Communications system and related method for reducing continuity check message (CCM) bursts in connectivity fault management (CFM) maintenance association (MA)
View Patent ↗In accordance with a non-limiting example, a system and method minimizes collisions between transmitted connectivity fault management (CFM) packets. Maintenance association endpoints are formed from a plurality of network switch elements to form a maintenance association. The clocks between each network switch element within the maintenance association are synchronized. A unique transmission window is assigned to each maintenance association endpoint as part of the maintenance association. A respective CFM packet is transmitted as a continuity check message (CCM) within the unique transmission window.
1. A communications system, comprising:
a plurality of network switch elements each comprising a transceiver and clock and each configured as a Maintenance Association End Point (MEP) and arranged to form a Maintenance Association, wherein each MEP is configured to send periodically a Connectivity Fault Management (CFM) packet as a multicast Continuity Check Message (CCM);
wherein a clock of each network switch element within the Maintenance Association is synchronized with other respective clocks and each MEP is assigned a unique transmission window in the Maintenance Association to transmit from a MEP a respective CFM packet as a CCM.
2. The communications system according to claim 1 , wherein each clock is synchronized using a Network Time Protocol.
3. The communications system according to claim 1 , wherein a respective MEP is configured to determine a transmission window by dividing the CFM packet interval by the maximum number of MEP's in the Maintenance Association.
4. The communications system according to claim 1 , wherein a local MEP is configured to have a unique transmission window at which it is the only MEP in the Maintenance Association transmitting a CCM.
5. The communications system according to claim 1 , wherein a MEP is configured to use an identifier as an index to a list of transmission windows and use the transmission window as an offset against a synchronized timing source.
6. The communications system according to claim 5 , wherein a MEP is configured to apply an offset against a base timing value of a clock.
7. The communications system according to claim 1 , wherein a MEP is configured to determine a transmission window by ordering identifiers of the MEP's in a list and determining which transmission window to use based on the ordering of the MEP identifiers.
8. The communications system according to claim 7 , wherein a MEP is configured to order the identifiers for MEP's in a list and determining which transmission window to use based on an MEP identifier in the list.
9. A method of minimizing collisions between transmitted Connectivity Fault Management (CFM) packets, comprising:
creating a Maintenance Association from a plurality of network switch elements that each comprise a transceiver, processor and clock and correspond each to a respective Maintenance Association End Point (MEP);
synchronizing the clocks between each network switch element within the Maintenance Association;
assigning to each MEP a unique transmission window in the Maintenance Association; and
transmitting from a MEP a respective CFM packet as a Continuity Check Message (CCM) within the unique transmission window.
10. The method according to claim 9 , and further comprising synchronizing the clocks for each of the network switch elements using a Network Time Protocol.
11. The method according to claim 9 , and further comprising determining a transmission window by dividing the CFM packet interval by the maximum number of MEP's in the Maintenance Association.
12. The method according to claim 9 , and further comprising assigning a unique transmission window to a local MEP at which it is the only MEP in the Maintenance Association transmitting a CCM.
13. The method according to claim 9 , wherein a local MEP uses an identifier as an index to a list of transmission windows and using the transmission window as an offset against a synchronized timing source.
14. The method according to claim 13 , and further comprising applying an offset against a base timing value of a clock.
15. The method according to claim 9 , and further comprising determining a transmission window by ordering identifiers of the MEP's in a list and determining which transmission window to use based on the ordering of the MEP identifiers.
16. The method according to claim 15 , and further comprising ordering the identifiers for MEP's in a list and determining which transmission window to use based on an MEP identifier in the list.
17. A method of minimizing collisions between transmitted Connectivity Fault Management (CFM) packets, comprising:
creating a Maintenance Association from a plurality of network switch elements that each comprises a transceiver and clock and correspond each to a respective Maintenance Association End Point (MEP);
determining at a local MEP how many MEP's are active in the Maintenance Association;
creating unique transmission windows;
ordering each MEP by an identifier in a list and determining its position in that list; and
using the position of a respective identifier in the list of MEP's to determine a transmission window to use.
18. The method according to claim 17 , and further comprising taking a continuity check message (CCM) interval and divide it by the number of active MEP's in the Maintenance Association to create unique transmission windows.
19. The method according to claim 17 , and further comprising applying a unique transmission window to a clock base.