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Cisco Broadband Access CNSP

Subscriber Edge Provisioning in Data and Voice Convergent Networks

White Paper

Subscriber Edge Provisioning
in Data and Voice
Convergent Networks

Introduction

The Cisco Convergent Network Solutions Center Subscriber Provisioning (CNSC SP) application addresses the challenges that face many service providers by automating the manual steps of provisioning customer premises equipment (CPEs) and aggregation devices of the last-mile connectivity for IP data networks and voice-over-IP (VoIP) deployment. Cisco CNSC SP helps to accelerate time to market for new data and VoIP service rollout with its unique facilities to customize service offerings.

Provisioning of subscriber edge for multi-services in convergent networks requires the configuration of CPE devices, access devices, and network resources like IP address management. In addition, the required operation sequences and configurations vary depending on the network technologies and the services being offered. It is a huge challenge for the service providers to support new services without network management tools. Today the provisioning process is generally performed manually, and it is very tedious, labor intensive and error prone. In addition, this process prolongs significantly the service activation time. To compete for market share and increase profitability, service providers must build systems that reduce administrative costs and accommodate rapid and scalable subscriber growth. Therefore, there is a high demand for the automation of the provisioning process, and minimum manual interventions to turn on services.

Function Overview

Cisco CNSC SP provides a topology view of the subscriber access edge network, with displays of the customizable logical partition of the network, the network elements (for example, CPEs and aggregation devices), and data related to provisioning.

The following figure shows a generic Packet Telephony architecture framework, where Cisco CNSC SP can be deployed at the network management layer for subscriber edge provisioning.


Figure 1: Network Management Layer


Highlights of Cisco CNSC SP 2.0 features include:

  • Flexible voice and data service provisioning—Provides CPE and aggregation device configuration for service activation, modification, and deletion for voice and data services

    • Allows incrementally adding, modifying, or deleting services based on customer (subscriber) needs

    • Allows customization of the configuration of CPE/aggregation device through templates

    • Allows the creation of new service offerings, and customization of the provision flow for activating/modifying/deleting such service offerings

  • Multiple network technology supported

  The Cisco CNSC SP framework is independent of network technologies. The framework supports multiple access methods, CPE/aggregation devices, and CPE configuration delivery methods. The current release supports subscriber-edge provisioning in Media/Simple Gateway Control Protocol (MGCP/SGCP) VoIP and data IP networks:
  • ATM core with digital-subscriber-line (DSL) access, Cisco 827 DSL CPE provisioning based on stage (Telnet) or auto-provisioning using Open DSL (FTP for file download)

  • ATM core with T1 access, Cisco 2421/3810/3660 T1 CPE provisioning based on stage (Telnet)

  • IP core with T1 access, Cisco 2421 T1 CPE and Cisco ESR 10000 Edge Services Router aggregator provisioning, CPE provisioning based on stage (Telnet) or auto-provisioning based on IE2100 (HTTP for file download)

  • Subscriber network inventory and administration—Supports the partition of a network into provisioning domains, based on CPE aggregation and access technology in the service provider's network; maintains a repository of inventory data (based on manual input) related to subscriber CPE provisioning

  • Resource management—Provides IP address pool management and IP address allocation; tracks and manages T1 port usage on aggregation router (for VoIP-over-PPP-over-T1 solution)

  • Template-based Cisco IOS device configuration for easy customization

  • Operation, Administration, and Maintenance (OA&M) —Provides operator login/authentication, audit-trail logs for service request and system management functions

  • Graphical user interface (GUI) for subscriber network inventory, administration, and provisioning

  • OSS application programming interface (API) Common Object Request Broker Architecture Interface Definition Language (CORBA IDL) for OSS integration and flow-through service provisioning

  • Scalability and performance—Scale to handle high-end networks with large numbers of CPEs; support multiple operators for simultaneous access

Cisco CNSC SP performs the following tasks to fulfill a service request:

1. Takes a service request from OSS or service-provider operator

2. Decomposes the service request into a sequence of tasks

3. Executes the tasks that configure a CPE, aggregation device, and related network elements (for example, a Remote Access Dial-In User Service [RADIUS] server) for the desired services; this is achieved by:

  • Collecting configuration parameters (including resource allocation/de-allocation for IP addresses, T1 ports on the aggregator device)

  • Generating configurations, based on templates defined for the service and CPE/aggregation device type

  • Delivering the configuration to the CPE, the aggregation device; configuring the RADIUS server (optional) with user profile for CPE authentication

The configuration delivery method for a CPE depends on the auto-provisioning mechanism supported by the CPE. Examples of a configuration delivery method include Trivial File Transfer Protocol (TFTP) download (Dynamic Host Configuration Protocol [DHCP] based), Hypertext Transfer Protocol (HTTP) download (from a web server), or performing a Telnet to CPE to download a configuration. Cisco CNSC participates in the delivery process either by preparing and storing the configuration file for access by the CPE, or directly sending the configuration down to the CPE.

  • Listening for event/notification from the CPE on the status of the configuration download (if supported by CPE)

4. Notifies OSS/service-provider operator of the status

Cisco CNSC SP application relies on the following components to provide its full functions:

  • Cisco Network Registrar (CNR, including both DHCP and Domain Name System [DNS]); optional: provides IP address management and fully qualified domain name (FQDN) (DNS domain name) update functions

  • Cisco Intelligence Engine 2100 (IE2100)—Provides regional configuration file delivery functions (HTTP file download for Cisco IOS® device)

Cisco Access Registrar (AR) (RADIUS server)—(optional) Provides CPE authentication functions for Point-to-Point Protocol [PPP] session authentication.

Operation Flow

Cisco CNSC SP supports three types of protocol on CPE initial configuration:

  • Open DSL for the Cisco DSL CPE

  • A Cisco IE2100-based plug-and-play for Cisco IOS-based CPE

  • Telnet via console port, for all the CPEs

Ongoing configuration can be done via Open DSL, IE2100, or Telnet.

Service Provisioning

Approach

In order to provision a CPE in a convergent network, Cisco CNSC SP needs to solve two major issues:

1. It needs to translate a service request into the procedures for CPE provisioning. The procedures define the steps to gather CPE configuration parameters generate configurations and configure the CPE and aggregator devices to fulfill a service request. This translation is achieved by using a data-driven approach. Cisco CNSC SP defines a service profile to specify a service provider's packaging of services to be offered. The service profile can be implemented by multiple technologies, which are defined in the provision profile. A provision profile specifies the technology, the network elements, the configuration templates, and the delivery methods to provision a service described in the service provision profile. Finally, a task profile needs to be defined to specify the sequence of tasks to complete the service request.

2. Some tasks need to map a service request into the specific configuration commands, in the format of a device configuration file. This is achieved using the template approach. A template file defines the configuration for activating, modifying, or deleting a service or service feature on the device. The template file contains variables that are service related and specific to each device; for example, IP address for voice signaling channel, quality-of-service (QoS) parameters for different classes of services, and so on. The values of these variables are either generated by Cisco CNSC SP (for example, IP address) or derived from a service request. A template file may also contain non-service-related variables (for example, SNMP-trap destination IP address) that are required for device configuration. The values (template data) of these variables need to be specified by OSS applications/operator as additional input to Cisco CNSC SP in a service request.

Figure 2 shows the relationship among the service profile, provision profile, and task profile:


Figure 2: Service, Provision, and Task Profiles


  • Service profile—Defines the service package to be provisioned for a CPE in the service-provider network.

  The service profile is technology neutral; it describes only the service offering, not the technology to be used to implement the service. Different types of technologies, which are described below, may implement a service. A service profile consists of:
  • Service type—Defines the type of service; for example, voice gold, voice, and data primitive

  • Class of service—Identifies the class of service, such as platinum, gold, bronze

  • Service features and parameters—Describes features of the service offering and related QoS parameters, such as voice call features (call waiting, three-way conference call, caller ID, and so on), data features (PPP, Network/Port Address Translation [NAT/PAT], DHCP, connection speed 56K, e-mail account with 1-MB storage, and so on). Service features are orderable units, and can be provisioned incrementally.

  • Provision profile—Defines the technology used to implement a service profile, and the configuration templates and delivery methods for adding/modifying/deleting a service as defined in the service profile.

  A provision profile consists of:
  • Technology type, for example, VoIP, PPPoT1, VoIPoATM, DSL

  • A list of:

- Device type, model
- Configuration template files associated with each service type or feature, for each operation
- Default template data—Specifies default values of user-defined template variables
- Configuration delivery method—Specifies the default configuration delivery method (for example, Telnet, IE2100)
  • Task profile for adding/deleting/modifying service

  • Task profile—Defines the operation sequences (flow) to be executed to fulfill a service request (add, modify, or delete service). Task profile is defined using a simple scripting language (referred to as task definition language) and primitives.

    • Task primitive—Defines a unit of work as a decomposed network operation, such as reserve_ip, generate_config, create_voice_channel; Task primitives are predefined by Cisco CNSC SP and are not customizable

A sample task profile for adding a voice service may consist of the following steps:

  • Allocate or de-allocate IP address in DHCP (depending on the network technology, one or multiple IP addresses are required), and update DNS with IP address, Fully Qualified Domain Name (FQDN) mapping

  • Configure RADIUS server with user profile for CPE authentication

  • Generate configuration file for the aggregation device (for example, Cisco ESR10000), using the template specified in the provisioning profile, with the configuration parameters generated by Cisco CNSC SP (for example, IP addresses) and from the service request

  • Deliver the configuration file to the aggregation device, using the delivery method specified in the provision profile

  • Generate configuration file for the CPE, using the template specified in the provisioning profile, with the configuration parameters generated by Cisco CNSC SP (for example, IP addresses) and from the service request

  • Deliver the configuration file to Cisco IE2100 for CPE to download (HTTP based)

Cisco CNSC SP provides pre-defined profiles for basic voice and data provisioning. Service providers may also create customized profiles to offer branded voice and data services.

Conclusion

Cisco CNSC helps to eliminate one of the major challenges to scalable edge device network service management for VoIP with a product the works out of the box via easy to use GUI and an OSS APIs for flow through automated operations to speed delivery of VoIP services while reducing the associated network management cost. In summary, Cisco CNSC SP is a carrier-class service and network management system that provides the following major benefits:

  • Offers simplified data service and network management

  • Provides simplified voice service and network management

  • Offers OSS API for flow-through OSS operation

  • Enables rapid rollout of new services

  • Offers improved time to market

  • Provides improved network quality

  • Reduces operational cost

  • Reduces total cost of ownership

  • Enables service providers to focus on core business

Definitions

Cisco CNSC—Cisco Convergent Network Solutions Center

CPE—Customer premises equipment

CNR—Cisco Network Registrar; consists of DHCP and DNS

CNS—Cisco Network Services

Configuration—Basic device configuration; refers to the activity of generating configuration file (template based), downloading, and applying the configuration to device

DNS—Domain Name System; used for IP address lookup based on domain name

DHCP—Dynamic Host Configuration Protocol (RFC 2131); DHCP clients obtain their IP address assignments and other configuration information from DHCP server

DSL—Digital Subscriber Line

FQDN—Fully qualified domain name

HTTP—Hyper Text Transfer Protocol

IE2100—Intelligent Engine 2100, Cisco appliance to facilitate CPE auto provisioning and configuration file delivery.

OSS—Operations Support System; used by service provider

PPP—Point-to-Point Protocol; used for establishing a point-to-point link that provides a single, preestablished WAN communications path from the customer premises, through a carrier network (the telephone company), to a remote network

Provisioning—Subscriber CPE provisioning; refers to the activity of allocating resources (IP address, FQDN), generating configure file, downloading, and applying the configuration to device

QoS—Quality of service

RADIUS—Remote Access Dial In User Service

MGCP—Media Gateway Control Protocol

SGCP—Signaling Gateway Control Protocol

(T)FTP—(Trivial) File Transfer Protocol

VoIP—Voice Over IP (Internet Protocol)