Distributed switching system

A distributed switching system comprising:

• a plurality of nodes coupled together at physical medium dependent sublayers thereof to form a ring wherein each of said nodes receives incoming data from a first adjacent one of said nodes and transmits outgoing data to a second adjacent one of said nodes, one of said nodes being designated as a ring master node;
• means, coupled to said physical medium dependent sublayer at said ring master node, for delaying outgoing data transmitted from said ring master node relative to incoming data received at said ring master node;
• means for controlling said delaying means to maintain a constant quantity of data circulating in said ring wherein said constant quantity of data is an integral number of frames;
• means, coupled to said physical medium dependent sublayer within each of said nodes, for dedicating a first portion of each of said frames to a random access service;
• means, coupled to said physical medium dependent sublayer within each of said nodes, for dedicating a second portion of each of said frames to a deterministic access service;
• means, coupled to said physical medium dependent sublayer within a first one of said nodes, for receiving a circulating message transmitted from said first adjacent node for said first one of said nodes using a random access service and for determining if said circulating message is destined for said first one of said nodes;
• and
• means, coupled to said physical medium dependent sublayer in said first one of said nodes, for transmitting one of said circulating message and a new message to said second adjacent node from said first one of said nodes using said random access service;
• said transmitting means comprising means, coupled to said receiving means, for transmitting said circulating message received at said receiving means when said circulating message is not destined for said first one of said nodes and for transmitting said new message and not transmitting said circulating message when said transmission of said new message begins prior to reception of said circulating message.

A distributed switching system comprising:

• a plurality of nodes coupled together at physical medium dependent sublayers thereof to form a ring wherein each of said nodes receives incoming data from a first adjacent one of said nodes and transmits outgoing data to a second adjacent one of said nodes, one of said nodes being designated as a ring master node;
• means, coupled to said physical medium dependent sublayer at said ring master node, for delaying said outgoing data transmitted from said ring master node relative to said incoming data received at said ring master node;
• means for controlling said delaying means to maintain a constant quantity of said incoming and outgoing data circulating in said ring wherein said constant quantity of data forms an integral number of frames;
• and
• means, coupled to said physical medium dependent sublayer within each of said nodes, for dividing each of said frames into a first portion thereof which includes a plurality of independent cells wherein each of said cells contains control information to specify one of a plurality of distinct deterministic access services to which said cells are dedicated.

A distributed switching system comprising:

• a plurality of nodes coupled together at physical medium dependent sublayers thereof to form a ring wherein each of said nodes receives incoming data from a first adjacent one of said nodes and transmits outgoing data to a second adjacent one of said nodes, one of said nodes being designated as a ring master node;
• means, coupled to said physical medium dependent sublayer at said ring master node, for delaying said outgoing data transmitted from said ring master node relative to said incoming data received at said ring master node;
• means for controlling said delaying means to maintain a constant quantity of said incoming and outgoing data circulating in said ring wherein said constant quantity of data forms an integral number of frames;
• means, coupled to said physical medium dependent sublayer within each of said nodes, for dividing each of said frames into a first portion thereof which includes a plurality of independent cells wherein each of said cells contains control information to specify one of a plurality of distinct deterministic access services to which said cells are dedicated and into a second portion thereof which is dedicated to a random access service;
• means, coupled to said physical medium dependent sublayer within each of said nodes, for identifying a predetermined instant within each of said frames;
• means, coupled to said identifying means, for counting the occurrence of said incoming data from said predetermined instant to distinguish one cell from another cell within said frames;
• and
• means, coupled to said counting means within at least one of said nodes, for decoding a control field of each cell to determine if cells are marked for removal from service and for decoding said control field to determine if cells provide one of circuit switching, cell switching, and packet switching deterministic access services.

A method of switching data in a distributed switching system having a plurality of nodes coupled together at physical medium dependent sublayers thereof to form a ring wherein each of said nodes receives data from a first adjacent one of said nodes and transmits data to a second adjacent one of said nodes, said method comprising the steps of:

• delaying outgoing data transmitted from a ring master one of said nodes relative to incoming data received at said ring master node;
• controlling the duration of delay in said delaying step to maintain a constant quantity of incoming and outgoing data circulating in said ring wherein said constant quantity of data forms an integral number of frames;
• dividing each of said frames into first and second portions wherein said first portions are dedicated to a random access service;
• and
• dedicating said second portions to a deterministic access service.

A method of switching data in a switching system having a plurality of nodes coupled together to form a ring wherein each of said nodes receives incoming data from a first adjacent one of said nodes and transmits outgoing data to a second adjacent one of said nodes, said method comprising the steps of:

• delaying said outgoing data transmitted from one of said nodes relative to said incoming data received at said one node;
• controlling the duration of delay in said delaying step to maintain a constant quantity of said incoming and outgoing data circulating in said ring wherein said constant quantity of data is an integral number of frames;
• and
• dedicating a first portion of each of said frames to having a plurality of independent cells wherein each of said cells specifies one of a plurality of distinct deterministic access services to which said cell is dedicated.

A distributed switching system comprising:

• a plurality of nodes coupled together at physical medium dependent sublayers thereof to form a ring wherein each of said nodes receives incoming data from a first adjacent one of said nodes and transmits outgoing data to a second adjacent one of said nodes, one of said nodes designated as a ring master node;
• means, coupled to said physical medium dependent sublayer at said ring master node, for delaying outgoing data transmitted from said ring master node relative to incoming data received at said ring master node;
• means for controlling said delaying means to maintain a constant quantity of data circulating in said ring wherein said constant quantity of data is an integral number of frames;
• means, coupled to said physical medium dependent sublayer within each of said nodes, for dedicating a first portion of each of said frames to a random access service;
• means, coupled to said dedicating means in a first one of said nodes, for receiving a circulating message transmitted from said first adjacent node for said first one of said nodes using said random access service and for determining if said circulating message is destined for said first one of said nodes;
• and
• means, coupled to said dedicating means in said first one of said nodes, for transmitting one of said circulating message and a new message to said second adjacent node for said first one of said nodes using said random access service;
• said transmitting means comprising means coupled to said receiving means, for transmitting said circulating message received at said receiving means when said circulating message is not destined for said first one of said nodes and for transmitting said new message and not transmitting said circulating message when said transmission of said new message begins prior to reception of said circulating message.

A method of switching data in a distributed switching system having a plurality of nodes coupled together at physical medium dependent sublayers thereof to form a ring wherein each of said nodes receives data from a first adjacent one of said nodes and transmits data to a second adjacent one of said nodes, said method comprising the steps of:

• delaying outgoing data transmitted from a ring master one of said nodes relative to incoming data received at said ring master node;
• controlling the duration of delay in said delaying step to maintain a constant quantity of incoming and outgoing data circulating in said ring wherein said constant quantity of data forms an integral number of frames;
• dividing each of said frames into first and second portions wherein said first portions are dedicated to a random access service;
• receiving, at a first one of said nodes, a circulating message transmitted from said first adjacent node for said first one of said nodes using said random access service;
• and
• transmitting, from said first one of said nodes, one of said circulating message and a new message to said second adjacent node for said first one of said nodes using said random access service, wherein said circulating message received in said receiving step is transmitted when said circulating message is not destined for said first node and wherein said new message and not said circulating message is transmitted when said new message begins prior to receipt of said circulating message.

A method of switching data in a distributed switching system having a plurality of nodes coupled together at physical medium dependent sublayers thereof to form a ring wherein each of said nodes receives data from a first adjacent one of said nodes and transmits data to a second adjacent one of said nodes, said method comprising the steps of:

• delaying outgoing data transmitted from a ring master one of said nodes relative to incoming data received at said ring master node;
• controlling the duration of delay in said delaying step to maintain a constant quantity of incoming and outgoing data circulating in said ring wherein said constant quantity of data forms an integral number of frames;
• dividing each of said frames into first and second portions wherein said first portions are dedicated to a random access service;
• and
• dedicating said second portions to a deterministic access service.