US20070165650A1

US20070165650A1 - System and Method for Managing Network Elements in an ATM Network

Info

Publication number: US20070165650A1
Application number: US11/693,917
Authority: US
Inventors: Earl Meggison; Randy Young; David Rutland
Original assignee: Meggison Earl C; Young Randy S; David Rutland
Current assignee: AT&T Intellectual Property I LP
Priority date: 2002-06-19
Filing date: 2007-03-30
Publication date: 2007-07-19
Also published as: US7203168B1

Abstract

Reporting tools used to manage an asynchronous transfer mode (ATM) network. Tools include a trunk inventory reporting tool, a trunk utilization reporting tool, an exceptions reporting tool and a flow control processor activation utility. Reports generated by these the tools include information about the operation and capacity of trunks, switches and user network interfaces.

Description

BACKGROUND

1. Field of the Invention
The present invention relates generally to broadband network management, and more particularly to management of asynchronous transfer mode (ATM) networks.
2. Background of the Invention
Traditionally, telecommunications service providers have offered basic services such as local and long distance exchange services for voice communications. More recently, with the explosive growth of the Internet and other data services, telecommunications service providers have expanded beyond basic telephone services to the provision of very high bandwidth network services. Examples of such newer network services include, for example, digital subscriber line (DSL), asymmetric digital subscriber line (ADSL), integrated services digital network (ISDN) digital subscriber line (IDSL), and the like. The underlying transmission facility supporting such high bandwidth networks may comprise an asynchronous transfer mode (ATM) network as shown in FIG. 1.
ATM network or “cloud” 10 in FIG. 1 comprises one or more ATM switches 11-15. The switches may be interconnected in any suitable manner to provide redundancy in the network and to ensure high speed transmission of network packets. ATM switches are well-known in the art and are available from numerous switch vendors, including, for example, Lucent, Cisco and Nortel.
ATM switch vendors generally provide off-the-shelf network management utilities that may be used to manage ATM network elements. A problem with conventional ATM network management tools, however, is the lack of adequate reporting capabilities providing information needed to properly manage a large-scale ATM network. For example, conventional ATM network management utilities do not provide trunk inventory reports, trunk utilization reports and exception reports.
Another problem with conventional ATM network management utilities is the lack of an activation utility to activate flow control and flow control attributes for eligible User Network Interfaces (UNIs).

SUMMARY OF THE INVENTION

The present invention provides a plurality of reporting tools that may be used to manage an ATM network. In a first embodiment, a trunk inventory report for managing trunks terminated on an ATM switch is provided. A header section of the trunk inventory report comprises at least one of a report title, a report date, a switch name for the ATM switch, a switch Internet Protocol (IP) address for the ATM switch, and a number of trunks terminated on the ATM switch. A body section of the trunk inventory includes a record for each trunk terminated on the ATM switch. The information in each record may be gathered from a switch management database and a network management information database. The trunk inventory report may be organized according to a pre-determined format to present the information in a usable format. Examples of data that may be gathered from the switch management database include a trunk name, data values associated with the trunk-end terminated on the ATM switch identified in the report header, and values associated with the trunk-end terminated on a second ATM switch.
In a second embodiment, a trunk utilization report for managing trunks terminated on an ATM switch is provided. A header section of the trunk utilization report comprises at least one of a report title, a report date, a switch name for the ATM switch, a switch IP address for the ATM switch, a period start date for the report and a period end date for the report. A body section of the trunk utilization report includes a record for each trunk terminated on the ATM switch. The information in each record may be gathered from a switch management database and a network management information database. Each record also includes a trunk utilization rate based on a cells incoming value and a cells outgoing value.
In a third embodiment, an exception report for identifying and managing exceptions in network elements associated in an ATM network is provided. A header section of the exception report includes at least one of an exception class, and an exception criteria. The exception class and exception criteria are selectable by a user of the report. A body section of the exception report includes a record for each exception associated with the selected exception class and exception criteria. The information in each record may be gathered from a switch management database and a network management information database. Examples of exception classes include a threshold class and an attribute class. Examples of exception criteria for threshold class exceptions include: virtual circuits per physical port, virtual circuits per card, virtual circuits per switch, network service providers per card, and thread limitations. Examples of exception criteria for attribute class exceptions include: card-level, Resource Management (RM)-cell generation and termination, Explicit Forward Congestion Indication bit check, physical port buffer size, Early Packet Discard (EPD) enabled (all of which are all well known industry terms describing ATM standard features), switch-level, virtual circuits mapped across a trunk, quality of service match for both ends, quality of service parameters exceeds thresholds, trunk is down, and trunk type is management-only.
In a fourth embodiment of the present invention, a Flow Control Processor (FCP) activation utility is provided. The utility preferably generates a report with the same type header descriptions provided above. The differences start after the switch name. At this point the report identifies the Cards, Physical Ports, Logical Ports, or Virtual Circuits that do not meet the defined standard, such that an exception report is provided. The exception class and exception criteria are selectable by a user of the report. A body section of the exception report includes a record for each exception associated with the selected exception class and exception criteria. The information in each record may be gathered from a switch management database and a network management information database. Examples of exception classes include a threshold class and an attribute class. Examples of exception criteria for threshold are as mentioned above the Cards, Physical Ports, Logical Ports, or Virtual Circuits. Flow Control attributes are that it is enabled at the card level. At the physical port there is a rate profile table that is modifiable. The logical level has attributes at relating to Cell Generation that are modifiable based on the classification of a trunk or UNI. A virtual circuit will have EPD enabled or not. The report is preferably designed to provide exceptions based on the level requested by the user.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a schematic diagram showing a typical ATM network in which the present invention may be implemented.
FIG. 2 is a schematic diagram of an exemplary trunk inventory report according to the present invention.
FIG. 3A is a table identifying exemplary fields associated with the A-end of trunks that may be reported in a trunk inventory report according to the present invention.
FIG. 3B is a table identifying exemplary generic fields that may be reported in a trunk inventory report according to the present invention.
FIG. 3C is a table identifying exemplary tuning parameters that may be reported in a trunk inventory report according to the present invention.
FIG. 4 is a schematic diagram of an exemplary trunk utilization report according to the present invention.
FIG. 5 is a schematic diagram of an exemplary exception report according to the present invention.
FIG. 6A is a table identifying exemplary threshold criteria and associated fields that may be reported in an exception report according to the present invention.
FIG. 6B is a table identifying exemplary attribute criteria and associated fields that may be reported in an exception report according to the present invention.
FIG. 7 is a flow diagram of exemplary steps for setting flow control attributes in an embodiment of the present invention.

DETAILED DESCRIPTION OF THE INVENTION

The present invention provides a system and method for managing network elements in an ATM network by providing detailed reports for specific areas of concern to a network manager. The invention further provides an activation utility for setting flow control attributes. The various reports and utility are described in greater detail in the sections below.
Trunk Inventory Report
FIG. 2 shows an exemplary trunk inventory report 200 according to the present invention. Trunk inventory report 200 includes header section 202 and body section 204. Header section 202 provides the general information about the report. Each of the fields in header section 202 are optional fields that may be included to enhance the usability of the report. Report title field 206 may be used to identify the report. Date field 208 may be used to identify the date the report was generated. Switch name field 210 may be used to identify the switch associated with the trunk inventory report. Switch IP address field 212 may be used to identify the IP address of the switch. Number of trunks field 214 may be used to indicate the number of trunks reported.
Body section 204 includes a plurality of fields that may be used to provide detailed information about attributes of each trunk identified in the report. Some of the information used to populate the various fields in trunk inventory report 200 may be retrieved from vendor-specific network management databases. For example, if the ATM network switches are provided by Lucent, some of the data may be gathered from the NavisCore™ database via an application protocol interface (API) interface that will provide the proper naming conventions used to describe each trunk. This allows the report user to determine the offending trunk to execute the appropriate correction processes. Other data may be retrieved directly from the switch using the well-known simple network management protocol (SNMP). Those skilled in the art will appreciate that the present invention is applicable to ATM switches in a “vendor agnostic” way. Thus, while Navis refers to a specific network management system (NMS), or element management system (EMS) that is used by a particular vendor (Lucent) to manage its ATM switch, the present invention is generically applicable to ATM switches, ATM network elements, EMSs and NMSs generally.
Without the instant invention, an ATM is operated in the blind. Managers react to customer trouble reports rather than react to an information-based system that indicates the need to proactively respond to a threshold/exception report. The present invention is thus a process improvement initiative to manage the ATM business in a way that has a positive impact on customer service.
Referring again to FIG. 2, A-end identifier field 216 identifies the Logical Port on the local end. That is, the Logical Port on the same switch for which the report has been generated. B-end identifier field 218 identifies the Logical Port on the distant switch. Trunk name field 220 identifies the name of the trunk. Bandwidth field 222 is the bandwidth of the trunk. This value will typically be the maximum bandwidth of the two ends. That is, the bandwidth will be the larger of the bandwidths for the Logical Port of A-end and the Logical Port of the B-end, since the bandwidth at the Logical Port is symmetrical. VPN ID field 224 identifies the name of the virtual private network (VPN) to which the trunk belongs. The report also includes a plurality of fields for providing detailed information about each end of the trunk.
Fields 226 and 228 pertain to the A-end of the trunk and fields 230 and 232 pertain to the B-end. FIG. 2 shows just two of the many fields that may be included in the trunk inventory reports. Table 300 in FIG. 3A provides more detailed information about other such fields that may be included in the report. Table 300 only shows those fields associated with the A-end. It is to be understood that similar fields associated with the B-end may be included in the report. Table 302 in FIG. 3B shows other fields that may be included in the report.
Field 234 in FIG. 2 may be used to report various tuning parameters. Table 304 in FIG. 3C identifies some of the tuning parameters that may be included in a trunk inventory report according to the present invention.
Traffic type field 236 identifies the type of traffic allowed over an Interswitch Trunk. For example, traffic type 236 may indicate that all user data traffic is allowed, management traffic only is allowed, or management and user data traffic.
Administrative cost field 238 is used to identify the assigned costs for each trunk. This value may be used when routing circuits where trunks with the lowest costs are preferred.
Trunk status field 240 provides the current status of the trunk. Examples of status indicators include Administrative Status Up, Administrative Status Down, Operational Status Up, or Operational Status Down.
In a preferred embodiment, trunk inventory report 200 is generated by an application program running on a server identified as the location to house the utility. Trunk inventory report 200 is preferably generated in an ASCII format, and preferably has tab delimiters between fields.
Trunk Utilization Report
A trunk utilization report according to the present invention may be automatically generated by an application program. In a preferred embodiment, the application program may be run on a periodic basis to provide traffic statistics for the trunks in the network. The application may be scheduled to run using any application scheduling program. For example, on a UNIX-based system, the cron daemon may be used. In a Windows NT-based system, the Scheduled Task application of Windows may be used.
Trunk utilization is calculated based on traffic statistics over a defined period of time. The calculation is based on two sets of traffic data: a first set of data collected at the beginning of the period and a second set of traffic data collected at the end of the period. The application program preferably gathers traffic statistics data from each switch and saves the data in a text file. The application program then calculates a utilization rate for each trunk for the current period based on the most recent data collected and the data collected at the end of the last period. The application program then generates the trunk utilization report for the period.
FIG. 4 shows an exemplary trunk utilization report 400 according to the present invention. Trunk utilization report 400 includes header section 402 and body section 404. Header section 402 provides the general information about the report. Each of the fields in header section 402 are optional fields that may be included to enhance the usability of the report. Report title field 406 may be used to identify the report. Date field 408 may be used to identify the date the report was generated. Switch name field 410 may be used to identify the switch associated with the trunk inventory report. Switch IP address field 412 may be used to identify the IP address of the switch. Period start date field 414 may be used to indicate the beginning of the period (i.e., the date the first set of data was generated) and period end date field 416 be used to indicate the end of the period (i.e., the date the second set of data was generated).
Report body 404 includes several fields of data that may be used in the trunk utilization report. Some of these fields are the same as those included in trunk inventory report 200. For example, trunk name field 418 identifies the name of the trunk. Trunk status field 420 provides the current status of the trunk, and, traffic type field 422 identifies the type of traffic allowed over an Interswitched Trunk.
Cells incoming field 424 indicates the number of cells incoming to Logical Port A (i.e., the A-end of the trunk) and the end of the period minus the number of cells incoming to Logical Port A at the beginning of the period. Cells outgoing field 426 indicates the number of cells outgoing from Logical Port A at the end of the period minus the number of cells outgoing from Logical Port A at the beginning of the period. Utilization rate field 428 is calculated by dividing the cells incoming minus cells outgoing by the duration divided by the trunk bandwidth. For example, if the trunk bandwidth for trunk TRI shown in row 430 is 10,000 cells per minute and the duration of the period is one week, the utilization rate would be 93.27%. (62321000 cells−156345000 cells)/10080 minutes/10,000 cells/minute).
Cells discarded field 432 is determined from a data register in the switch. The process to calculate cells discarded is similar to the process described above, namely, a beginning number combined with an ending number to determine a difference. A similar calculation is performed for cells lost field 434.
The source of data for the information provided in trunk utilization report 400 is SNMP for each field, except for trunk name field 418 and (cells discarded field 432 and cells lost field 334) cells discarded and lost are reported by the switch to the application. Data for trunk name field 418 is gathered from, e.g., the NavisCore database and data for cells discarded field 432 and cells lost field 434 is gathered as described above.
Exception Report
An exception report according to the present invention may bc used to report threshold exceptions and/or attribute exceptions. As used herein threshold exceptions are those items that exceed an established limit used to trigger relief processes eliminate the threshold exception. The threshold limits may be, for example, documented in a set of capacity engineering guidelines. This guidelines may be changed as needed to facilitate network architecture or design changes or response to capital (dollar) constraints. The threshold criteria is modifiable. As used herein, attribute exceptions are those items that do not meet the desired configuration profile established by documented engineering guidelines. These guidelines may also be changed as needed to facilitate network architecture or design changes. Preferably, the exception criteria is modifiable. The exceptions report may include exceptions examined at the switch, Physical Port, Logical Port, virtual circuit and trunk levels. All of the data reported in the exception report is gathered from the switch or an element management system database, such as NavisCore.
FIG. 5 shows an exemplary exception report 500 according to the present invention. Exception report 500 includes header section 502 and body section 504. Header section 502 provides the general information about the report. Each of the fields in header section 502 are optional fields that may be included to enhance the usability of the report. Report title field 506 may be used to identify the report. Date field 508 may be used identify the date the report was generated. Exception class field 510 may be used to identify the class of exceptions reported in the exception report. Exceptions may be classified either as “Threshold Exceptions” or “Attribute Exceptions.” Exception criteria field 512 may be used to identify specific criteria reported in exception report 500. Exemplary criteria that may be reported in exception report 500 are identified in Tables 600 and 602 in FIGS. 6A and 6B, respectively. Table 600 identifies exemplary threshold criteria and Table 602 identifies exemplary attribute criteria. The expectation is that attributes in these tables are defined by an engineering design process that determines the criteria. This makes the criteria modifiable to match design standards.
Report body 504 includes several fields of data that may be used in the exception report and may vary depending on the exception being reported. Exemplary data fields associated with each exception criteria is provided in Tables 600 and 602. For example, if the exception criteria being reported is that the card has a FCP enabled and the virtual circuits (VCs) per card exceeds the pre-determined threshold amount, fields 518-426 may be used. In this case, switch name field 518 identifies the name of the switch for which an exception has been identified. Switch IP address field 520 may be used to provide the IP address of the switch named in field 518. Slot number field 522, card type field 524 and number of VCs field 526 provide additional information about the exception.
In addition to the criteria described above, other criteria may be defined by a network manager using the system and methods of the present invention. Preferably, such other criteria may be defined in a configuration file that may be edited by the user. Other criteria may include, for example, exceptions that should be reported but are not considered to be fatal exceptions. By including such non-critical exceptions in the exception report, the network manager may proactively manage the network to prevent fatal exceptions.
FCP Activation Utility
This utility may be used to activate the flow control for eligible UNIs, set the flow control attributes of the trunks to “safe” or “designed” values while the UNIs are being set up, and set the flow control attributes of the trunks to their “final” values once both (UNI) ends of the flow-control-eligible end-to-end path have their flow control attributes configured. Control is the control of traffic through the ATM network that ensures fairness in traffic balancing between virtual circuits and virtual paths in the ATM network. Control is desired since the ATM vendor community does not provide the necessary knowledge for appropriate and effective management. With improper controls the resulting service issues outweigh the benefit of flow control. It should be apparent that the present invention facilitates management and control of ATM traffic flow.
In an embodiment of the present invention, the FCP Activation Utility may use an algorithm such as shown in the flow diagram in FIG. 7 to set the flow control attributes to match the designed or “safe” limits. In step 700, an eligible UNI is located. In this algorithm, an eligible UNI is any UNI connection on an ATM switch in which FCP needs to be enabled. In step 702, the flow control attributes of the trunks are set to design values. In step 704, the FCP for the eligible UNI is activated. For example, when the FCP is activated, the FCP may be initiated using the following settings: Initial Cell Rate (ICR) Constant 0; Rate Profiles tables are loaded; Resource Management (RM)-cell Interval=100 ms; Idle Virtual Circuit factor=8. In step 706, the flow control values are set to their final values. For example, the final values on the trunk for RM-cell settings may be: Generation=Call Control Resource Management (CCRM); and Termination=CCRM. For UNI, the final values may be: Generation=No Loop, and Termination=CCRM and Backward Control Management (BCM). More eligible UNIs are obtained through a loop back process indicated at step 708.
The foregoing disclosure of the preferred embodiments of the present invention has been presented for purposes of illustration and description. It is not intended to be exhaustive or to limit the invention to the precise forms disclosed. Many variations and modifications of the embodiments described herein will be apparent to one of ordinary skill in the art in light of the above disclosure. The scope of the invention is to be defined only by the claims appended hereto, and by their equivalents.
Further, in describing representative embodiments of the present invention, the specification may have presented the method and/or process of the present invention as a particular sequence of steps. However, to the extent that the method or process does not rely on the particular order of steps set forth herein, the method or process should not be limited to the particular sequence of steps described. As one of ordinary skill in the art would appreciate, other sequences of steps may be possible. Therefore, the particular order of the steps set forth in the specification should not be construed as limitations on the claims. In addition, the claims directed to the method and/or process of the present invention should not be limited to the performance of their steps in the order written, and one skilled in the art can readily appreciate that the sequences may be varied and still remain within the spirit and scope of the present invention.

Claims

1-10. (canceled)

11. A computer-readable medium having computer-executable instruction to cause the computer to perform steps in a process for setting flow control attributes in an ATM network, the instruction comprising:

locate an eligible user network interface (UNI);

set flow control attributes of trunks connected between the UNI and an ATM switch to predetermined values;

activate a flow control processor for the eligible UNI; and

set flow control values to a final setting based at least in part on information received from the flow control processor.

12. The computer-readable medium of claim 11, wherein the flow control values facilitate management and control of traffic flow in the ATM network by ensuring fair traffic balancing between virtual circuits and virtual paths in the ATM network.

13. The computer-readable medium of claim 11, further comprising instructions to repeat said process for a plurality of UNIs.

14. The computer-readable medium of claim 11, wherein the predetermined values are used during the set up of the UNI.

15. The computer-readable medium of claim 11, wherein an eligible UNI is any UNI connection on an ATM switch in which the flow control processor is required to be activated.

16. The computer-readable medium of claim 12, wherein the final flow control values for a UNI setting comprise at least one of setting a “Generation” element to “No Loop” and setting a “Termination” element to “CCRM and Backward Control Management”.

17. The computer-readable medium of claim 12, wherein the final flow control values for an RM-cell setting comprise at least one of setting a “Generation” element to “Call Control Resource management (CCRM)” and a “Termination” element to “CCRM”.

18. The computer-readable medium of claim 11, wherein activating the flow control processor includes:

setting a “Initial Cell Rate (ICR) Constant” attribute to zero;

loading one or more rate profile tables;

setting a “Resource Management (RM) cell interval” attribute to 100 milliseconds; and

setting an “Idle Virtual Circuit Factor” attribute to eight (8).

19. A method for setting flow control attributes in an ATM network, the process comprising:

locating an eligible user network interface (UNI);

setting flow control attributes of trunks connected between the UNI and an ATM switch to predetermined values;

activating a flow control processor for the eligible UNI; and

setting flow control values to a final setting based at least in part on information received from the flow control processor.

20. The method of claim 19, wherein the flow control values facilitate management and control of traffic flow in the ATM network by ensuring fair traffic balancing between virtual circuits and virtual paths in the ATM network.

21. The method of claim 19, further comprising repeating said process for a plurality of UNIs.

22. The method of claim 19, wherein the predetermined values are used during the set up of the UNI.

23. The method of claim 19, wherein an eligible UNI is any UNI connection on an ATM switch in which the flow control processor is required to be activated.

24. The method of claim 20, wherein the final flow control values for a UNI setting comprise at least one of setting a “Generation” element to “No Loop” and setting a “Termination” element to “CCRM and Backward Control Management”.

25. The method of claim 20, wherein the final flow control values for an RM-cell setting comprise at least one of setting a “Generation” element to “Call Control Resource management (CCRM)” and a “Termination” element to “CCRM”

26. The method of claim 19, wherein activating the flow control processor includes:

setting a “Initial Cell Rate (ICR) Constant” attribute to zero;

loading one or more rate profile tables;

setting an “Idle Virtual Circuit Factor” attribute to eight (8).