The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Dec. 13, 2005
Filed:
Nov. 16, 2000
Lewis T. Donzis, San Antonio, TX (US);
Earnest E. Hughes, San Antonio, TX (US);
Ryan M. Matelske, San Antonio, TX (US);
Peter W. Baron, San Antonio, TX (US);
Lewis T. Donzis, San Antonio, TX (US);
Earnest E. Hughes, San Antonio, TX (US);
Ryan M. Matelske, San Antonio, TX (US);
Peter W. Baron, San Antonio, TX (US);
Nortel Networks Limited, St. Laurent, CA;
Abstract
A communication system includes a data network that is coupled to various nodes, including routers. In one example arrangement, a first router is part of a first local network and a second router is part of a second local network. Each router includes a security gateway module and a keep-alive module. The security gateway module is capable of establishing a secure link, such as one according to an Internet Protocol Security (IPsec) protocol, over the data network. The keep-alive module sends one or more ping messages over the secure link to the remote router (or a node coupled to the router), which responds with appropriate ping replies to indicate that a link is alive.