Time synchronized resource reservation over packet switched networks

1. A method for scheduling reservations of resources in a packet-switched communication network including end-nodes and core network switches, said method comprising:

receiving a resource advertising message including a timestamp advertising a time at which a stream would be provided by a node which sent the resource advertising message;

including time information for each resource reservation request, issued by an end-node and forwarded, at a data link layer, by at least one core network switch, and requesting a resource reservation for receiving the stream at a time which is represented by said time information, said resource reservation scheduling being handled at a data link layer of an Open Systems Interconnection (OSI) model, said resource reservation request also including a time to release requested resources;

storing said time information, included into each forwarded end-node request in correspondence with associated stream specifications, into at least one related database managed by a core network switch participating in said resource reservation request forwarding; and

after receiving the stream from the advertising node, forwarding the received stream to the end node which requested the stream at the time that was included in the resource reservation message.

2. The method according to claim 1 , wherein said time information is derived from a time given by a clock shared by said end-nodes and core network switches.

3. The method according to claim 1 , wherein said time information is added to a multiple stream registration protocol data unit, which constitutes an end-node request complying with IEEE 802.1Qat standard, into a new dedicated field.

4. The method according to claim 3 , wherein said new dedicated field is added to a sub-branch of said multiple stream registration protocol data unit, named “First Value”, in parallel with a field named “StreamID” which defines an identifier of a stream.

5. A method for scheduling reservations of resources in a packet-switched communication network including end-nodes and core network switches, said method comprising:

receiving a resource advertising message including a timestamp advertising a time at which a stream would be provided by an end-node which sent the resource advertising message;

receiving time information for each resource reservation request, issued by an end-node and forwarded by at least one core network switch, and requesting a resource reservation for receiving the stream at a time which is represented by said time information, said resource reservation messages being handled at a data link layer of an Open Systems Interconnection (OSI) model;

storing said time information, included in each forwarded end-node resource reservation request in correspondence with associated stream specifications, into a database managed by a core network switch participating in said resource reservation request forwarding;

inspecting said stored information to ensure resource availability before accepting receipt of the stream from the advertising end-node and forwarding the received stream to the end-node which requested the stream at the time that was included in the resource reservation request.

6. The method according to claim 5 , wherein said time information is derived from a time given by a clock shared by said end-nodes and core network switches.

7. The method according to claim 5 , wherein said time information is added to a multiple stream registration protocol data unit, which constitutes an end-node request complying with IEEE 802.1Qat standard, into a new dedicated field.

8. The method according to claim 7 , wherein said new dedicated field is added to a sub-branch of said multiple stream registration protocol data unit, named “First Value”, in parallel with a field named “StreamlD” which defines an identifier of a stream.

9. A method for scheduling reservations of resources in a packet-switched communication network including a plurality of nodes, said method comprising:

receiving a resource advertising message including a timestamp advertising a time at which a stream would be provided by a first node which sent the resource advertising message;

receiving time information for each resource reservation request, issued by a second node and forwarded by at least one third node, and requesting a resource reservation for receiving the stream at a time which is represented by said time information, said resource reservation messages being handled at a data link layer of an Open Systems Interconnection (OSI) model;

storing said time information, included in each forwarded second node resource reservation request in correspondence with associated stream specifications, into a database managed by a third node participating in said resource reservation request forwarding;

inspecting said stored information to ensure resource availability before accepting receipt of the stream from the advertising first node and forwarding the received stream to the second node which requested the stream at the time that was included in the resource reservation request.

10. The method according to claim 9 , wherein said time information is derived from a time given by a clock shared by said plurality of nodes.

11. The method according to claim 9 , wherein said time information is added to a multiple stream registration protocol data unit, which constitutes a second node request complying with IEEE 802.1Qat standard, into a new dedicated field.

12. The method according to claim 11 , wherein said new dedicated field is added to a sub-branch of said multiple stream registration protocol data unit, named “First Value”, in parallel with a field named “StreamlD” which defines an identifier of a stream.