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US5922049A Expired / Lapsed US ⏱️ 0.0 years remaining

Method for using DHCP and marking to override learned IP addesseses in a network

Assignee: Oracle America Inc
•
Filing: 1996-12-09
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Granted: 1999-07-13
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Expires: 2016-12-09
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Abstract

Abstract A preferred embodiment of the present invention includes a method and apparatus for routing an IP packets in a network of client systems. The router forwards IP packets between the client systems and the server systems. More specifically, the router can be pre-configured to include one or more "routes." Each route is a mapping between an IP address and a client system. The router may also learn route from other routers and by analysis of IP packets. Preferably, the routes known by the router are included in a route table. The router also monitors DHCP assignment of IP addresses to client systems within the network. When the DHCP assignment of an IP address is detected, the router creates a new route that associates the newly assigned IP address and the corresponding client system. The new route is marked so that it may only be overwritten by a subsequent DHCP assignment. The router then updates the route table to include the new route and purges the route table of learned routes that have been invalidated by the new route. In this way, the present invention allows dynamically assigned IP addresses to override learned routes.

Inventors

  • 👤 Sanjay R. Radia
  • 👤 Thomas K. Wong
  • 👤 Swee B. Lim
  • 👤 Panagiotis Tsirigotis
  • 👤 Robert J. Goedman
  • 👤 Michael W. Patrick

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-11-02 14:10
CPC Classifications
H; H04; H04L; H04L45/00; H04L61/00; H04L61/50; H04L61/5007; H04L61/5014; H04L61/5046; H04L61/5076

Claims Analysis

Total Claims: 21
Claim 1
Independent Claim 123 words
A method for routing packets in a computer network that includes one or more client systems connected to a router, the router including one or more routes, each route mapping an IP address to a client system, the method comprising the steps, performed by the router, of: detecting the allocation of a specified IP address to a specified client system; creating a new route within the router, the new route mapping the specified IP address to the specified client system; marking the new route so that it can only be overwritten by a subsequent DHCP address assignment; deleting routes stored within the router that are invalidated by the new route; and routing IP packets in accordance with the routes stored within the router.
Claim 2
Independent Claim 123 words
A method for routing packets in a computer network that includes one or more client systems connected to a router, the router including one or more routes, each route mapping an IP address to a client system, the method comprising the steps, performed by the router, of: detecting the allocation of a specified IP address to a specified client system; creating a new route within the router, the new route mapping the specified IP address to the specified client system; marking the new route so that it can only be overwritten by a subsequent DHCP address assignment; deleting routes stored within the router that are invalidated by the new route; and routing IP packets in accordance with the routes stored within the router.
Claim 3
Dependent Claim 61 words
A method as recited in claim 1 wherein the network includes a DHCP server and the step of detecting the allocation of a specified IP address to a specified client system further comprising the step, performed by the router, of detecting a DHCPACK sent by the DHCP server, the DHCPACK including the specified IP address allocated to the specified client system.
Claim 4
Dependent Claim 51 words
A method as recited in claim 1 wherein the step of deleting routes stored within the router that are invalidated by the new route further comprises the step, performed by the router, of deleting routes that associate the specified client system with IP addresses that are not the specified IP address.
Claim 5
Dependent Claim 51 words
A method as recited in claim 1 wherein the step of deleting routes stored within the router that are invalidated by the new route further comprises the step, performed by the router, of deleting routes that associate the specified IP address with clients systems that are not the specified client system.
Claim 6
Dependent Claim 25 words
A method as recited in claim 1 wherein one or more of the routes stored within the router are established during configuration of the router.
Claim 7
Dependent Claim 37 words
A method as recited in claim 5 wherein the routes established during configuration of the router are not changed by the steps of creating a new route within the router and deleting routes stored within the router.
Claim 8
Dependent Claim 183 words
A computer program product comprising: a computer usable medium having computer readable code embodied therein for routing packets in a computer network that includes one or more client systems connected to a router, the router including one or more routes, each route mapping an IP address to a client system, the computer program product including: first computer readable program code devices configured to cause a computer system to detect the allocation of a specified IP address to a specified client system; second computer readable program code devices configured to cause the computer system to create a new route within the router, marking the new route so that it can only be overwritten by a subsequent DHCP address assignment the new route mapping the specified IP address to the specified client system; third computer readable program code devices configured to cause the computer system to delete routes stored within the router that are invalidated by the new route; and fourth computer readable program code devices configured to cause the computer system to route IP packets in accordance with the routes stored within the router.
Claim 9
Dependent Claim 183 words
A computer program product comprising: a computer usable medium having computer readable code embodied therein for routing packets in a computer network that includes one or more client systems connected to a router, the router including one or more routes, each route mapping an IP address to a client system, the computer program product including: first computer readable program code devices configured to cause a computer system to detect the allocation of a specified IP address to a specified client system; second computer readable program code devices configured to cause the computer system to create a new route within the router, marking the new route so that it can only be overwritten by a subsequent DHCP address assignment the new route mapping the specified IP address to the specified client system; third computer readable program code devices configured to cause the computer system to delete routes stored within the router that are invalidated by the new route; and fourth computer readable program code devices configured to cause the computer system to route IP packets in accordance with the routes stored within the router.
Claim 10
Dependent Claim 60 words
A computer program product as recited in claim 7 wherein the first computer readable program code devices further comprises fifth computer readable program code devices configured to cause the computer system to detect a DHCPACK message sent by a DHCP server to the specified client system, the DHCPACK message including the specified IP address allocated to the specified client system.
Claim 11
Dependent Claim 47 words
A computer program product as recited in claim 8 wherein the third computer readable program code devices are configured to cause the computer system to delete routes stored within the router that associate the specified client system with IP addresses that are not the specified IP address.
Claim 12
Dependent Claim 47 words
A computer program product as recited in claim 8 wherein the third computer readable program code devices are configured to cause the computer system to delete routes stored within the router that associate the specified IP address with clients systems that are not the specified client system.
Claim 13
Dependent Claim 27 words
A computer program product as recited in claim 8 wherein one or more of the routes stored within the router are established during configuration of the router.
Claim 14
Dependent Claim 36 words
A computer program product as recited in claim 11 wherein the routes established during configuration of the router are not changed by the second computer readable program code devices and third computer readable program code devices.
Claim 15
Independent Claim 156 words
An apparatus for routing packets in a computer network that includes one or more client systems connected to a router, the router including one or more routes, each route mapping an IP address to a client system, the apparatus comprising: a first portion configured to cause a computer system to detect the allocation of a specified IP address to a specified client system; a second portion configured to cause the computer system to create a new route within the router, marking the new route so that it can only be overwritten by a subsequent DHCP address assignment the new route mapping the specified IP address to the specified client system; a third portion configured to cause the computer system to delete routes stored within the router that are invalidated by the new route; and a fourth portion configured to cause the computer system to route IP packets in accordance with the routes stored within the router.
Claim 16
Independent Claim 156 words
An apparatus for routing packets in a computer network that includes one or more client systems connected to a router, the router including one or more routes, each route mapping an IP address to a client system, the apparatus comprising: a first portion configured to cause a computer system to detect the allocation of a specified IP address to a specified client system; a second portion configured to cause the computer system to create a new route within the router, marking the new route so that it can only be overwritten by a subsequent DHCP address assignment the new route mapping the specified IP address to the specified client system; a third portion configured to cause the computer system to delete routes stored within the router that are invalidated by the new route; and a fourth portion configured to cause the computer system to route IP packets in accordance with the routes stored within the router.
Claim 17
Dependent Claim 51 words
An apparatus as recited in claim 13 wherein the first portion further comprises a fifth portion configured to cause the computer system to detect a DHCPACK message sent by a DHCP server to the specified client system, the DHCPACK message including the specified IP address allocated to the specified client system.
Claim 18
Dependent Claim 43 words
An apparatus as recited as recited in claim 14 wherein the third portion is configured to cause the computer system to delete routes stored within the router that associate the specified client system with IP addresses that are not the specified IP address.
Claim 19
Dependent Claim 43 words
An apparatus as recited as recited in claim 14 wherein the third portion is configured to cause the computer system to delete routes stored within the router that associate the specified IP address with clients systems that are not the specified client system.
Claim 20
Dependent Claim 27 words
An apparatus as recited as recited in claim 13 wherein one or more of the routes stored within the router are established during configuration of the router.
Claim 21
Dependent Claim 28 words
An apparatus as recited as recited in claim 17 wherein the routes established during configuration of the router are not changed by the second portion and third portion.

References Cited (Backward Citations)

EP0483547A1 Cited
US5473599A Cited
US5835723A Cited
US5790548A Cited
US5754790A Cited
US5805594A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 2002-07-12 2003-01-11 2003-07-13 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 2006-07-12 2007-01-11 2007-07-13 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 2010-07-12 2011-01-11 2011-07-13 $7700.00 Window Closed / Lapsed

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