EP0949837A2
Expired / Lapsed
EP
⏱️ 0.0 years remaining
ATM Switch
Assignee: NTT Inc
•
Filing: 1999-03-02
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Granted: —
•
Expires: 2019-03-02
Abstract
Abstract An ATM switch includes a plurality of stages in which each stage has basic switches and the stages are interconnected. The ATM switch includes M×N basic switches per each stage and a part for interconnecting between the stages. The M×N basic switches are divided into N groups. The part connects an output port of each basic switch at a front stage to M input ports of the basic switches at a back stage. At the output port, a wavelength-multiplexing part is used, and, at the input port, a wavelength-demultiplexing part is used. Further, a wavelength-switching part for switching optical signals of M wavelength-multiplexed optical signals arriving from the M wavelength-multiplexing part and outputting the switched wavelength-multiplexed optical signals to the M wavelength-demultiplexing part is used.
Inventors
- 👤 Naoaki Nippon Telegraph & Yamanaka
- 👤 Kohei Nippon Telegraph & Nakai
Bibliographic Details
Application Number
—
Jurisdiction
EP
Data Source
google_patents
Last Synchronized
2026-10-25 16:54
CPC Classifications
H; H04; H04L; H04L12/00; H04L12/54; H04L12/56; H04L12/5601; H04B; H04B10/00; H04B10/80; H04B10/801; H04L49/00; H04L49/15; H04L49/1553; H04L49/30; H04L49/3081; H04L49/45; H04L49/455; H04Q; H04Q11/00; H04Q11/0001; H04Q11/0005; H04L2012/5603; H04L2012/5604; H04L2012/5605; H04L2012/5672; H04L2012/5678; H04L2012/5681; H04Q2011/0007; H04Q2011/0016; H04Q2011/0052; H04Q2011/006
Claims Analysis
Total Claims: 24
Claim 1
Independent Claim
119 words
An ATM switch including S stages (S is
an integer and 2<=S), wherein said each stage
includes a plurality of basic switches, said ATM
switch characterized by: M×N (each of M and N is an integer) basic
switches per said each stage; and interconnecting means for interconnecting
between said stages, wherein said M×N basic switches have N
groups, and said interconnecting means connects a
jth (j is an integer and 1<=j<=N) output port of
said each basic switch belonging to an ith (i is an
integer and 1<=i<=N) group at an (s-1)th (s is an
integer and 2<=s<=S) stage to at least one ith input
port of said basic switches belonging to a jth group
at an sth stage.
Claim 2
Dependent Claim
38 words
The ATM switch as claimed in claim 1,
characterized in that said interconnecting means
includes means, which is provided at said each input
port, for passing cells that are destined for a
desired destination selectively among other cells.
Claim 3
Dependent Claim
38 words
The ATM switch as claimed in claim 1,
characterized in that said interconnecting means
includes means, which is provided at said each
output port, for passing cells that are destined for
a desired destination selectively among other cells.
Claim 4
Dependent Claim
96 words
The ATM switch as claimed in claim 1,
characterized in that said interconnecting means
comprises: means for converting an electronic-signal
cell which is output from said output port into a
first wavelength-multiplexed optical signal which
includes a plurality of optical signals which have
different wavelengths and for outputting the first
wavelength-multiplexed optical signal; means for generating a second wavelength-multiplexed
optical signal by switching optical
signals and outputting the second wavelength-multiplexed
optical signal; and means for converting said second
wavelength-multiplexed optical signal into
electronic-signal cells and inputting at least one
said electronic-signal cells to the input port.
Claim 5
Dependent Claim
179 words
The ATM switch as claimed in claim 1,
characterized in that said interconnecting means
comprises: means for converting a first electronic-signal
cell which is output from said output port
into N optical-signal cells which have different
wavelengths; wavelength-multiplexing means for
generating a wavelength-multiplexed optical signal
by wavelength-multiplexing said N optical-signal
cells; wavelength-demultiplexing means for
wavelength-demultiplexing a wavelength-multiplexed
optical signal into N optical-signal cells which
have different wavelengths; means for converting said N optical-signal
cells into N second electronic-signal cells; input means for inputting at least one of
said second electronic-signal cells to said input
port; and wavelength-switching means for switching
optical signals of M said wavelength-multiplexed
optical signals arriving from said wavelength-multiplexing
means and for outputting the switched
wavelength-multiplexed optical signals to said
wavelength-demultiplexing means, wherein said wavelength-switching means is
provided between said wavelength-multiplexing means
which is connected to jth output ports of said basic
switches belonging to said ith group at said (s-1)th
stage and said wavelength-demultiplexing means which
is connected to ith input ports of said basic
switches belonging to said jth group at said sth
stage.
Claim 6
Dependent Claim
33 words
The ATM switch as claimed in claim 5,
characterized in that said input means comprises
means for passing only electronic-signal cells that
are destined for a desired destination selectively
among said electronic-signal cells.
Claim 7
Dependent Claim
44 words
The ATM switch as claimed in claim 5,
characterized in that said ATM switch further
comprises means for converting said each electronic-signal
cell output from said output port into an
optical-signal cell which has a wavelength
corresponding to the destination of the electronic-signal
cell.
Claim 8
Dependent Claim
75 words
The ATM switch as claimed in claim 5,
characterized in that said wavelength-switching
means includes a barrel shifter which outputs an
optical signal of a pth (p=1,2,...,N) wavelength in
the mth (m=1,2,...,M) wavelength-multiplexed optical
signal into an (m+p)th output of the barrel shifter,
wherein if m+p is k (k is an integer) more than the
number of said wavelength-demultiplexing means, the
barrel shifter outputs the optical signal into an
((m+p)-k)th output of the barrel shifter.
Claim 9
Dependent Claim
30 words
The ATM switch as claimed in claim 1,
characterized in that the ATM switch further
comprises speed-conversion means for converting the
speed of electronic-signal cells output from said
output port.
Claim 10
Dependent Claim
42 words
The ATM switch as claimed in claim 9,
characterized in that said speed-conversion means
comprises: at least a cell buffer; and means for controlling the ratio between
the writing-clock speed of the cell buffer and the
reading-clock speed of the cell buffer.
Claim 11
Dependent Claim
56 words
The ATM switch as claimed in claim 9,
characterized in that said speed-conversion means
comprises: at least a cell buffer; and means for controlling the ratio between
the number of bit expansion data at the input side
of the cell buffer and the number of bit expansion
data at the output side of the cell buffer.
Claim 12
Dependent Claim
46 words
The ATM switch as claimed in claim 1,
characterized in that the ATM switch further
comprises: means for monitoring the arriving rate of
said electronic-signal cells output from said output
port; and means for converting the speed of the
electronic-signal cells according to the arriving
rate.
Claim 13
Dependent Claim
75 words
The ATM switch as claimed in claim 1,
characterized in that the ATM switch further
comprises: at least a cell buffer which temporarily
stores said electronic-signal cells output from said
output port; means for monitoring the rate of said
electronic-signal cells arriving at said cell
buffer; and means for establishing a plurality of ATM
connections between said basic switches so as to
equalize the cell-transmission rates of the ATM
connections by using the arriving rate.
Claim 14
Dependent Claim
29 words
The ATM switch as claimed in claim 9,
characterized in that the ATM switch further
comprises means for establishing routes of ATM
connections having a plurality of service classes.
Claim 15
Dependent Claim
67 words
The ATM switch as claimed in claim 1,
characterized in that the ATM switch further
comprises: monitoring means for monitoring the
arriving rate of said electronic-signal cells; detecting means for detecting traffic
congestion of a route between said basic switches by
using the arriving rate; and means for prohibiting the ATM switch from
establishing an ATM connection on the route in which
said traffic congestion is detected.
Claim 16
Dependent Claim
27 words
The ATM switch as claimed in claim 15,
characterized in that said monitoring means and
detecting means are provided at the input port of
said basic switch.
Claim 17
Dependent Claim
29 words
The ATM switch as claimed in claim 15,
characterized in that said detecting means includes
means for transmitting the result of the detection
to at least one basic switch.
Claim 18
Dependent Claim
141 words
The ATM switch as claimed in claim 1,
characterized in that the ATM switch further
comprises: monitoring means for monitoring the
residual bandwidth of a port of said basic switch; means for sending an RM (Resource
Management) cell to a plurality of routes; sending-back means for receiving and
sending back the RM cell; and prohibiting means for prohibiting the ATM
switch from establishing an ATM connection on a
specific route according to the RM cell which is
sent back, wherein, if said monitoring means detects
that the residual bandwidth is less than a
predetermined value, said sending-back means
includes information of traffic congestion into the
RM cell and sends back the RM cell, and said
prohibiting means prohibits the ATM switch from
establishing an ATM connection on a route indicated
by the content of the RM cell which is sent back.
Claim 19
Dependent Claim
36 words
The ATM switch as claimed in claim 18,
characterized in that said prohibiting means
includes means for adding a header for avoiding a
congested route to a cell according to the content
of the RM cell.
Claim 20
Independent Claim
116 words
A device in an ATM switch in which a
plurality of stages are interconnected, wherein the
stage has a plurality of basic switches, characterized in that said device converts an
electronic-signal cell output from an output port of
the basic switch into a wavelength-multiplexed
optical signal, said device comprising: means for converting said electronic-signal
cell into a plurality of electronic-signal
cells; converting means for converting said
electronic-signal cells into optical-signal cells of
different wavelengths; and means for wavelength-multiplexing said
optical-signal cells, wherein, at the destination of said each
optical-signal cell, said each optical-signal cell
is converted into an electronic-signal cell and the
electronic-signal cell is input into an input port
by being selected among electronic-signal cells.
Claim 21
Independent Claim
116 words
A device in an ATM switch in which a
plurality of stages are interconnected, wherein the
stage has a plurality of basic switches, characterized in that said device converts a
wavelength-multiplexed optical signal in which a
plurality of electronic-signal cells of different
destinations are wavelength-multiplexed into
electronic-signal cells and inputs one of the
electronic-signal cells into an input port of said
basic switch, said device comprising: means for generating a plurality of
optical-signal cells by wavelength-demultiplexing
said wavelength-multiplexed optical signal; means for converting said optical-signal
cells into said electronic-signal cells; and means for selecting an electronic-signal
cell destined for the input port among said
electronic-signal cells and inputting the selected
electronic-signal cell to the input port.
Claim 22
Independent Claim
122 words
A device in an ATM switch in which a
plurality of stages are interconnected, wherein the
stage has a plurality of basic switches, characterized in that said device converts an
electronic-signal cell output from an output port of
the basic switch into a wavelength-multiplexed
optical signal, said device comprising: means for selecting a wavelength
corresponding to the destination of said electronic-signal
cell; converting means for converting said
electronic-signal cell into an optical-signal cell
of the wavelength; and means for wavelength-multiplexing said
optical-signal cell and other optical-signal cells
into said wavelength-multiplexed optical signal, wherein, at the destination of said
optical-signal cell, the optical-signal cell is
converted into an electronic-signal cell and the
electronic-signal cell is input into an input port
of the destination.
Claim 23
Independent Claim
98 words
A device in an ATM switch in which a
plurality of stages are interconnected, wherein the
stage has a plurality of basic switches, characterized in that said device converts a
wavelength-multiplexed optical signal including
optical-signal cells which is converted from
electronic-signal cells destined for an input port
into electronic-signal cells and inputs the
electronic-signal cells into the input port, said
device comprising: means for generating a plurality of
optical-signal cells by wavelength-demultiplexing
said wavelength-multiplexed optical signal; means for converting the optical-signal
cells into said electronic-signal cells; and means for inputting said electronic-signal
cells to the input port successively.
Claim 24
Dependent Claim
31 words
The device as claimed in claim 20 or
22, wherein said device includes means for inputting
said electronic-signal cell into said converting
means after converting the speed of said electronic-signal
cell.
References Cited (Backward Citations)
No citation records indexed.
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