Interworking functionality

IIIIIIH

US007480306B2

(12) United States Patent

Unbehagen et al.

(io) Patent No.: (45) Date of Patent:

US 7,480,306 B2 Jan. 20, 2009

(54) INTERWORKING FUNCTIONALITY

(75) Inventors: Paul Unbehagen, Cary, NC (US); Vasile Radoaca, Burlington, MA (US)

(73) Assignee: Nortel Networks Limited, St. Laurent, Quebec (CA)

( * ) Notice: Subject to any disclaimer, the term of this patent is extended or adjusted under 35 U.S.C. 154(b) by 706 days.

(21) Appl.No.: 10/742,653

(22) Filed: Dec. 19, 2003

(65) Prior Publication Data

US 2005/0165961 Al Jul. 28, 2005

(51) Int. CI.

H04L12/28 (2006.01)

(52) U.S. CI 370/401; 370/389; 370/469;

370/475

(58) Field of Classification Search 370/389 395.1,

370/401-405, 351, 409, 469, 475 See application file for complete search history.

(56) References Cited

U.S. PATENT DOCUMENTS

6,993,036 B2 * 1/2006 Mizuhara

370/401

7,113,512 Bl* 9/2006 Holmgren etal 370/395.53

7,400,647 Bl* 7/2008 Ciminoetal 370/466

2001/0009550 Al* 7/2001 Mizuhara 370/393

OTHER PUBLICATIONS

Shah, H. et al. "ARP Mediation for IP Interworking of Layer 2 VPN", PPVPN Working Group Internet Draft, (Versions 00 01 02) (Jun. 2003).

Shah, H. et al. "ARP Mediation for IP Interworking of Layer 2 VPN", PPVPN Working Group Internet Draft, pp. 1 -11, (Versions 00 01 02) (Jun. 2003).

* cited by examiner

Primary Examiner—Wing F. Chan
Assistant Examiner—Mark A. Mais

(7'4) Attorney, Agent, or Firm—Christopher & Weisberg, PA. (57) ABSTRACT

In one aspect a system and method for providing communication between Ethernet and frame relay routers includes generating a unique media access control (MAC) address for a frame relay router in communication with an Ethernet router, associating the MAC address with the frame relay router, and storing the MAC address in an interworking function device (IWF). The method also includes receiving at the IWF device an address resolution protocol (ARP) request from the Ethernet router and sending from the IWF device to the Ethernet router a response to the ARP request based on the stored MAC addresses.

14 Claims, 5 Drawing Sheets