In-band DPI media reservation modifications to RFC 3313
In various exemplary embodiments, a Deep Packet Inspection device is integrated into a provider edge router associated with a user agent client or provided externally. The DPI device monitors the exchange of packets between an originating proxy and a user agent client and inspects the packets to identify SIP control messages. By monitoring the messages exchanged between the two devices, the DPI device may determine the type of application, desired QoS, source, destination, and other information related to the connection. Using this information, the router may then access a policy database to determine whether there is a QoS policy for the application and/or user. Based on this determination, the router may initiate network reservation for an anticipated data flow or store the information so the flow of packets can be remarked as the packets arrive. Accordingly, in various exemplary embodiments, the edge router is aware that QoS should be granted.
1. A system for implementing Quality of Service (QoS) for a Session Initiation Protocol (SIP) connection between a source node and a destination node, the system comprising:
a receiver that receives data transferred between the source node and the destination node;
a transmitter that transmits data between the source node and the destination node:
a non-transitory computer-readable storage medium comprising a SIP policy database that stores QoS policies for nodes and applications serviced by a router, and a SIP connection database that stores information used to identify connections for the serviced nodes;
a Deep Packet Inspection (DPI) processor configured to intercept a SIP control message transferred between the source node and the destination node over a control channel, extract connection information regarding the SIP connection from from at least one of layers 4 through 7 of the OSI model of the control message, and store the connection information in the SIP connection database; and
a general processor that modifies the QoS for packets belonging to the SIP connection at one or more network nodes between the transmitter and the destination node using QoS information obtained by querying the SIP policy database using the connection information in the SIP connection database.
2. The system for implementing QoS for a SIP connection between a source node and a destination node according to claim 1 , wherein the receiver, the transmitter, the computer-readable storage medium, the DPI processor, and the general processor are integrated into the router.
3. The system for implementing QoS for a SIP connection between a source node and a destination node according to claim 1 , wherein the receiver, the transmitter, the computer-readable storage medium, and the general processor are integrated into the router and the DPI processor is an external device in communication with the router.
4. The system for implementing QoS for a SIP connection between a source node and a destination node according to claim 1 , wherein:
the DPI processor is further configured to process user data associated with the control channel to identify an end-user application, and
the general processor modifies the QoS for packets belonging to the connection using QoS information obtained by querying the SIP policy database using the connection information and the identified end-user application.
5. The system for implementing QoS for a SIP connection between a source node and a destination node according to claim 1 , wherein the QoS policies stored in the SIP policy database specify whether QoS may be provided for a particular user associated with the source node.
6. The system for implementing QoS for a SIP connection between a source node and a destination node according to claim 1 , wherein the QoS policies stored in the SIP policy database specify whether. QoS may be provided for a particular application associated with the SIP connection.
7. The system for implementing QoS for a SIP connection between a source node and a destination node according to claim 1 , wherein the QoS policies stored in the SIP policy database are based on at least one of an application associated with the connection, a source of the connection, a destination of the connection, and a time of day.
8. The system for implementing QoS for a SIP connection between a source node and a destination node according to claim 1 , wherein the connection information extracted by the DPI processor comprises at least one of an application associated with the connection, a compression scheme, a media type, a source of the connection, a destination of the connection, and a port number.
9. The system for implementing QoS for a SIP connection between a source node and a destination node according to claim 1 , wherein the general processor modifies the QoS for packets belonging to the connection by marking user data packets associated with the connection using at least one of a Differentiated Services Code Point (DSCP) marking and a Type of Service (ToS) marking.
10. The system for implementing QoS for a SIP connection between a source node and a destination node according to claim 1 , wherein the general processor modifies the QoS for packets belonging to the connection by generating a Resource Reservation Protocol (RSVP) message for transmission along a path associated with the connection.
11. The system for implementing QoS for a SIP connection between a source node and a destination node according to claim 1 , wherein the general processor modifies the QoS for packets belonging to the connection by redirecting packets trough pre-established network connections associated with different QoS guarantees based on the QoS granted for the connection.
12. The system for implementing QoS for a SIP connection between a source node and a destination node according to claim 1 , wherein the source node is a user agent client in a Session Initiation Protocol (SIP) connection.
13. The system for implementing QoS for a SIP connection between a source node and a destination node according to claim 1 , wherein the destination node is a user agent server in a Session Initiation Protocol (SIP) connection.
14. A method of providing QoS for Session Initiation Protocol (SIP) connections between a source node and a destination node, the method comprising:
forwarding a request message from the source node to the destination node over a control channel, the request message indicating that the source node seeks to establish a SIP connection with the destination node;
forwarding a response from the destination node to the source node, the response indicating acceptance of the SIP connection by the destination node;
intercepting the response by a Deep Packet Inspection (DPI) processor;
extracting, by the DPI processor, connection information regarding the SIP connection from at least one of layers 4 through 7 of the OSI model of the response; and
modifying the QoS for packets belonging to the SIP connection at one or more network nodes between the DPI processor and the destination node, the QoS based at least in part on the connection information extracted by the DPI processor.
15. The method of providing QoS for SIP connections between a source node and a destination node according to claim 14 , further comprising:
processing, by the DPI processor, user data associated with the control channel to identify an end-user application, and
modifying the QoS for packets belonging to the connection based at least in part on the connection information extracted by the DPI processor and the end-user application identified by the DPI processor.
16. The method of providing QoS for SIP connections between a source node and a destination node according to claim 14 , wherein the request message is a Session Initiation Protocol (SIP) invite request comprising a media authorization token and a Session Description Protocol (SDP) field.
17. The method of providing QoS for SIP connections between a source node and a destination node according to claim 14 , wherein the response is a SIP ringing response.
18. The method of providing QoS for SIP connections between a source node and a destination node according to claim 14 , further comprising a step of determining whether. QoS provisioning is allowed for the connection by querying a SIP policy database using the connection information.
19. The method of providing QoS for SIP connections between a source node and a destination node according to claim 14 , further comprising a step of determining how to modify the QoS by querying a SIP policy database using the connection information.
20. The method of providing QoS for SIP connections between a source node and a destination node according to claim 14 , wherein the connection information is extracted by the DPI processor from at least one of a header field and an SDP field in the response.
21. The method of providing QoS for SIP connections between a source node and a destination node according to claim 14 , further, comprising a step of storing the connection information extracted by the DPI processor in a SIP connections database.
22. The method of providing QoS for SIP connections between a source node and a destination node according to claim 14 , wherein the step of modifying the QoS comprises:
querying a SIP policy database using the connection information;
generating at least one Resource Reservation Protocol (RSVP) message based on QoS information obtained from the SIP policy database; and
sending RSVP messages to reserve bandwidth along a path associated with the connection.
23. The method of providing QoS for SIP connections between a source node and a destination node according to claim 14 , wherein the step of modifying the QoS comprises:
querying a SIP policy database using the connection information; and
remarking packets belonging to the connection based on QoS information obtained from the policy database.
24. The method of providing QoS for SIP connections between a source node and a destination node according to claim 23 , wherein the step of remarking packets tickets utilizes a Differentiated Service Code Point (DSCP) marking.
25. The method of providing QoS for SIP connections between a source node and a destination node according to claim 23 , wherein the step of remarking packets utilizes a Type of Service (ToS) marking.