Synchronous node controllers for switching network

A synchronized node controller system, which provides an interface between user processors of processor-based communications equipment, and a packet switching network, that uses a first level protocol, comprising:

• a number of gateway interfaces for sending and receiving second level protocol messages to and from a gateway of a switching network;
• a number of cluster processor interfaces for sending and receiving third level protocol messages to and from a cluster of user processors;
• a number of node controllers, each in data communication with a cluster processor interface and a gateway interface, wherein each node controller has:
• a packet data memory for storing packet data during switching by said packet switching network;
• a second level controller for handling the transfer of packet data between said packet data memory and said gateway interface;
• a third level controller for handling the transfer of packet data between said packet data memory and said cluster processor interface;
• a second level first-in first-out (FIFO) memory for storing messages from said gateway interface;
• a third level first-in first-out (FIFO) memory for storing messages from said cluster processor interface;
• a timing unit for receiving a node control synchronization signal, and for using this signal to generate a node control timing signal having a node control frame period that is synchronized to the node control timing signal of other node controllers;
• a packet control processor for receiving said timing signal, and programmed for accessing messages stored in said second level FIFO memory during a first interval of said node control frame period and programmed for accessing messages stored in said third level FIFO memory during a second interval of said node control frame period, and programmed for initiating the operations of said second level controller and said third level controller in accordance with said messages;
• and
• a service request memory for storing packet transfer service requests, and which is accessed by said processor at regular intervals during said node control frame period such that all node controllers process packet transfers synchronously.

A synchronized packet switching network in which messages are communicated in accordance with a first protocol, comprising;

• a number of node controllers, each associated with a cluster processor interface and a gateway interface, wherein each node controller has a packet data memory for storing packet data during switching by said packet switching network;
• a second level controller for handling the transfer of packet data between said packet data memory and said gateway interface;
• a third level controller for handling the transfer of packet data between said packet data memory and said cluster processor interface;
• a second level first-in first-out (FIFO) memory for storing messages from said gateway interface;
• a third level first-in first-out (FIFO) memory for storing messages from said cluster processor interface;
• a timing unit for receiving a node control synchronization signal, and for using this signal to generate a node control timing signal having a node control frame period that is synchronized to the node control timing signal of other node controllers;
• and a packet control processor for receiving said timing signal, and programmed for accessing messages stored in said second level FIFO memory during a first interval of said node control frame period and for accessing messages stored in said third level FIFO memory during a second interval of said node control frame period, and programmed for initiating the operations of second level controller and said third level controller in accordance with said messages;
• a number of gateways, each in communication with a node controller, for receiving requests for service from said node controllers;
• an interchange control system for receiving requests for service from said gateways and for establishing connections in a switching matrix in response to said requests for service;
• an interchange for implementing said switching matrix such that an originating node controller can be connected to a destination node controller;
• node links for connecting said node controllers to said gateways;
• request and response links for connecting said gateways to said interchange control system;
• and
• packet transport links for connecting said gateways to said interchange.

A method of interfacing a packet switching network to a number of user processors that handle communications of data at an origin and a destination and that are organized into groups, each group associated with a node controller, said switching network using a first level protocol for establishing and releasing connections, comprising the steps of:

• using a second level protocol to handle messages between said node controllers;
• using a third level protocol to handle communications between said user processors;
• storing messages associated with said second level protocol in a second level memory of each of said node controllers;
• storing messages associated with said third level protocol in a third level memory of each of said node controllers;
• processing said second level memory;
• processing said third level memory;
• wherein each of said processing steps are performed in synchronization by all of said node controllers during a node control frame.

A method of synchronizing the operation of a switching network that handles communications for processor-based user equipment and that uses a first level protocol to handle communications related to a switching matrix, comprising the steps of:

• using node controllers, each associated with a cluster of user processors, to handle a second level protocol for messages between said node controllers and to handle a third level protocol for messages between user processors;
• receiving a node controller synchronization signal at each of said node controllers;
• defining a node control frame period with said node control synchronization signal;
• performing processes associated with said second level protocol and said third level protocol during said node control frame, such that each node controller performs the same schedule of processes during said node control frame period;
• defining a packet frame within said node control frame;
• and
• performing packet transfers within said packet frame.