SEAMLESS SWITCH OVER FROM CENTRALIZED TO DECENTRALIZED MEDIA STREAMING

• US 20100189097A1
• Filed: 04/30/2009
• Published: 07/29/2010
• Est. Priority Date: 01/29/2009
• Status: Active Grant

• Current Assignee: Avaya LLC (Avaya Incorporated), Avaya Management L.P. (Avaya Incorporated)
• Original Assignee: Avaya Incorporated
• Inventors: Brinkmann, Werner, Weissmann, Marc, Nitsch, Guido
• Granted Patent: US 9,525,710 B2
• Time in Patent Office: Days
• US Class Current: 370/352
• CPC Class Codes: H04L 65/103 in the network
• CPC Class Codes: H04L 65/1069 Session establishment or de-establishment
• CPC Class Codes: H04L 65/1083 In-session procedures
• CPC Class Codes: H04L 65/80 Responding to QoS

Abstract

A media gateway is provided that enables seamless switchover between a centralized media stream passing between first and second endpoints and through the media gateway and a decentralized media stream passing between the first and second endpoints, but bypassing the media gateway. The gateway provides synchronization information to the first and second endpoints to enable synchronization of the centralized and decentralized media streams. After synchronization is completed, the centralized media stream is disconnected in favor of the decentralized media stream.

Claims

1. A method comprising:

(a) setting up, by a media gateway, a centralized media stream passing between a first and a second endpoint and through the media gateway;

(b) setting up a decentralized media stream passing between the first and second endpoints, but bypassing the media gateway, the centralized and decentralized media streams being temporally overlapping;

(c) synchronizing, by at least one of the first and second endpoints, the centralized and decentralized media streams; and

(d) in response to step (c), disconnecting, by the at least one of the first and second endpoints, the centralized media stream while continuing the decentralized media stream.

2. The method of claim 1, wherein the centralized media stream is set up before the decentralized media stream and disconnected before the decentralized media stream is disconnected, and wherein the synchronizing step is performed before the decentralized media stream is set up.

3. The method of claim 1, wherein the synchronizing step comprises the sub-steps:

(C1) calculating, by the media gateway, a first difference between a first segment of the centralized media stream incoming to the media gateway from the first endpoint and a second segment of the centralized media stream outgoing from the media gateway to the second endpoint;

(C2) calculating, by the media gateway, a second difference between a third segment of the centralized media stream incoming to the media gateway from the second endpoint and a fourth segment of the centralized media stream outgoing from the media gateway to the first endpoint;

(C2) sending to the second endpoint the first difference and a first electronic identifier associated with the first endpoint; and

(C3) sending to the first endpoint the second difference and a second electronic identifier associated with the second endpoint.

4. The method of claim 3, wherein the first and second electronic identifiers are synchronization source identifiers and wherein the first and second differences are each a difference between an incoming timestamp for an incoming packet having a first payload and an outgoing timestamp for an outgoing packet having the first payload.

5. The method of claim 3, wherein the first and second electronic identifiers are synchronization source identifiers and wherein the first and second differences are each a difference between a packet sequence number for an incoming packet having a first payload and a packet sequence number of an outgoing packet having the first payload.

6. The method of claim 1, wherein the centralized media stream is disconnected upon the occurrence of at least one of transmission and/or receipt by the media gateway of a predetermined number of packets, passage of a predetermined time, and receipt, by the media gateway, of a signal from an endpoint, the signal requesting disconnection of the centralized media stream.

7. The method of claim 1, wherein step (b) comprises the sub-steps:

(B1) determining that the first, second, third and fourth media stream segments define a Voice over Internet Protocol session between the first and second endpoints;

(B2) determining that both the first and second media stream segments use at least one of a common and negotiable codec;

(B3) determining that the third and fourth media stream segments use at least one of a common and negotiable codec;

(B4) determining that the first and second media stream segments use at least one of a common and negotiable frame size;

(B5) determining that the third and fourth media stream segments use at least one of a common and negotiable frame size; and

(B6) harmonizing encryption parameters between the first and second media stream segments; and

(B7) harmonizing encryption parameters between the third and fourth media stream segments.

8. The method of claim 1, wherein step (d) comprises the sub-steps:

(D1) identifying, by the first endpoint, a packet in a first buffer of the endpoint, the packet being from the centralized media stream;

(D2) calculating, by the first endpoint, a corresponding packet in the decentralized stream;

(D3) locating the corresponding packet in a second buffer, the second buffer being associated with the decentralized media stream; and

(D4) in response to sub-step (D3), determining that the centralized media stream may be disconnected.

9. A computer readable medium comprising processor-executable instructions to perform the steps of claim 1.

10. A media gateway, comprising:

a processor operable to;

set up a centralized media stream passing between a first and a second endpoint and through the media gateway;

set up a decentralized media stream passing between the first and second endpoints, but bypassing the media gateway, the centralized and decentralized media streams being temporally overlapping;

provide synchronization information to at least one of the first and second endpoints to enable synchronization by the at least one of the first and second endpoints of the centralized and decentralized media streams; and

after synchronization is completed, disconnect the centralized media stream in favor of the decentralized media stream.

11. The media gateway of claim 10, wherein the centralized media stream is set up before the decentralized media stream and disconnected before the decentralized media stream is disconnected, and wherein the synchronization operation is performed after the decentralized media stream is set up.

12. The media gateway of claim 10, wherein the synchronizing operation comprises the sub-operations:

calculate a first difference between a first segment of the centralized media stream incoming to the media gateway from the first endpoint and a second segment of the centralized media stream outgoing from the media gateway to the second endpoint;

calculate a second difference between a third segment of the centralized media stream incoming to the media gateway from the second endpoint and a fourth segment of the centralized media stream outgoing from the media gateway to the first endpoint;

send to the second endpoint the first difference and a first electronic identifier associated with the first endpoint; and

send to the first endpoint the second difference and a second electronic identifier associated with the second endpoint.

13. The media gateway of claim 12, wherein the first and second electronic identifiers are synchronization source identifiers and wherein the first and second differences are each a difference between a timestamp for an incoming packet having a first payload and a timestamp for an outgoing packet having the first payload.

14. The media gateway of claim 12, wherein the first and second electronic identifiers are synchronization source identifiers and wherein the first and second differences are each a difference between a sequence number of an incoming packet having a first payload and a sequence number of an outgoing packet having the first payload.

15. The media gateway of claim 10, wherein the centralized media stream is disconnected upon the occurrence of at least one of transmission and/or receipt by the media gateway of a predetermined number of packets, passage of a predetermined time, and receipt, by the media gateway, of a signal from an endpoint, the signal requesting disconnection of the centralized media stream.

16. The media gateway of claim 12, wherein the operation of setting up the decentralized media stream comprises the sub-operations:

determine that the first, second, third and fourth media stream segments define a Voice over Internet Protocol session between the first and second endpoints;

determine that both the first and second media stream segments use at least one of a common and negotiable codec;

determine that the third and fourth media stream segments use at least one of a common and negotiable codec;

determine that the first and second media stream segments use at least one of a common and negotiable frame size;

determine that the third and fourth media stream segments use at least one of a common and negotiable frame size; and

harmonize encryption parameters between the first and second media stream segments; and

harmonize encryption parameters between the third and fourth media stream segments.

17. The media gateway of claim 10, wherein the disconnect operation comprises the sub-operations:

identify, by the first endpoint, a packet in a first buffer of the first endpoint, the packet being from the centralized media stream;

calculate, by the first endpoint, a corresponding packet in the decentralized stream;

locate the corresponding packet in a second buffer of the first endpoint, the second buffer being associated with the decentralized media stream; and

in response to locating the corresponding packet in the second buffer, determining that the centralized media stream may be disconnected.

18. An endpoint, comprising:

a network communication interface in communication with a centralized media stream passing through a media gateway and terminating at a remote endpoint and a decentralized media steam terminating at the remote endpoint and bypassing the media gateway, the centralized and decentralized media streams being simultaneously active;

a call control operable to receive synchronization information from the media gateway and synchronize the centralized and decentralized media streams to enable switch over from the centralized media stream to the decentralized media stream.

19. The endpoint of claim 18, wherein the centralized media stream is set up before the decentralized media stream and disconnected before the decentralized media stream is disconnected, and wherein the synchronization information comprises a synchronization source identifier associated with the remote endpoint and a difference between a timestamp of an incoming packet having a first payload and a packet timestamp of an outgoing packet having the first payload.

20. The endpoint of claim 18, wherein the synchronization information comprises a synchronization source identifier associated with the remote endpoint and a difference between a sequence number of an incoming packet having a first payload and a sequence number of an outgoing packet having the first payload.