Claims Analysis
Total Claims: 12
Claim 1
Independent Claim
235 words
A node for a fast packet-switching network in optical-electrical technology, wherein the switching takes place on the basis of routing information contained in a header of each packet, characterized in that it comprises: - an optical switching matrix (MOT), comprising a plurality of stages, each comprising a plurality of switching elements, for switching information packets transmitted as optical signals; - an electrical switching matrix (MEL), which is used for searching a routing through the node (NL1...NLn, NT1...NTn) by exploiting information contained in the headers of the information packets and converted into electrical form, the configuration taken by the electrical switching matrix (MEL) being reproduced in the optical switching matrix (MOT); - a first group of processing devices (PEE), associated with the inputs of the electrical switching matrix (MEL), for the electrical processings of information packet headers necessary to search for a connection path between an input and an output of the electrical switching matrix (MEL) and for updating the headers in the optical information packets; - a second group of electrical processing devices (PUE), associated with the outputs of the electrical switching matrix (MEL), for recognizing that a connection has been set up between an input and an output of the electrical switching matrix (MEL) and forwarding a packet acknowledging such a setup to the processing devices (PEE) of the first group; - a centralized node controller (CEL), for the electrical processing of signalling packets.
Claim 2
Dependent Claim
235 words
A node for a fast packet-switching network in optical-electrical technology, wherein the switching takes place on the basis of routing information contained in a header of each packet, characterized in that it comprises: - an optical switching matrix (MOT), comprising a plurality of stages, each comprising a plurality of switching elements, for switching information packets transmitted as optical signals; - an electrical switching matrix (MEL), which is used for searching a routing through the node (NL1...NLn, NT1...NTn) by exploiting information contained in the headers of the information packets and converted into electrical form, the configuration taken by the electrical switching matrix (MEL) being reproduced in the optical switching matrix (MOT); - a first group of processing devices (PEE), associated with the inputs of the electrical switching matrix (MEL), for the electrical processings of information packet headers necessary to search for a connection path between an input and an output of the electrical switching matrix (MEL) and for updating the headers in the optical information packets; - a second group of electrical processing devices (PUE), associated with the outputs of the electrical switching matrix (MEL), for recognizing that a connection has been set up between an input and an output of the electrical switching matrix (MEL) and forwarding a packet acknowledging such a setup to the processing devices (PEE) of the first group; - a centralized node controller (CEL), for the electrical processing of signalling packets.
Claim 3
Dependent Claim
37 words
A node according to claim 1, characterized in that the electrical switching matrix (MEL) comprises the same number of stages and the same number of elements as the optical switching matrix (MOT) and is topologically identical thereto.
Claim 4
Dependent Claim
83 words
A node according to claim 1 or 2, characterized in that each input of the optical switching matrix (MOT) is associated with an optical buffer (BOT) for temporarily storing the packets to be optically switched for the time necessary to search for and set up a connection path between an input and an output of the electrical switching matrix (MEL) and to set up the optical switching matrix (MOT), the packets stored in all buffers (BOT) being read at a same time instant.
Claim 5
Dependent Claim
69 words
A node according to claim 1 or 2, characterized in that said processing devices (PEE) of the first group are connected to the centralized controller (CEL) from which they receive information necessary to update the information packet header and to build therein a routing tag for the routing through the electrical switching matrix (MEL), the header updating being effected directly in the optical packets contained in said buffers (BOT).
Claim 6
Dependent Claim
64 words
A node according to claim 1 or 2, characterized in that a memory (MPM) is connected between the electrical and the optical switching matrix (MEL, MOT), to store information, under electrical signal form, indicating the configuration taken by the elements of the electrical switching matrix (MEL), said information being transferred to the homologous elements of the optical switching matrix (MOT) as a setting command.
Claim 7
Dependent Claim
35 words
A node according to any preceding claim, characterized in that it comprises synchronization means (SIN1, SIN2) for extracting from the arriving packet flow timing signals (CKE1, CKE2) for packet acquisition by the node (NL1i...NLnj, NT1...NTn).
Claim 8
Dependent Claim
153 words
A node according to any preceding claim, characterized in that it comprises a local time base (BT) generating timing signals (CKL1, CKL2, CKL3, RC, R, T) for the various devices in the node (NL1i...NLnj, NT1...NTn) and organizing the switching operations in the node (NL1i...NLnj, NT1...NTn) into working cycles, of constant duration, comprising a first phase wherein the electrical switching matrix (MEL) is set and the headers of the packets present in the optical buffers (BOT) are updated, a second phase in which the optical switching matrix (MOT) is set and the processing devices (PUE) of the second group send towards the processing devices (PEE) of the first group possible packets acknowledging that a connection has been established between a node input and output, and a third phase in which optical packets for which a routing path through the node has been found are forwarded through the optical matrix (MOT) towards the node outputs.
Claim 9
Dependent Claim
32 words
A node according to any preceding claim, characterized in that signalling packets and information packets present on a same input/output line of the node (NL1i..NLnj, NT1...NTn) are transmitted by using different wavelengths.
Claim 10
Dependent Claim
89 words
A node according to claim 8, characterized in that input/output lines of the node, which convey both packet types, are associated with means (WD, SEP) for recognizing information packets and signalling packets and sending the former towards the optical switching matrix (MOT) and the first group of processing devices (PEE), and the latter towards the centralized controller (CEL), and respectively with means for recombining the packets switched by the optical matrix (MOT) and the signalling packets emitted by the centralized controller (CEL) into a single flow of optical packets.
Claim 11
Dependent Claim
82 words
A node according to claims 6 and 8, characterized in that the synchronization means comprises a first synchronization device (SIN1) for recognizing the beginning of each signalling packet and extracting from the signalling packet flow timing signals (CKE1, IN1) for signalling packet acquisition by the node (NL1i...NLnj, NT1...NTn), and a second synchronization device (SIN2), for recognizing the beginning of each information packet and extracting from the information packet flow timing signals (CKE2, IN2) for information packet acquisition by the node (NL1i...NLnj, NT1...NTn).
Claim 12
Dependent Claim
27 words
A node according to claim 7, characterized in that information and signalling packets present on a same input/output line of the node are transmitted at different speeds.