Address query response method, program, and apparatus, and address notification method, program, and apparatus

• US 20040143579A1
• Filed: 01/13/2004
• Published: 07/22/2004
• Est. Priority Date: 01/21/2003
• Status: Active Grant

• Current Assignee: Canon Kabushiki Kaisha (Canon Inc.)
• Original Assignee: Canon Kabushiki Kaisha (Canon Inc.)
• Inventors: Nakazawa, Hiroaki
• Granted Patent: US 7,415,536 B2
• Time in Patent Office: Days
• US Class Current: 707/10
• CPC Class Codes: H04L 61/4511 using domain name system [DNS]
• CPC Class Codes: H04L 61/4535 using an address exchange platform which sets up a session between two nodes, e.g. rendezvous servers, session initiation protocols [SIP] registrars or H.323 gatekeepers
• CPC Class Codes: H04L 61/4557 Directories for hybrid networks, e.g. including telephone numbers

Abstract

Upon reception of a query about the address of a server from a client, a DNS server sends a query about the address of that server to an external DNS server. The DNS server checks based on the address obtained from the external DNS server if connection to the server can be established. If connection to the server cannot be established, and the DNS server receives a query about the address of the server, the DNS server returns a response indicating that the address is not available. When the address is returned before the check process, the DNS sever sets an expiration time shorter than that of the address of the server obtained from the external DNS server as the expiration time of the address of the server.

Claims

1. A response method to a query about an address, comprising steps of:

receiving an address of a second apparatus from a first apparatus;

conducting a connection test with the second apparatus; and

returning. a message corresponding to the connection test result in the test step as a response to the query about the address of the second apparatus from the third apparatus.

2. The method according to claim 1, wherein the test step includes a step of conducting a connection test with the first apparatus using a protocol corresponding to the address of the second apparatus.

3. The method according to claim 1, wherein the reception step includes a step of receiving a first query about the address of the second apparatus, and receiving the address of the second apparatus from the first apparatus, and the returning step includes a step of receiving a second query about the address of the second apparatus, and returning the message corresponding to the connection test result in the test step to the third apparatus in response to the second.

4. The method according to claim 1, wherein the reception step comprises steps of:

storing the address of the second apparatus; and

inactivating the stored address of the second apparatus in accordance with an expiration time of the address of the second apparatus, the test step includes a step of repeating a connection test for the address of the second apparatus within the expiration time, and the returning step includes a step of returning the message corresponding to the latest connection test result in the test step.

5. A response program to a query about an address, comprising steps of:

receiving an address of a second apparatus from a first apparatus;

conducting a connection test with the second apparatus; and

returning a message corresponding to the connection test result in the test step in response to the query about the address of the second apparatus from the third.

6. The program according to claim 5, wherein the test step includes a step of conducting a connection test with the first apparatus using a protocol corresponding to the address of the second apparatus.

7. The program according to claim 5, wherein the reception step includes a step of receiving a first query about the address of the second apparatus, and receiving the address of the second apparatus from the first apparatus, and the returning step includes a step of receiving a second query about the address of the second apparatus, and returning the message corresponding to the connection test result in the test step to the third apparatus in response to the second.

8. The program according to claim 5, wherein the reception step comprises steps of:

storing the address of the second apparatus; and

inactivating the stored address of the second apparatus in accordance with an expiration time of the address of the second apparatus, the test step includes a step of repeating a connection test for the address of the second apparatus within the expiration time, and the returning step includes a step of returning the message corresponding to the latest connection test result in the test step.

9. A response apparatus, comprising:

connection unit which connects a network; and

generation unit which generates a response message to a query about an address of a second apparatus, the query is received from a third apparatus via the network connected to said connection unit, wherein said generation unit conducts a connection test with the second apparatus in accordance with the address of the second apparatus received from a first apparatus via the network connected to said connection unit, and generates the response message corresponding to the connection test result.

10. The apparatus according to claim 9, wherein said generation unit conducts a connection test with the first apparatus using a protocol corresponding to the address of the second apparatus.

11. The apparatus according to claim 9, wherein said generation unit receives the address of the second apparatus from the first apparatus in response to a first query about the address of the second apparatus received via the network connected to said connection unit, and generates the response message to a second query about the address of the second apparatus, which is received via the network connected to said connection unit, in correspondence with the connection test result.

12. The apparatus according to claim 9, wherein said generation unit comprises storage unit which stores the address of the second apparatus, inactivates the address of the second apparatus stored in said storage unit in accordance with an expiration time of the address of the second apparatus, repeats a connection test for the address of the second apparatus within the expiration time stored in said storage unit, and generates the response message in accordance with the latest connection test result.

13. An address notification method comprising the steps of:

sending a query about address of a second apparatus to a first apparatus in response to a query about the address of the second apparatus received from a third apparatus and

notifying, to the third apparatus, the address of the second apparatus and an expiration time of the address of the second apparatus which is shorter than an expiration time of the address of the second apparatus received from the first apparatus.

14. The method according to claim 13, wherein the notifying step includes a step of notifying, to the third apparatus, the expiration time prevents allow the third apparatus from re using the address of the second apparatus.

15. An address notification program comprising the steps of:

sending a query about address of a second apparatus to a first apparatus in response to a query about the address of the second apparatus received from a third apparatus and

notifying, to the third apparatus, the address of the second apparatus and an expiration time of the address of the second apparatus which is shorter than an expiration time of the address of the second apparatus received from the first apparatus.

16. The program according to claim 15, wherein the notifying step includes a step of notifying, to the third apparatus, the expiration time that prevents the third apparatus from re using the address of the second apparatus.

17. An address notification apparatus comprising:

connection unit which connects a network; and

notification unit which notifies an address of an second apparatus to a third apparatus via the network connected to said connection unit, wherein the notification unit sends a query about address of a second apparatus to a first apparatus in response to a query about the address of the second apparatus received from a third apparatus, and notifies, to the third apparatus, an expiration time of the address of the second apparatus which is shorter than an expiration time of the address of the second apparatus received from the first apparatus.

18. The apparatus according to claim 17, wherein the notification unit notifies, to the third apparatus, the expiration time that prevents the third apparatus from re using the address of the second apparatus.