Traffic management in packet communications networks

Claim 2

A packet communications network including a plurality of switching nodes interconnected by transmission links, and in which data packets are transmitted over multilink paths between a source node and a destination node, said data packets each belonging to one of a plurality of classes of traffic, said packet communications network comprising means for storing, at each said node, a representation of the traffic load reserved for those connections in each of said plurality of classes of traffic to be transmitted on each of said transmission links terminating at said node, means for initiating a new connection in said network by propagating a a connection request along the route selected for that connection, each said connection request including a vector representing the characteristics of said new connection, and means responsive to said connection request for updating said representations of traffic load for the class of traffic of said connection request and for all lower classes of traffic, said updating taking place by vector addition at each of said nodes along said route.

Claim 3

The packet communications network according to claim 1 further comprising means responsive to said connection request for denying said connection request when the updated representation of the traffic load for any class of traffic on any of said transmission links exceeds the reservable capacity of said transmission link.

Claim 4

The packet communications network according to claim 1 wherein said classes of traffic comprise classes of priorities in forwarding said packets through said network.

Claim 5

The packet communications network according to claim 3 wherein said classes of priorities include real-time and non-real time information.

Claim 6

The packet communications network according to claim 1 wherein said means for updating said representations of link traffic load for a new connection i of traffic class I comprises means for determining the value t1 of a first variable given by where R(link) is the maximum reservable traffic capacity on the link, N * (I) is a constant for traffic class I representing the number of connections with metrics similar to the metrics of connection i which could be statistically multiplexed on the capacity R(link), and m(i) is the mean of the bit rate for said new connection i, means for comparing the value of said first variable to zero and, if said value is greater than zero, determining the value t2 of a second variable given by where α(ñ is the standard deviation of the mean bit rate m(i), and a' is given by means for comparing the value of said second variable to the square of said first variable, means for determining an update vector (i,l) in which the variance of the bit rate is zero, means for updating said representation with said request vector when said first variable is greater than zero and said second variable is less than the square of said first variable, and means for updating said representation with said update vector (i,l) otherwise.

Claim 9

The method according to claim 6 further comprising the step of denying, in response to said connection request, said connection request when the updated representation of the traffic load for any class of traffic on any of said transmission links exceeds the reservable capacity of said transmission link.

Claim 10

The method according to claim 6 wherein said classes of traffic comprise classes of priorities in forwarding said packets through said network.

Claim 11

The method according to claim 8 wherein said classes of priorities include real-time and non-real time information.

Claim 12

The method according to claim 6 wherein said step of updating said representations of link traffic for a new connection i of traffic class I comprises determining the value t(1) of a first variable given by where R(link) is the maximum reservable traffic capacity on said link, N * (I) is a constant for traffice class I representing the number of connections with metrics similar to the metrics of connection i which could be statistically multiplexed on the capacity R(link), and m(i) is the mean of the bit rate for said new connection i, comparing the value of said first variable to zero and, if said value is greater than zero, determining the value t2 of a second variable given by where σ(i) is the standard deviation of the mean bit rate m(i),and a'(I) is given by comparing the value of said second variable to the square of said first variable, determining an update vector r (i,l) in which the variance of the bit rate is zero, updating said representation with said request vector when said first variable is greater than zero and said second variable is less than the square of said first variable, and updating said representation with said update vector r (i,n otherwise.

Claim 13

A node for a packet communications network including a plurality of switching nodes interconnected by transmission links, and in which data packets are transmitted over multilink paths between a source node and a destination node, said data packets belonging to one of a plurality of classes of traffic, said packet communications network node comprising means for storing at said node a representation of the traffic load reserved for those connections in each of said plurality of classes of traffic to be transmitted on each transmission link terminating in said node, means for initiating a new connection from said node into said network by propagating a connection request from said node along the route selected for that connection, each said connection request including a vector representing the characteristics of said new connection, and means in said node responsive to a connection request from other nodes in said network for updating said representation of traffic load for the class of traffic of said connection request and for all lower classes of traffic, said updating taking place by vector addition at said node.

Claim 14

A node for a packet communications network including a plurality of switching nodes interconnected by transmission links, and in which data packets are transmitted over multilink paths between a source node and a destination node, said data packets belonging to one of a plurality of classes of traffic, said packet communications network node comprising means for storing at said node a representation of the traffic load reserved for those connections in each of said plurality of classes of traffic to be transmitted on each transmission link terminating in said node, means for initiating a new connection from said node into said network by propagating a connection request from said node along the route selected for that connection, each said connection request including a vector representing the characteristics of said new connection, and means in said node responsive to a connection request from other nodes in said network for updating said representation of traffic load for the class of traffic of said connection request and for all lower classes of traffic, said updating taking place by vector addition at said node.

Claim 15

The packet communications network node according to claim 11 further comprising means responsive to said connection request for denying said connection request when the updated representation of the traffic load for any class of traffic on a transmission link in said route exceeds the capacity of said transmission link.

Claim 16

The packet communications network node according to claim 11 wherein said classes of traffic comprise classes of priorities in forwarding said packets through said network.

Claim 17

The packet communications network node according to claim 13 wherein said classes of priorities include real-time and non-real-time information.

Claim 18

The packet communications network node according to claim 11 wherein said means for updating said representations of traffic load for a new connection i of traffic class I comprises means for determining the value t1 of a first variable given by where R(link) is the maximum reservable traffic capacity on said link, N * (I) is a constant for traffic class I representing the number of connections with metrics similar to the metrics of connection i which could be statistically multiplexed on the capacity R(link), and m(i) is the mean of the bit rate for said new connection, means for comparing the value of said first variable to zero and, if said value is greater than zero, determining the value t2 of a second variable given by where σ(i) is the standard deviation of the mean bit rate m(i), and α'(l) is given by means for comparing the value of said second variable to the square of said first variable, means for determining an update vector r (i,n in which the variance of the bit rate is zero, means for updating said representation with said request vector when said first variable is greater than zero and said second variable is less than the square of said first variable, and means for updating said representation with said update vector (i,l) otherwise.