Method and system for coordination of admission control in transport networks

A method of coordinating admission control messages across multiple transport network domains for performance by a coordinator entity acting for a local subset of one or more of the transport network domains, the method comprising the steps:—

• i) receiving at least one coordination request message containing admission control request information;
• ii) forwarding an admission control request message containing the admission control request information towards an admission control interface or functions of the subset of one or more of the transport network domains;
• iii) receiving an admission control response message containing local admission control response information derived from admission control responses of the or each of the local subset of transport network domains made in response to the admission control request information;
• iv) generating a further coordination message in dependence on at least the admission control response information;
• and
• v) transmitting the further coordination message;
• wherein a hierarchy of coordinator entities are provided of which the coordinator entity acting for the local subset of transport network domains forms a part, the hierarchy comprising a lowest layer of coordinator entities each of which acts for a single transport network domain, and one or more higher layers of coordinators, a coordinator in a higher layer acting to exchange messages with coordinators in the next lower layer, whereby to aggregate admission control responses from the multiple transport network domains.

A method of coordinating admission control signals across multiple transport network domains, comprising:

• providing, for a transport network domain, at least one coordinator entity arranged to exchange admission control request and response messages with an admission control interface of the transport network domain for which it was provided;
• and
• exchanging coordination request and response messages between the coordinator entities of the multiple transport network domains to combine the admission control responses of the domains;
• wherein the coordinator entity operates in a non-blocking mode, wherein a received coordination request message containing an admission control request is forwarded on to a next coordinator entity for a next-hop transport network domain prior to an admission control response being obtained from the network domain for which the coordinator entity acts;
• wherein for a received coordination request message containing an admission control request an admission control response is obtained from the network domain for which the coordinator entity acts, which response is combined with an admission control response received in a coordination response message from the next coordinator entity for a next-hop transport network domain;
• wherein the coordination response message is then forwarded to a previous coordinator entity for a previous-hop transport network domain.

A method of coordinating admission control signals across multiple transport network domains, comprising:

• providing, for a transport network domain, at least one coordinator entity arranged to exchange admission control request and response messages with an admission control interface of the transport network domain for which it was provided;
• and
• exchanging coordination request and response messages between the coordinator entities of the multiple transport network domains to combine the admission control responses of the domains;
• wherein the coordinator entity operates in a blocking mode, wherein for a received coordination request message containing an admission control request an admission control response is obtained from the network domain for which the coordinator entity acts, which response is combined with the admission control request before the coordination request message is forwarded on to a next coordinator entity for a next-hop transport network domain
• wherein the combining step further comprises:
• comparing the admission control response with one of:
• i) in blocking mode, the admission control request information;
• or
• ii) in non-blocking mode, the admission control response information received in the coordination response message;
• determining that information of the compared information which represents the minimum of the two;
• and
• producing the further coordination message containing admission control request or response information corresponding to the determined minimum information.

A coordinator system for coordinating admission control messages across multiple transport network domains, the coordinator system acting for a local subset of one or more of the transport network domains, the system comprising:—

• a message interface arranged in use to:
• i) receive at least one coordination request message containing admission control request information;
• ii) forward an admission control request message containing the admission control request information towards an admission control interface or functions of the subset of one or more of the transport network domains;
• and
• iii) receive an admission control response message containing local admission control response information derived from admission control responses of the or each of the local subset of transport network domains made in response to the admission control request information;
• a control element arranged in use to:
• i) generate a further coordination message in dependence on at least the admission control response information;
• the message interface being further arranged in use to:
• iv) transmit the further coordination message;
• wherein the coordinator system acts in a non-blocking mode, wherein the message interface, after receiving the at least one coordination request message, forwards the coordination request message to a next hop coordinator entity acting for a next neighbouring subset of one or more transport network domains;
• wherein message interface is further arranged in use to receive a coordination response message containing admission control response information from the next hop coordinator entity, the control element then generating, as the further coordination message, a coordination response message containing admission control response information generated in dependence on the local admission control response information and the received admission control response information, the message interface then transmitting the coordination response message;
• and
• wherein the coordination response message is transmitted to a previous hop coordinator entity acting for a previous neighbouring subset of one or more transport network domains.

A coordinator system for coordinating admission control messages across multiple transport network domains, the coordinator system acting for a local subset of one or more of the transport network domains, the system comprising:

• a message interface arranged in use to:
• i) receive at least one coordination request message containing admission control request information;
• ii) forward an admission control request message containing the admission control request information towards an admission control interface or functions of the subset of one or more of the transport network domains;
• and
• iii) receive an admission control response message containing local admission control response information derived from admission control responses of the or each of the local subset of transport network domains made in response to the admission control request information;
• a control element arranged in use to:
• i) generate a further coordination message in dependence on at least the admission control response information:
• the message interface being further arranged in use to:—
• iv) transmit the further coordination message;
• wherein the coordinator system acts in a blocking mode wherein the control element generates, as the further coordination message, a further coordination request message in dependence on the local admission control response information and the received admission control request information, and the message interface transmits the further coordination request message to a next hop coordinator entity acting for a next neighbouring subset of one or more transport network domains;
• and
• wherein the control element is further arranged in use to:—
• compare the local admission control response information with one of:—
• i) in blocking mode, the admission control request information;
• or
• ii) in non-blocking mode, the admission control response information received in the coordination response message;
• determine that information of the compared information which represents the minimum of the two;
• and
• produce the further coordination message containing admission control request or response information corresponding to the determined minimum information.

A coordinator system for coordinating admission control messages across multiple transport network domains, the coordinator system acting for a local subset of one or more of the transport network domains, the system comprising:

• a message interface arranged in use to:
• i) receive at least one coordination request message containing admission control request information:
• ii) forward an admission control request message containing the admission control request information towards an admission control interface or functions of the subset of one or more of the transport network domains;
• and
• iii) receive an admission control response message containing local admission control response information derived from admission control responses of the or each of the local subset of transport network domains made in response to the admission control request information;
• a control element arranged in use to:—
• i) generate a further coordination message in dependence on at least the admission control response information;
• the message interface being further arranged in use to:
• iv) transmit the further coordination message;
• wherein a hierarchy of coordinator entities are provided of which the coordinator system acting for the local subset of transport network domains forms a part, the hierarchy comprising a lowest layer of coordinator entities each of which acts for a single transport network domain, and one or more higher layers of coordinators, a coordinator in a higher layer acting to exchange messages with coordinators in the next lower layer, whereby to aggregate admission control responses from the multiple transport network domains.

A system of coordinating admission control signals across multiple transport network domains, comprising:

• at least one coordinator entity provided for a transport network domain and arranged to exchange admission control request and response messages with an admission control interface of the transport network domain for which it was provided;
• the coordinator entity being further arranged to exchange coordination request and response messages with other coordinator entities of the multiple transport network domains to combine the admission control responses of the domains;
• wherein the coordinator entity operates in a non-blocking mode, wherein a received coordination request message containing an admission control request is forwarded on to a next coordinator entity for a next-hop transport network domain prior to an admission control response being obtained from the network domain for which the coordinator entity acts;
• wherein for a received coordination request message containing an admission control request an admission control response is obtained from the network domain for which the coordinator entity acts, which response is combined with an admission control response received in a coordination response message from the next coordinator entity for a next-hop transport network domain;
• and
• wherein the coordination response message is then forwarded to a previous coordinator entity for a previous-hop transport network domain.

A system of coordinating admission control signals across multiple transport network domains, comprising:

• at least one coordinator entity provided for a transport network domain and arranged to exchange admission control request and response messages with an admission control interface of the transport network domain for which it was provided;
• the coordinator entity being further arranged to exchange coordination request and response messages with other coordinator entities of the multiple transport network domains to combine the admission control responses of the domains;
• wherein the coordinator entity operates in a blocking mode, wherein for a received coordination request message containing an admission control request an admission control response is obtained from the network domain for which the coordinator entity acts, which response is combined with the admission control request before the coordination request message is forwarded on to a next coordinator entity for a next-hop transport network domain;
• wherein the coordinator entity combines the admission control responses by:
• comparing the admission control response of the network domain for which it acts with one of:—
• i) in blocking mode, the admission control request information;
• or
• ii) in non-blocking mode, the admission control response information received in the coordination response message;
• determining that information of the compared information which represents the minimum of the two;
• and
• producing the further coordination message containing admission control request or response information corresponding to the determined minimum information.