Technique for multiprotocol transport using MPLS (multi-protocol label switching)

1. A router comprising:

a first port configured to receive a first frame having (i) a source media access control (MAC) address, (ii) a first network layer protocol identification immediately following said source MAC address and (iii) a network layer address following said network layer protocol identification;

a second port connectable to a Multi-Protocol Label Switching (MPLS) network; and

a circuit configured to (i) insert a first MPLS label into said first frame while retaining said first network layer protocol identification, (ii) present said first frame in said MPLS network, (iii) receive a second frame having a second MPLS label and a second network layer protocol identification, and (iv) present said second frame external to said MPLS network per said second network layer protocol received in said second frame.

2. The router according to claim 1 , wherein said circuit is further configured to:

receive a second frame having a second network layer protocol identification having a difference value than said first network layer protocol identification;

insert a second MPLS label into said second frame while retaining said second network layer protocol identification; and

forward said second frame in said MPLS network.

3. The router according to claim 2 , wherein said circuit is further configured to:

transmit said first frame along a path in said MPLS network; and

transmit said second frame along said path.

4. The router according to claim 1 , wherein said circuit is further configured to:

transmit a plurality of frames having a plurality of different protocol through a single traffic-engineered path in said MPLS network.

5. The router according to claim 4 , wherein said transmission through said traffic-engineered path is bidirectional.

6. The router according to claim 1 , wherein the circuit is further configured to:

create an MPLS label stack field between a data link layer address field and a network layer protocol identification field in said first frame; and

insert said first MPLS label into said MPLS label stack field.

7. The router according to claim 1 , wherein said first frame comprises a Point-to-Point Protocol frame.

8. A method of operation in a Multi-Protocol Label Switching (MPLS) network comprising the steps of:

(A) receiving a first frame having (i) a source media access control (MAC) address, (ii) a first network layer protocol identification immediately following said source MAC address and (iii) a network layer address following said first network layer protocol identification;

(B) inserting a first MPLS label into said first frame while retaining said first network layer protocol identification;

(C) presenting said first frame in said MPLS network;

(D) receiving a second frame having a second network layer protocol identification different than said first network layer protocol identification;

(E) inserting a second MPLS label into said second frame while retaining said second network layer protocol identification; and

(F) forwarding said second frame in said MPLS network.

9. The method according to claim 8 , further comprising the steps of:

transmitting said first frame along a path in said MPLS network; and

transmitting said second frame along said path.

10. The method according to claim 8 , further comprising the steps of:

receiving a second frame having a second MPLS label and a second network layer protocol identification; and

presenting said second frame external to said MPLS network per said second network layer protocol identification received in said second frame.

11. The method according to claim 8 , further comprising the step of:

transmitting a plurality of frames having a plurality of different protocol through a single traffic-engineered path in said MPLS network.

12. The method according to claim 11 , wherein transmitting through said traffic-engineered path is bidirectional.

13. The method according to claim 8 , wherein step (B) comprises the sub-steps of:

creating an MPLS label stack field between a data link layer address field and a network layer protocol identification field in said first frame; and

inserting said first MPLS label into said MPLS label stack field.

14. The method according to claim 8 , wherein said MPLS network is defined by a Request For Comment 3031 provided by an Internet Engineering Task Force.

15. The method according to claim 8 , wherein said steps (A) through (C) are stored in a storage medium as a software program that is readable and executable by a router to insert said first frame into said MPLS network.

16. The method according to claim 8 , wherein said first network protocol identifier indicates a network layer protocol of data encapsulated by said first frame.

17. The method according to claim 8 , wherein said first frame and second frame and are both transferred in a same label switched path in said MPLS network.

18. A router comprising:

means for receiving a first frame having (i) a source media access control (MAC) address, (ii) a first network layer protocol identification immediately following said source MAC address and (iii) a network layer address following said first network layer protocol identification;

means for inserting a first Multi-Protocol Label Switching (MPLS) label into said first frame while retaining said first network layer protocol identification;

means for forwarding said frame in an MPLS network;

means for receiving a second frame having a second network layer protocol identification different than said first network layer protocol identification;

means for inserting a second MPLS label into said second frame while retaining said second network layer protocol identification; and

means for forwarding said second frame in said MPLS network.