Patent Document ID: 7529852
Application ID: 10848344

Base Claim:
1. A method for handling domain name system (DNS) pointer (PTR) packets, comprising: (a) receiving an IPv4 DNS PTR query that is being sent from an IPv4 device to an IPv6 DNS Server; (b) translating the IPv4 query into a first IPv6 query having an IP6.INT string, wherein an IP-ADDR.ARPA string in the IPv4 query is replaced with the IP6.INT string to form the first Ipv6 query having the IP6.INT string, and forwarding the translated first Ipv6 query having the IP6.INT string to the IPV6DNS Server; (c) translating the Ipv4 query into a second IPv6 query having an IP6.ARPA string, wherein the IP-ADDR.ARPA string in the IPv4 query is replaced with the IP6.ARPA string to form the second IPv6 query having the IP6.ARPA string, and forwarding the translated second Ipv6 query having the IP6.ARPA string to the IPv6 DNS Server; (d) generating an Ipv4 reply based on a valid reply or “no answer” reply from the IPv6 Server in response to either the second Ipv6 query having the IP6.ARPA string or the first Ipv6 query having the IP6.INT string, wherein the valid reply contains one or more answer records and the “no answer” reply does not contain one or more answer records; and (e) sending the generated IPv4 reply to the Ipv4 device.

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Claim 13:
13. The method as recited in claim 1 , wherein generating an IPv4 reply is performed based upon a “no-answer” reply from the IPv6 Server in response to either the second IPv6 query having the IP6.ARPA string or the first IPv6 query having the IP6.string if a valid reply has not been received in response to either the second IPv6 query having the IP6.ARPA string or the first IPv6 query having the IP6.INT string.