System and method for mapping quality of service levels between MPLS and ATM connections in a network element

A translation module for a network element, said translation module translating at least one ATM quality of service (QoS) parameter related to an ATM transmission protocol from said ATM transmission protocol to a MPLS transmission protocol for an ATM cell being sent on a connection from an ATM communication network utilizing said ATM transmission protocol to a MPLS conununication network utilizing said MPLS transmission protocol, said network element connected to said ATM communication network and said MPLS communication network, said network element receiving said ATM cell from said ATM communication network and communicating said ATM cell to said translation module, said network element transmitting said ATM cell from said network element over said MPLS communication network after translation of said at least one ATM QoS parameter, said translation module comprising:

• a control complex for mapping said at least one ATM QoS parameter to a MPLS class of service value for said connection;
• a MPLS card connected to said control complex
• for mapping said MPLS class of service value and a drop precedence value of the ATM cell to an experimental field value for indicating a MPLS quality of service provisioning, for converting said ATM cell to a MPLS frame, and for
• incorporating said experimental field value into said MPLS frame for transmission through the MPLS network;
• wherein:
• said at least one ATM QoS parameter includes at least one of an ATM service category, a cell loss ration, and a cell delay variation;
• said experimental field value indicates drop precedence for said MPLS frame in addition to said MPLS class of service value;
• and,
• said MPLS class of service value is one of a number of MPLS class of service values, said drop precedence value is one of first and second drop precedence values, said experimental field value is one of a number of experimental field values, and each of said MPLS class of service values is assigned first and second experimental field values selected from said number of experimental field values, said first and second experimental field values being associated with said first and second drop precedence values, respectively.

A method for formatting a MPLS frame to support an ATM quality of service (QoS) parameter related to at least one ATM cell when said MPLS frame is transmitted on a MPLS communication network, said method comprising:

• mapping said ATM QoS parameter to a MPLS class of service value for a MPLS connection for said MPLS frame;
• mappig said MPLS class of service value and a drop precedence of said at least on ATM cell to an experimental field value for indicating a MPLS quality of service provisioning;
• inserting said experimental field value an experimenmai field of a header of said MPLS frame;
• and
• inserting contents of said ATM cell in said MPLS frame,
• wherein said experimental field value further indicates drop precedence for said MPLS frame, said drop precedence of said at least one ATM cell utilizes a value of drop precedence for each of said at least one ATM cell, and said ATM QoS parameter further includes at least one of an ATM service category, a cell loss ratio and a cell delay variation.

A method for routing at least one ATM cell through a MPLS network, said method comprising:

• mapping an ATM quality of service (QoS) parameter related to the at least one ATM cell to a MPLS class of service value for a MPLS connection for said MPLS network;
• mapping said MPLS class of service value and a drop procedence of said at least on ATM cell to an experimental field value for indicating a MPLS quality of service provisioning;
• creating a MPLS frame;
• inserting said experimental field value into an experimental field of a header of said MPLS frame;
• inserting contents of said at least one ATM cell in said MPLS frame;
• routing said MPLS frame through one or more routers in said MPLS network according to said experimental field value;
• wherein:
• said experimental field value further indicates drop precedence for said MPLS frame, said drop precedence of said at least one ATM cell utilizes a value of drop precedence for each of said at least one ATM cell, and said ATM QoS parameter further includes a at least one of an ATM service category, a cell loss ratio, and a cell delay variation;
• and,
• said experimental field value specifies experimental (EXP) inferred label switched path scheduling treatment and drop precedence treatment.

A method for transporting data traffic of a first transmission protocol through an MPLS network from an edge network element connected to an ingress point of the MPLS network to an egress point of the MPLS network, while maintaining a quality of service (QoS) of the data traffic, the method comprising:

• providing a first mapping table with correspondence between a plurality of QoS parameters relating to the data traffic arriving at the edge network element and a plurality of classes of service for MPLS frames generated from the data traffic at said edge network element for transmission through the MPLS network, each one of the plurality of classes of service for maintaining a QoS of its corresponding QoS parameter in the MPLS network;
• identifying a QoS parameter of a data element of the data traffic arriving at the edge device over a connection and encapsulating content from the data element into a MPLS frame;
• consulting the first mapping table to identify one class of the plurality of classes of service corresponding to the QoS parameter of the data element;
• consulting a second mapping table to identify a label field value associated with the one class of service and with a drop precedence value for the data element;
• inserting the label field value into an unused field of an outer label of the MPLS frame carrying the data element;
• and
• transporting the MPLS frame across the MPLS network, the MPLS frame identifying the one class of service and the drop precedence value for the data element to maintain the QoS of the data traffic.

A method for translating at least one quality of service (QoS) parameter related to a first cell-based transmission protocol from said first cell-based transmission protocol to a second transmission protocol for a data element being sent on a connection from a first cell-based commmunication network utilizing said first transmission protocol to a second communication network utilizing said second transmission protocol, said method comprising:

• mapping said at least one QoS parameter to a class of service value for said connection;
• mapping said class of service value and a drop precedence value of the data element to a label field value indicating a quality of service provisioning for said second transmission protocol;
• converting said data element of said connection to a second data element associated with said second transmission protocol;
• and,
• incorporating said label field value into said second data element for transmission of said second data element in the second network with the second transmission protocol;
• wherein said class of service value is one of a number of class of service values, said drop precedence value is one of first and second drop precedence values, said label field value is one of a number of label field values, and each of said class of service values is assigned first and second label field values selected from said number of label field values, said first and second label field values being associated with said first and second drop precedence values, respectively.