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:
Aug. 10, 2004
Filed:
May. 27, 1998
Nurettin B. Beser, Evanston, IL (US);
3Com Corporation, Marlborough, MA (US);
Abstract
A method and system is provided to send and receive Dynamic Host Configuration Protocol (“DHCP”) messages in a data-over-cable system via a route with one or more routers. The routers may apply one or more different protocol filters to DHCP messages, such as filtering out DHCP messages with a “Martian” Internet Protocol (“IP”) address (e.g., 0.0.0.0) and other characteristics. The Martian IP address is commonly used as an initial IP address in a DHCP initialization sequence but is often filtered out by routers as an invalid IP address. DHCP messages are received by a first protocol agent from a first User Datagram Protocol (“UDP”) port. The first UDP port is used by DHCP servers and network devices such as cable modems and customer premise equipment to send and receive DHCP messages via a route that may apply one or more DCHP filters. The first protocol agent sends the DHCP messages to a second protocol agent on a second UDP port via a route that does not apply filters to the DHCP messages. The first protocol agent receives DHCP messages from the second protocol agent on the second UDP port. The first protocol agent sends messages back to a DHCP protocol server or network device such as a cable modem on the first UDP port. The protocol agent allows DHCP messaging to be seamlessly used in a data-over-cable system with routers that apply a variety of protocol filters to DHCP messages.