Method and apparatus for operating domain name servers

• US 6,351,743 B1
• Filed: 05/26/1999
• Issued: 02/26/2002
• Est. Priority Date: 05/26/1999
• Status: Expired due to Term

• Current Assignee: WSOU Investments, LLC (WSOU Holdings, LLC)
• Original Assignee: Lucent Technologies, Inc. (Nokia Corporation)
• Inventors: Totapally, Mahesh Kumar, Spencer, Gordon Thomas, Larson, Timothy John, DeArdo, Carmen Edward
• Primary Examiner(s): Choules, Jack
• Assistant Examiner(s): LEWIS, CHERYL RENEA
• Application Number:
  US09/318,908
• Time in Patent Office: 1,007 Days
• Field of Search: 707/10, 707/3, 707/5, 707/200, 709/203, 709/219, 711/118, 711/117
• US Class Current: 707/718
• CPC Class Codes: G06F 16/9574 of access to content, e.g. by caching
• CPC Class Codes: H04L 61/4511 using domain name system [DNS]
• CPC Class Codes: H04L 61/58 Caching of addresses or names
• CPC Class Codes: H04L 67/1001 for accessing one among a plurality of replicated servers
• CPC Class Codes: H04L 67/10015 Access to distributed or replicated servers, e.g. using brokers
• CPC Class Codes: H04L 67/1008 based on parameters of servers, e.g. available memory or workload monitoring of computer activity G06F11/30
• CPC Class Codes: Y10S 707/99933 Query processing, i.e. searching
• CPC Class Codes: Y10S 707/99935 Query augmenting and refining, e.g. inexact access

Abstract

A domain name server, DNS, for Internet Protocol or Intranet Protocol networks, that has a non-cached domain name server connected to a cached domain name server, and a query server that is connected to both the non-cached DNS and the cached DNS. The query server balances the query load between the DNSs. The query server compares counts of outstanding queries of each DNS and assigns the next query to the DNS with the fewer outstanding counts, unless the query is a special type known as an authoratative query. All authoratative queries are processed by the non-cached DNS. This is because the DNS information stored in the non-cached server is more carefully updated so its information has a higher level of correctness than the information in the cached DNS. Periodic updating of the non-cached DNS keeps its information at this higher level of correctness. The cached DNS runs a little faster because its domain name information updating is simpler than the non-cached DNS, but the chances for a DNS error or stale node address are higher.

Claims

1. A method for operating a DNS having a named server and a cached server, said method comprising the steps of:

a. receiving a query;

b. determining if the received query is authoratative, if it is authoratative, jumping to step h;

c. determining if the outstanding named query count is greater than the outstanding cached query count, if the outstanding named query count is not greater, jumping to step h;

d. sending the non-authoratative query to a cached server process;

e. incrementing a cached query received count;

f. processing the query;

g. incrementing a cached queries processed count and returning to step a. to receive the next query;

h. sending the non-authoratative query to named server process;

i. incrementing a named query received count;

j. processing the query; and

k. incrementing a named queries processed count and returning to step a. to receiving the next query.

2. The method of claim 1, wherein the non-authoratative queries are processed in pipeline fashion where a query does not have to have completed processing before a subsequent query can be received and processed to completion.

3. A domain name server, DNS, comprising:

a named domain name server;

a cached domain name server;

a memory connected to and shared by said named domain name server and said cached domain name server for storing data of outstanding queries for said name servers;

a query server connected to said named domain name server, said cached domain name server and said memory that distributes incoming domain name server queries among said domain name servers according to said data of outstanding queries in said memory.

4. The DNS according to claim 3, wherein said query server directs authoritative queries to said named server.

5. The DNS according to claim 4, wherein said query server distributes non-authoritative queries between said named domain name server and said cached domain name server.

6. The DNS according to claim 4, wherein said query server distributes non-authoritative queries between said named domain name server and said cached domain name server by sending each non-authoritative query to the domain name server having a lesser number of outstanding queries.

7. A domain name server, DNS, comprising:

a named domain name server;

a cached domain name server; and

a query server connected to said named domain name server queries and said cached domain name server that distributes incoming domain name server queries among said domain name servers;

wherein said query server directs authoritative queries to said named domain name server; and

wherein said query server distributes non-authoritative queries between said named domain name server and said cached domain name server by sending each non-authoritative query to the domain name server having a lesser number of outstanding queries.