiplexer for the trarfsmission side of
the switching matrix network. The arrangement contains a
parallel brancher 25, a first path having a switching matrix
network overhead out-coupling means 26, having a TU-3x
switching matrix network clock matching pointer out-coupling
means and evaluator 28 and having a TU-3x PTR in-coupling
means 30. The arrangement further contains a signal switch-
over means 32, a container multiplexer 33, a VC-4 POH in-
coupling means 34, an AU-4 PTR in-coupling means 36. The
arrangement also contains a second path having a switching
matrix network overhead out-coupling means 39, having a
multiple TU-ly switching matrix network clock matching pointer
out-coupling means and evaluator 41, having a multiple TU-
1y PTR in-coupling means 43 and having a fixed fill byte in-
coupling means 45.
The multiplexing method is executed in the inverse
sequence of the demultiplexer according to FIG. 5a. First,
the switching matrix network overhead KFOH is out coupled,
evaluated and output via the output 2? in the switching matrix -
network overhead out-coupling means 26. The TU-3x PTR (KF)
pointer is evaluated and output via the output 29 in the TU-
3x switching matrix network clock matching pointer out-
coupling means and evaluator 28. A TU-3x PTR pointer is
14
202421
attached to the remaining VC-3x virtual container in the TU-
3x PTR in-coupling means 30. However, no clock matching by
filling is thereby required since all D39 or, respectively,
D52 digital signals have already been synchronized to the
network node clock before the switching matrix network.
In the case of the D39 or D52 digital signal, the
switching matrix network overhead information KFOH is
evaluated in the switching matrix network overhead out-
coupling means 39 and is output via the output 40. The
remaining m TU-1y tributary units proceed to the multiple TU-
ly switching matrix network clock matching pointer out-
coupling means and evaluator 41 where the m TU-1y PTR (KF)
pointers are evaluated and output via the output 42. Here,
too, no clock matching by filling is required since all D39
or, respectively, D52 digital signals were already
synchronized to the network node clock before the switching
matrix network. The m TU-ly PTR pointers are supplied to the
remaining m VC-1y virtual containers in the multiple TU-ly PTR
in-coupling means 43 via an input 44. Fixed filled bytes FS
are attached into the output TUG-3x tributary unit group in
the fixed fill byte in-coupling means 45.
The position of the signal switch-over means 32 is based
on the signal content of the D39 or, respectively, D52 signal
or is defined by a network management. Occurring in the
container multiplexer 33 is a byte-by-byte nesting of four TU-
3x tributary units for the 2-Mbit/s hierarchy and of three TU-
3x tributary units and/or TUG-3x tributary unit groups for the
1.5-Mbit/s hierarchy. A VC-4 POH path overhead is attached
to the C-4 container in the VC-4 POH in-coupling means 34 via
an input 35. An AU-4 PTR pointer is attached to the VC-4
virtual container formed in this way in the AU-4 PTR in-
~~~4~~~
coupling means 36, so that an AU-4 administration unit of a
synchronous transport module STM-1 can be output at the output
38.
The demultiplexer shown in FIG. 5a and the multiplexes
shown in FIG. 5b is suitable for "drop and insert" functions,
for "routing" functions and cross-connects for signals at the
nodes of TUG-3x tributary unit groups of the ETSI proposal
according to FIG. 3.
With the additional functions shown in FIGS. 6a and 6b,
TUG-2y tributary unit groups of FIG. 1 can also be conducted
into the VC-4 virtual container via VC-3x virtual containers
and TU-3x tributary units and can be handled in a
corresponding way.
By contrast the to the demultiplexer of FIG. 5a, the
demultiplexer of FIG. 6a additionally contains a third path
having a parallel branching 47, having a VC-3x POH out-
coupling means 48 and having a signal switch-over means 50.
By contrast to the multiplexes of FIG. 5b, the multiplexes of
FIG. 6b additionally contains a third path having a switch-
over means 51, having a VC-3x POH in-coupling means 52 and
having a parallel branching 54. When a VC-3x virtual
container is to be through-connected in closed form, then the
path leads via the units 47, 10, 1.2 and 22 or, respectively,
25, 26, 28 and 51. When, however, a VC-3x virtual container
is to be divided into its TU-1y tributary units, then the
paths via the units 47, 48, 50, 16, 18, 20 and 22 or,
respectively, 25, 39, 41, 43, 54, 52 and 51 are activated.
The VC-3x POH path overhead is taken from a VC-3x virtual
container and evaluated in the VC-3x POH out-coupling means
48 via an output 49. This indicates the start byte and super-
frame affiliation for the C-3x container. The content of the
16
C-3x container has the same structure as a TUG-3x tributary
unit group and can therefore be handled farther via the units
16, 18 and 20 as in FIG. 5a.
Correspondingly, a VC-3x POH path overhead is attached
to the VC-3x POH in-coupling means 52 in FIG. 6b via an input
53.
The functions in the respectively first and second paths
shown in FIGS. 5a, 5b, 6a and 6b largely coincide. In FIGS.
5a and 5b, thus, the pointer column of an incoming TU-3x
tributary unit is investigated and gated out in the units 8
and 14. The units 10 and 18 serve the purpose of inserting
the TU-3x PTR (KF) pointer synchronized to the switching
matrix network clack and super-frame and the units 12 and 20
serve the purpose of inserting the switching matrix network
overhead KFOH. The analogous case applies to the multiplexes
side in FIGS. 5b and 6b.
FIG. 7 shows an arrangement in which these parallel
functions are respectively executed by a single function unit.
These are given reference characters wherein the two, original
reference characters are joined by a slash. The VC-3x POH
out-coupling means 48' and the VC-3x POH in-coupling means 52'
must also assume through-connection functions for the
respectively first and second path.
An AU-4 administration unit incoming at the input 1 is
edited in the equipment 2, 4 and 6, is synchronized to the
network node clock and divided into its TU-3x tributary units
or TUG-3x tributary unit groups. A determination is made in
the unit 8/14 to see whether the first point column contains
a TU-3x PTR pointer or fixed fill bytes FS. In the former
instance, only the first three bytes of the column are
evaluated and taken from the signal. In the second instance,
17
by contrast, the entire column having nine bytes is taken.
If the TU-3x tributary unit or the TUG-3x tributary unit group
is to be divided farther, for example into their m TU-1y
tributary units, then the VC-3x POH path overhead is first
resolved in the unit 48' for a TU-3x tributary unit. This step
is eliminated given a TUG-3x tributary unit group.
Subsequently, the m TU-1y PTR pointers must be evaluated in
the unit 16 with the assistance of the byte H4 from the VC-
4 POH path overhead or from the VC-3x POH path overhead. The
synchronization to the switching matrix network clock and
super-frame and an insertion of the TU-3x PTR (KF) pointer or
TU-ly PTR (KF) pointer of the switching matrix network ensues
in the unit 10/18. The D39 or, respectively, D52 signal is
formed by attaching the switching matrix network overhead KFOH
in the unit 12/20.
The formatting of the multiplex signal in the opposite
direction ensues correspondingly between the input 24 and the
output 38. ~ All function units are controlled via a bus system ."
57 by a microprocessor 55 that is connected to a network
management system via a terminal 56.
The invention is not limited to the particular details
of the apparatus depicted and other modifications and
applications are contemplated. Certain other changes may be
made in the above described apparatus without departing from
the true spirit and scope of the invention herein involved.
It is intended, therefore, that the subject matter in the
above depiction shall be interpreted as illustrative and not
in a limiting sense.
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