Query request service method for DNS (Domain Name System) recursive server

Abstract

The invention discloses a query request service method for a DNS (Domain Name System) recursive server, and belongs to the technical field of networks. The method comprises the following steps: 1) dividing cache of the DNS recursive server into a credible cache area and an incredible cache area; 2) looking up whether matched resources exist in a resource record of the credible cache area after the recursive server receives a query request; if yes, returning the matched resource record to a query terminal, and if not, sending a query request to an authorized server; 3) monitoring the responded data package arrival rate of the query request by the recursive server; 4) putting the responded data package of the query request in the incredible cache area by the recursive server if the responded data package arrival rate exceeds a credible threshold; sending a query request again to the authorized server if the responded data package arrival rate does not exceed the credible threshold, sending the obtained DNS resource record to the query terminal, and adding into the credible cache area. According to the invention, the possibility of caching poisoning is reduced, and the efficiency of query is ensured.

Description

technical field [0001] The invention relates to a query request service method of a DNS recursive server, belonging to the technical field of computer networks. Background technique [0002] The main entities of the Internet Domain Name System (Domain Name System, DNS) include recursive servers that provide resolution query services and authoritative servers that provide authoritative answer services. Its query process is as follows figure 1 shown. The specific steps are: [0003] 1) When the end user wishes to visit www.sina.com, send a DNS query request message to the recursive server; [0004] 2) If there is no relevant information about the domain name in the cache of the recursive server (assuming that there is neither the authoritative server address of com nor the authoritative server address of sina.com), the recursive server needs to initiate a query process to the root server to learn that com the address of the authoritative server; [0005] 3) The recursive ...

AI Technical Summary

Problems solved by technology

[0008] In the above query process, after the recursive server sends a query message to any authoritative server, if the corresponding forged response data packet can be received by the recursive server before the correct response data packet arrives, and matches the query data packet sent by the recursive server UDP port number and packet ID, the recursive server will cache the wrong authoritative resource records, resulting in cache poisoning

Images