Congestion Notification Element and Method for Congestion Control

Abstract

A congestion notification element for indicating a congestion status of a mesh node may include at least one field specifying a mesh destination for which an intra-mesh congestion control is to be applied. This may allow for forwarding data frames on paths that share some links but not the bottleneck link with a path that is congestion controlled, which has not been possible with currently specified congestion notification techniques.

What is claimed is: 
     
         1 . A congestion notification element for indicating a congestion status of a mesh node in a mesh network, the congestion notification element comprising:
 at least one field specifying a mesh destination for applying an intra-mesh congestion control.   
     
     
         2 . Congestion notification element according to  claim 1 , wherein the mesh destination is determined by an address of a destination mesh node. 
     
     
         3 . Congestion notification element according to  claim 1 , wherein the mesh destination is determined by a broadcast address. 
     
     
         4 . Congestion notification element according to  claim 1 , further comprising field specifying a number of fields, each specifying a respective mesh destination. 
     
     
         5 . Congestion notification element according to  claim 1 , comprising at least one congestion notification, each congestion notification including
 one of the at least one field specifying the mesh destination,   at least one field specifying a congestion notification expiration timer, and   a field specifying a number of congestion notifications included in the congestion notification element.   
     
     
         6 . A congestion control notification frame, Comprising:
 at least one congestion notification element, each congestion notification element comprising:
 at least one field specifying a mesh destination for applying an intra-mesh congestion control. 
   
     
     
         7 . A congestion control notification frame according to  claim 6 , comprising fields defined by IEEE P802.11s. 
     
     
         8 . A method of controlling congestion in a mesh network, the method comprising:
 receiving at a receiving mesh node from a transmitting mesh node at least one congestion control notification frame including at least one congestion notification element;   reading at least one transmitter mesh node address of said at least one congestion control notification frame as a next hop address;   reading at least one destination mesh node address of said at least one congestion notification element, said destination mesh node address being an individual address or a broadcast address; and   reading at least one congestion notification expiration timer of said at least one congestion notification element.   
     
     
         9 . The method according to  claim 8 , comprising:
 receiving at said receiving mesh node a data frame including a destination address of said data frame;   reading the destination address of said data frame; and   reading a next hop address for the destination address of said data frame from a forwarding information.   
     
     
         10 . The method according to  claim 9 , comprising:
 postponing a forwarding of said data frame by said receiving node for a case in which said next hop address for said data frame is equal to at least one next hop address from said at least one congestion control notification frame;   wherein said destination address of said data frame is equal to at least one destination mesh node address from said at least one next hop address of said at least one congestion notification element.   
     
     
         11 . The method according to  claim 9 , comprising:
 postponing a forwarding of said data frame by said receiving node for a case in which said next hop address for said data frame is equal to at least one next hop address from said at least one congestion control notification frame;   wherein at least one destination mesh node address from said at least one next hop address of said at least one congestion notification element is equal to said broadcast address.   
     
     
         12 . The method according to  claim 10 , wherein said postponing of said forwarding of said data frame is performed until a corresponding congestion notification expiration timer of a corresponding access category has expired. 
     
     
         13 . A mesh node in a mesh network comprising non-transitory computer-readable media storing instructions executable by a processor to:
 receive from a transmitting mesh node at least one congestion control notification frame including at least one congestion notification element;   read at least one transmitter mesh node address of said at least one congestion control notification frame as a next hop address;   read at least one destination mesh node address of said at least one congestion notification element, said destination mesh node address being an individual address or a broadcast address; and   read at least one congestion notification expiration timer of said at least one congestion notification element.   
     
     
         14 - 17 . (canceled) 
     
     
         18 . The mesh node according to  claim 13 , wherein the instructions are further executable to:
 receive at said mesh node a data frame including a destination address of said data frame;   read the destination address of said data frame; and   read a next hop address for the destination address of said data frame from a forwarding information.   
     
     
         19 . The mesh node according to  claim 18 , wherein the instructions are further executable to:
 postpone a forwarding of said data frame by said receiving node for a case in which said next hop address for said data frame is equal to at least one next hop address from said at least one congestion control notification frame;   wherein said destination address of said data frame is equal to at least one destination mesh node address from said at least one next hop address of said at least one congestion notification element.   
     
     
         20 . The method according to  claim 18 , wherein the instructions are further executable to:
 postpone a forwarding of said data frame by said receiving node for a case in which said next hop address for said data frame is equal to at least one next hop address from said at least one congestion control notification frame;   wherein at least one destination mesh node address from said at least one next hop address of said at least one congestion notification element is equal to said broadcast address.   
     
     
         21 . The mesh node according to  claim 19 , wherein said postponing of said forwarding of said data frame is performed until a corresponding congestion notification expiration timer of a corresponding access category has expired.