Control in a data access transport service

• US 6,070,192 A
• Filed: 12/24/1997
• Issued: 05/30/2000
• Est. Priority Date: 05/30/1997
• Status: Expired due to Fees

• Current Assignee: Nortel Networks Limited (Nortel Networks Corporation)
• Original Assignee: Nortel Networks Corporation
• Inventors: Myers, Robert, Holt, Robert Hugh, Gibson, Robert Thomas
• Primary Examiner(s): Maung, Zarni
• Assistant Examiner(s): Romero, Almari
• Application Number:
  US08/997,799
• Time in Patent Office: 888 Days
• Field of Search: 709/227, 709/229, 709/224, 709/220, 709/200, 713/202
• US Class Current: 709/227
• CPC Class Codes: H04L 12/2856 Access arrangements, e.g. Internet access asynchronous transfer mode networks H04L12/5601; broadband local area networks H04L12/2801; optical access or distribution networks H04Q11/0067; access to open networks H04L12/5691; digital subscriber line end-user equipment and bit-level processing of data on a PSTN-based network H04M11/00; home network gateways H04L12/2834; wireless access networks H04W
• CPC Class Codes: H04L 12/2872 Termination of subscriber connections
• CPC Class Codes: H04L 47/125 by balancing the load, e.g. traffic engineering
• CPC Class Codes: H04L 47/70 Admission control; Resource allocation
• CPC Class Codes: H04L 47/746 Reaction triggered by a failure
• CPC Class Codes: H04L 47/781 Centralised allocation of resources
• CPC Class Codes: H04L 47/822 Collecting or measuring resource availability data
• CPC Class Codes: H04L 47/825 Involving tunnels, e.g. MPLS
• CPC Class Codes: H04L 47/828 Allocation of resources per group of connections, e.g. per group of users
• CPC Class Codes: H04L 69/14 Multichannel or multilink protocols
• CPC Class Codes: H04L 9/40 Network security protocols
• CPC Class Codes: H04Q 11/0435 Details
• CPC Class Codes: H04Q 2213/13039 Asymmetrical two-way transmission, e.g. ADSL, HDSL
• CPC Class Codes: H04Q 2213/1307 Call setup
• CPC Class Codes: H04Q 2213/13141 Hunting for free outlet, circuit or channel
• CPC Class Codes: H04Q 2213/13174 Data transmission, file transfer
• CPC Class Codes: H04Q 2213/13196 Connection circuit/link/trunk/junction, bridge, router, gateway
• CPC Class Codes: H04Q 2213/13204 Protocols
• CPC Class Codes: H04Q 2213/13209 ISDN
• CPC Class Codes: H04Q 2213/13298 Local loop systems, access network
• CPC Class Codes: H04Q 2213/13389 : LAN, internet
• CPC Class Codes: H04Q 3/0016 : Arrangements providing connection between exchanges

Abstract

In a Data Access Transport Service (DATS), Data Service Providers (DSPs) share dial-in access (e.g. analog modem or Integrated Services Digital Network (ISDN) access) resources from a common pool maintained by a Local Exchange Carrier (LEC) (or potentially a DSP. A system is disclosed wherein a Network Controller (NC) performs the role of DSP service partitioning, quota enforcement, and resource load balancing to ensure that a DATS provider can provide a high quality of service (availability, response time & consistent bandwidth) to subscribed DSPs and their end-users. The Network Controller assists in Internet Data call establishment and tear-down, with the ability to refuse calls when the associated DSP has exceeded its service quota. The Network Controller also assists in the routing of calls to one of the DSPs Network Gateways (or data routers), using a load balancing scheme that maintains a pre-defined relative load on given DSP Network Gateways. The Network Controller will also provide an implementation that supports Multilink Point-to-Point Protocol (MLP) and 56 kbps data calls for ISDN BRI access. Additionally, the Network Controller will perform such functions as statistics collection, and network element administrative control. The Network Controller can be positioned to provide similar service control functionality with higher speed access technologies such as Asymmetric Digital Subscriber Loop (ADSL) and high-speed cable modems.

Claims

1. A data access transport system comprising a plurality of network access servers and a network controller connected to the network access servers;

each network access server being operable;

to send a connection setup request to the network controller on receipt of a data call before answering the data call, the connection setup request specifying a data service provider to which a connection is requested; and

to receive a connection setup response from the network controller, the connection setup response indicating whether the requested connection is to be completed;

to respond to a connection setup response indicating that the connection is to be completed by answering the data call and initiating a connection to the specified data service provider; and

to respond to a connection setup response indicating that the connection is not to be completed by initiating a busy indication; and

the network controller being operable;

to receive a connection setup request from any of the network access servers;

to determine whether a quantity of network resources currently used by the data service provider specified in the connection setup request is less than an service quota assigned to the data service provider; and

to send a connection setup response to the network access server which sent the connection setup request, the connection setup response indicating that the requested connection is to be completed when the quantity of network resources currently used by the data service provider is less than the assigned service quota and the connection setup response indicating the requested connection is not to be completed when the quantity of network resources currently used by the data service provider is not less than the assigned service quota.

2. A system as defined in claim 1, wherein each network access server is operable:

to detect termination of data calls; and

to send a connection release request to the network controller upon detection of termination of a data call.

3. A network controller for use in a data access transport system comprising a plurality of network access servers connected to the network controller, the network controller comprising:

means for receiving a connection setup request from any of the network access servers;

means for determining whether a quantity of network resources currently used by the data service provider specified in the connection setup request is less than an service quota assigned to the data service provider; and

means for sending a connection setup response to the network access server which sent the connection setup request, the connection setup response indicating that the requested connection is to be completed when the quantity of network resources currently used by the data service provider is less than the assigned service quota and the connection setup response indicating the requested connection is not to be completed when the quantity of network resources currently used by the data service provider is not less than the assigned service quota.

4. A network controller as defined in claim 3, further comprising:

means for maintaining a count of active calls to each data service provider served by the data access transport system;

means for maintaining a count of active calls served by each network gateway served by the data access transport system; and

means for selecting a network gateway for completing a connection to a data service provider based on the counts of active calls served by each network gateway connected to the data service provider;

the means for sending a connection setup response being responsive to the means for selecting a network gateway to send a connection setup response specifying the selected network gateway.

5. A network controller as defined in claim 4, further comprising means for maintaining a record of tunnels currently connected between network access servers and network gateways, the means for selecting a network gateway being operable to select a network gateway based on the counts of active calls served by each network gateway and the record of tunnels currently connected between network access servers and network gateways.

6. A network controller as defined in claim 4, further comprising means for recognizing call setup requests corresponding to segments of a MLP call, the means for selecting a network gateway for completing a connection to a data service provider being responsive to the means for recognizing call setup requests corresponding to segments of a MLP call to select the same network gateway for all segments of a MLP call.

7. A network controller as defined in claim 3, further comprising means for recognizing call setup requests corresponding to data calls requiring 56 kbps service, the means for sending a connection setup response being responsive to the means for recognizing call setup requests corresponding to data calls requiring 56 kbps service to send a connection setup response indicating that 56 kbps service is required.

8. A network controller as defined in claim 3, further comprising:

means for deriving operational data from at least one of connection setup requests, connection setup responses, connection release requests, connection release acknowledgements and error conditions detected by the network controller; and

means for recording at least some of the derived operational data.

9. A network controller as defined in claim 4, further comprising means for flagging network gateways as disabled, the means for selecting a network gateway responding to the means for flagging network gateways as disabled by not selecting any network gateway currently flagged as disabled.

10. A network controller as defined in claim 9, wherein the means for flagging network gateways as disabled is responsive to receipt of a message from a network access server indicating a failure to open a connection to a particular network gateway to flag that particular network gateway as disabled.

11. A network controller as defined in claim 10, wherein the means for selecting a network gateway is responsive to receipt of the message indicating a failure to open a connection to a particular network gateway to select another network gateway for connection of the call.

12. A network controller as defined in claim 3, further comprising means for flagging groups of directory numbers as disabled, each directory number group comprising at least one directory number, the means for sending a connection setup response being responsive to the means for flagging directory number groups as disabled to send connection setup responses indicating that connections are not to be completed in response to connection setup requests specifying directory numbers in directory number groups which are flagged as disabled.

13. A network controller as defined in claim 3, further comprising means for flagging network access servers as disabled, the means for sending a connection setup response being responsive to the means for flagging network access servers as disabled to send connection setup responses indicating that connections are not to be completed in response to connection setup requests sent by network access servers which are flagged as disabled.

14. A network access server for use in a data access transport system comprising a network controller connected to the network access server, comprising:

means for sending a connection setup request to the network controller on receipt of a data call before answering the data call, the connection setup request specifying a data service provider to which a connection is requested;

means for receiving a connection setup response from the network controller, the connection setup response indicating whether the requested connection is to be completed;

means for answering the data call and initiating a connection to the specified data service provider in response to a connection setup response indicating that the connection is to be completed; and

means for initiating a busy indication in response to a connection setup response indicating that the connection is not to be completed.

15. A network access server as defined in claim 14, further comprising:

means for detecting termination of data calls; and

means for sending a connection release request to the network controller upon detection of termination of a data call.

16. A network access server as defined in claim 14, wherein the means for initiating a connection to the specified data service provider initiates a connection via a network gateway specified in the connection setup response.

17. A network access server as defined in claim 14, further comprising means for sending a message the network controller upon failure to complete a connection to a particular network gateway, the message specifying the particular network gateway.

18. A network access server as defined in claim 14, further comprising means responsive to a signal indicating that the network access server is disabled to send a signal to an access network indicating that access channels of the network access server are unavailable for use.

19. A network access server as defined in claim 18, further comprising means responsive to a signal indicating that the network access server is re-enabled to send a signal to an access network indicating that access channels of the network access server are available for use.

20. A method for operating a data access transport system comprising a plurality of network access servers and a network controller connected to the network access servers, the method comprising:

sending a connection setup request from a network access server to the network controller on receipt of a data call before answering the data call, the connection setup request specifying a data service provider to which a connection is requested;

determining at the network controller whether a quantity of network resources currently used by the data service provider specified in the connection setup request is less than a service quota assigned to the data service provider;

sending a connection setup response from the network controller to the network access server which sent the connection setup request, the connection setup response indicating that the requested connection is to be completed when the quantity of network resources currently used by the data service provider is less than the assigned service quota and the connection setup response indicating the requested connection is not to be completed when the quantity of network resources currently used by the data service provider is not less than the assigned service quota;

responding at the network access server to a connection setup response indicating that the connection is to be completed by answering the data call and initiating a connection to the specified data service provider; and

responding at the network access server to a connection setup response indicating that the connection is not to be completed by initiating a busy indication.

21. A method as defined in claim 20, further comprising:

detecting termination of a data call at a network access server; and

sending a connection release request to the network controller upon detection of the termination.

22. A method for operating a network controller for use in a data access transport system comprising a plurality of network access servers connected to the network controller, the method comprising:

receiving a connection setup request from any of the network access servers;

determining whether a quantity of network resources currently used by the data service provider specified in the connection setup request is less than a service quota assigned to the data service provider; and

sending a connection setup response to the network access server which sent the connection setup request, the connection setup response indicating that the requested connection is to be completed when the quantity of network resources currently used by the data service provider is less than the assigned service quota and the connection setup response indicating the requested connection is not to be completed when the quantity of network resources currently used by the data service provider is not less than the assigned service quota.

23. A method as defined in claim 22, further comprising:

maintaining a count of active calls to each data service provider served by the data access transport system;

maintaining a count of active calls served by each network gateway served by the data access transport system; and

selecting a network gateway for completing a connection to a data service provider based on the counts of active calls served by each network gateway connected to the data service provider;

the step of sending a connection setup response comprising sending a connection setup response specifying the selected network gateway.

24. A method as defined in claim 23, further comprising maintaining a record of tunnels currently connected between network access servers and network gateways, the step of selecting a network comprising selecting a network gateway based on the counts of active calls served by each network gateway and the record of tunnels currently connected between network access servers and network gateways.

25. A method as defined in claim 23, further comprising recognizing call setup requests corresponding to segments of a MLP call, the step of selecting a network gateway for completing a connection to a data service provider comprising selecting the same network gateway for all segments of a MLP call.

26. A method as defined in claim 22, further comprising recognizing call setup requests corresponding to data calls requiring 56 kbps service, the step of sending a connection setup response comprising sending a connection setup response indicating that 56 kbps service is required.

27. A method as defined in claim 22, further comprising:

deriving operational data from at least one of connection setup requests, connection setup responses, connection release requests, connection release acknowledgements and error conditions detected by the network controller; and

recording at least some of the derived operational data.

28. A method as defined in claim 22, further comprising flagging network gateways as disabled, the step of selecting a network gateway comprising not selecting any network gateway currently flagged as disabled.

29. A method as defined in claim 22, further comprising flagging directory number groups as disabled, each directory number group comprising at least one directory number, the step of sending a connection setup response comprising sending a connection setup response indicating that a connection is not to be completed for any connection setup request specifying a directory number in a directory number group which is flagged as disabled.

30. A method as defined in claim 22, further comprising flagging network access servers as disabled, the step of sending a connection setup response comprising indicating that connections are not to be completed in response to connection setup requests sent by network access servers which are flagged as disabled.

31. A method for operating a network access server in a data access transport system comprising a network controller connected to the network access server, comprising:

sending a connection setup request to the network controller on receipt of a data call before answering the data call, the connection setup request specifying a data service provider to which a connection is requested;

receiving a connection setup response from the network controller, the connection setup response indicating whether the requested connection is to be completed;

answering the data call and initiating a connection to the specified data service provider in response to a connection setup response indicating that the connection is to be completed; and

initiating a busy indication in response to a connection setup response indicating that the connection is not to be completed.

32. A method as defined in claim 31, further comprising:

detecting termination of data calls; and

sending a connection release request to the network controller upon detection of termination of a data call.

33. A method as defined in claim 31, wherein the step of initiating a connection to the specified data service provider comprises initiating a connection via a network gateway specified in the connection setup response.