Controlling registration floods in VoIP networks via DNS

• US 20110090900A1
• Filed: 10/20/2009
• Published: 04/21/2011
• Est. Priority Date: 10/20/2009
• Status: Active Grant

• Current Assignee: AT&T Intellectual Property I LP (AT&T, Inc.)
• Original Assignee: AT&T Intellectual Property I LP (AT&T, Inc.)
• Inventors: Yasrebi, Mehrad, Qiu, Chaoxin, Jackson, James E.
• Granted Patent: US 8,355,395 B2
• Time in Patent Office: Days
• US Class Current: 370/352
• CPC Class Codes: H04L 12/66 Arrangements for connecting between networks having differing types of switching systems, e.g. gateways
• CPC Class Codes: H04L 41/50 Network service management, e.g. ensuring proper service fulfilment according to agreements
• CPC Class Codes: H04L 47/286 Time to live
• CPC Class Codes: H04L 47/765 triggered by the end-points
• CPC Class Codes: H04L 61/4511 using domain name system [DNS]
• CPC Class Codes: H04L 61/5007 Internet protocol [IP] addresses
• CPC Class Codes: H04L 65/1016 IP multimedia subsystem [IMS]
• CPC Class Codes: H04L 65/1073 Registration or de-registration
• CPC Class Codes: H04L 65/1104 Session initiation protocol [SIP]
• CPC Class Codes: H04L 67/1036 Load balancing of requests to servers for services different from user content provisioning, e.g. load balancing across domain name servers
• CPC Class Codes: H04M 7/006 Networks other than PSTN/ISDN providing telephone service, e.g. Voice over Internet Protocol (VoIP) , including next generation networks with a packet-switched transport layer H04L65/00 takes precedence; aspects not specific to the type of network H04M3/00; special services in those networks H04M3/42

Abstract

A mechanism controls global synchronization, or registration floods, that may result when a large number of endpoints in a Voice over Internet Protocol (VoIP) network such as an Internet Protocol Multimedia Subsystem (IMS) come online simultaneously after a catastrophic failure. The mechanism allows the Domain Name System (DNS) infrastructure to efficiently control the overload condition by registering user end points with backup border elements, and by staggering and by randomizing the time-to-live (TTL) parameter in registrations with backup border elements.

Claims

1. A method for registering a multimedia endpoint via a border element in a multimedia network, the method comprising the steps of:

at a DNS server in the multimedia network, receiving a DNS query from the multimedia endpoint, the query containing an identifier of the end point and requesting an address of a border element for use in registering for a multimedia service;

based on the identifier of the end point, determining a primary border element associated with the end point;

if a volume of DNS queries from end points associated with the primary border element is below a threshold capacity of the primary border element, then responding to the DNS query with an identification of the primary border element for use by the endpoint in registering for the multimedia service;

if the volume of DNS queries is above the threshold capacity of the primary border element, then;

determining a backup border element associated with the end point; and

if a volume of DNS queries from endpoints associated with the backup border element is below a threshold capacity of the backup border element, then responding to the DNS query with an identification of the backup border element for use by the endpoint in registering for the multimedia service;

if the volume of DNS queries of the primary border element is above a threshold capacity of the primary border element and if a volume of DNS queries of the backup border element is above a threshold capacity of the backup border element, then;

responding to the DNS query with a message forcing the endpoint to transmit another DNS query at a later time.

2. The method of claim 1, wherein the step of responding to the DNS query with an identification of the backup border element for use by the endpoint in registering for the multimedia service further comprises randomizing a time-to-live (TTL) parameter in the DNS query response to allow reverting of end points to primary border elements in a controlled manner.

3. The method of claim 1, wherein the DNS server utilizes a standard DNS protocol in receiving and responding to DNS queries.

4. The method of claim 1, wherein the border elements are session border controllers.

5. The method of claim 1, wherein the multimedia service is a voice-over IP (VoIP) service.

6. The method of claim 1, wherein the backup border element is a primary border element associated with a second endpoint.

7. The method of claim 1, wherein the identifier of the endpoint is an IP address.

8. The method of claim 1, wherein the address of the border element is a fully qualified domain name (FQDN).

9. The method of claim 1, wherein, if the volume of DNS queries is below a threshold capacity of the primary border element, then the method further comprises the steps of:

receiving at the primary border element a registration request from the end point; and

transmitting from the primary border element to a network registrar a registration request on behalf of the endpoint.

10. The method of claim 1, wherein:

the step of determining a primary border element associated with the end point further comprises determining a plurality of primary border elements associated with the end point, and

the step of responding to the DNS query with an identification of a primary border element for use by the endpoint in registering for the multimedia service is performed if the volume of DNS queries of any one of the associated primary border elements is below a threshold capacity of that primary border element.

11. A computer-usable medium having computer readable instructions stored thereon for execution by a processor to perform a method for registering a multimedia endpoint via a border element in a multimedia network, the method comprising the steps of:

at a DNS server in the multimedia network, receiving a DNS query from the multimedia endpoint, the query containing an identifier of the end point and requesting an address of a border element for use in registering for a multimedia service;

based on the identifier of the end point, determining a primary border element associated with the end point;

if a volume of DNS queries from end points associated with the primary border element is below a threshold capacity of the primary border element, then responding to the DNS query with an identification of the primary border element for use by the endpoint in registering for the multimedia service;

if the volume of DNS queries is above a threshold capacity of the primary border element, then;

determining a backup border element associated with the end point; and

if a volume of DNS queries from end points associated with the backup border element is below a threshold capacity of the backup border element, then responding to the DNS query with an identification of the backup border element for use by the endpoint in registering for the multimedia service;

if the volume of DNS queries of the primary border element is above a threshold capacity of the primary border element and if a volume of DNS queries of the backup border element is above a threshold capacity of the backup border element, then;

responding to the DNS query with a message forcing the endpoint to transmit another DNS query at a later time.

12. The computer-usable medium of claim 11, wherein the step of responding to the DNS query with an identification of the backup border element for use by the endpoint in registering for the multimedia service further comprises randomizing a time-to-live (TTL) parameter in the DNS query response to allow reverting of end points to primary border elements in a controlled manner.

13. The computer-usable medium of claim 11, wherein the DNS server utilizes a standard DNS protocol in receiving and responding to DNS queries.

14. The computer-usable medium of claim 11, wherein the border elements are session border controllers.

15. The computer-usable medium of claim 11, wherein the multimedia service is a voice-over IP (VoIP) service.

16. The computer-usable medium of claim 11, wherein the backup border element is a primary border element associated with a second endpoint.

17. The computer-usable medium of claim 11, wherein the identifier of the endpoint is an IP address.

18. The computer-usable medium of claim 11, wherein the address of the border element is a fully qualified domain name (FQDN).

19. The computer-usable medium of claim 11, wherein, if the volume of DNS queries is below a threshold capacity of the primary border element, then the method further comprises the steps of:

receiving at the primary border element a registration request from the end point; and

transmitting from the primary border element to a network registrar a registration request on behalf of the endpoint.

20. The computer-usable medium of claim 11, wherein:

the step of determining a primary border element associated with the end point further comprises determining a plurality of primary border elements associated with the end point, and

the step of responding to the DNS query with an identification of a primary border element for use by the endpoint in registering for the multimedia service is performed if the volume of DNS queries of any one of the associated primary border elements is below a threshold capacity of that primary border element.