Download Operation Support System and more Lecture notes Computer Science in PDF only on Docsity!
Operations Support Systems (OSSs)
Definition
The term operations support systems (OSSs) generally refers to the systems that perform management, inventory, engineering, planning, and repair functions for telecommunications service networks.
Overview
Originally, OSSs were mainframe-based, stand-alone systems designed to support telephone company staff members in their daily jobs. Essentially, these systems were designed to make the manual processes through which a telephone network was operated more efficient. Today's service providers, however, are required to manage a much more complex set of services and network technologies in order to remain competitive. As a result, new generations of OSSs are being developed—using state-of-the-art information technology—to address enterprise data information management. These systems make a company's information a more accessible and useful resource for managing the business, providing services, and delivering extraordinary customer care. This tutorial focuses on the current and near- future states of OSS technology and its development to support emerging and hybrid network technologies. Note that the tutorial focuses only on the service- management layer of the telecommunications management network (TMN) model. Refer to the Web ProForum TMN tutorial for a complete discussion of this model.
Topics
- The Basics of OSSs
- OSS Interconnection
- Operations Support of Data Services
- Business Impact of an OSS Solution
- Conclusion Self- Test
Web ProForum Tutorials Copyright © 2/
Correct Answers Glossary
1. The Basics of OSSs
The easiest place to start a discussion of OSSs is with the fundamental systems in the ordering process for any-voice services provider. The process flow from placing an order for service to activating that service on the network leads through workflow, ordering, inventory, circuit design/engineering, provisioning, and activation systems.
Figure 1. Process Flow
Workflow Engine
A workflow engine is generally at the heart of an integrated OSS infrastructure. It can be built in any number of configurations utilizing any number of technologies, but its purpose is generally the same regardless. The workflow engine manages the flow of information from system to system, essentially checking off the tasks associated with any process as it goes. Some OSS vendors package workflow engines with their systems whereas other vendors specialize in
Web ProForum Tutorials Copyright © 4/
equipment and network routes a given service will utilize. For example, if T service is requested, channels, ports, cards, and circuits must be assigned on any combination of M13 multiplexers, digital cross-connect systems, T3 facility circuits, or synchronous optical network (SONET) channels and network routes connecting carrier network locations to the end user. Network locations are identified by a Telcordia Technologies (formerly Bellcore) standard, eight- or eleven-digit common language location identifier (CLLI) codes. For example, a CLLI code of PLANTXXAH01 would indicate a SONET shelf at the "A" designated end office located in Plano, Texas. Similarly, exchange carrier circuit identification (ECCKT) codes identify specific circuits.
Figure 2. CLLI Code
A current trend for design-and-assign systems is to incorporate graphical tools that allow a system user to create services on a network map with point-and-click capability rather than either drawing maps by hand or relying on an abstract set of equipment identifiers displayed in a table.
Element Management and Activation and Field
Service Management
Once the previous tasks are accomplished, service can be activated on the network. Activation requires several steps. If new equipment or lines must be installed, or if equipment or lines must be configured manually, a field service– management system must be notified so that technicians can be dispatched. Field
Web ProForum Tutorials Copyright © 5/
service systems must not only notify technicians of the service being installed but also of the specific equipment involved and where it is located. For example, services provided to a large office complex must be associated with a building, floor, network, closet, and perhaps a certain equipment rack within that closet.
Some activation can be performed automatically. Today's service providers are working toward enabling flow-through provisioning and activation, combining provisioning and activation systems to allow order and design-and-assign systems to issue commands to an activation system. The activation system then automatically activates service on the proper network elements (any piece of network hardware, such as a switch, multiplexer, or cross-connect system).
Current network elements are generally designed with an intelligent element manager built in that can receive and execute commands sent by activation systems. Element managers also can feed equipment status data back to upstream systems for network- and trouble-management functions. Element managers use protocols such as common management information protocol (CMIP), transaction language 1 (TL1), or simple network management protocol (SNMP) for traditional data equipment to communicate with activation and other systems. An activation system often acts as a manager of managers, overseeing and communicating with a number of various element managers and equipment types.
Figure 3. Manager of Managers
Web ProForum Tutorials Copyright © 7/
customer databases and various OSS functions, such as preordering, ordering, and provisioning. (Preordering is the process by which a competitive local- exchange carrier [CLEC], with permission from the customer, requests data regarding that customer from an RBOC.) The Federal Communications Commission (FCC) has made it clear that RBOCs will not be permitted to enter the long-distance business until, among other things, they create access mechanisms that both state regulatory commissions and the FCC deem sufficient to enable competition. RBOCs and incumbent local-exchange carriers (ILECs) have built or are building interfaces into which a CLEC can connect its systems. This is an extremely difficult and time-intensive task, one with which the industry has wrestled for several years. In the meantime, carriers often rely on manual means, such as phone calls and faxes, to exchange customer data and service orders. Manual processes are highly error-prone and slow—insufficient for a truly competitive environment.
Interconnection Challenges
The first problem RBOCs face in enabling interconnection is integrating their own OSSs. A large number of RBOC OSSs are stand-alone mainframe systems that were never intended to be integrated or accessed by anyone but the RBOCs. Often referred to as legacy systems, they were designed to assist people in their daily jobs. Most RBOCs are conglomerations of many smaller local phone providers and are still in the process of consolidating, integrating, and eliminating their legacy systems. These systems cannot be easily replaced, however, due to both the cost and time involved in such a large-scale project and the fact that these systems are critical to everyday RBOC business processes. RBOCs are working steadily, though the process is innately slow, to replace their older systems with modern, integrated OSS packages.
Web ProForum Tutorials Copyright © 8/
Figure 5. RBOC Legacy Environment
RBOC legacy systems do not have sufficient security mechanisms to partition customer data—in other words, to keep RBOC customer data separate from CLEC customer data. Additionally, external interfaces must be added on to these systems to allow integration with surrounding systems. Without such integration, functions such as flow-through provisioning are impossible to enable. These systems also must be able to respond to commands coming from an interconnection gateway in order to fulfill CLEC data requests.
There are many conceptual and technological approaches to legacy systems integration. These approaches involve technologies such as middleware, transaction processors (TPs), workflow systems, and object engines. Middleware is a term commonly applied to any integration technology, and it is often used interchangeably with TP. These technologies present a common application programming interface (API) into which a system can be integrated to manage data translation and exchange among disparate systems. Workflow systems often work hand in hand with TPs, providing multiple, dynamic APIs and managing data flow and task sequencing while the TP handles data conversion. Object engines use technologies such as the Object Management Group's (OMG) common object request broker architecture (CORBA) or Microsoft's distributed component object model (D–COM). Object engines abstract application interfaces into definable, flexible software objects that allow applications to communicate in a uniform manner through the engine itself.
Web ProForum Tutorials Copyright © 10/
A gateway's primary function, as mentioned above, is to manage the interfaces between CLEC and RBOC OSSs. Gateways handle data integrity and security between carriers as critical customer and service data is exchanged. One of the most important aspects of a gateway, however, is to perform error checking on service orders as they are passed across carrier boundaries. With manual processes, a CLEC often sends service orders to an ILEC or RBOC that end up lost in a pile of faxes for several days. When orders are finally attended to, they are rejected if they are incomplete or somehow erroneous—a common occurrence because orders can be rejected for simple typographical errors. They are only then returned to the CLEC for reprocessing. This adds days and even weeks to the ordering process. A gateway can reduce these errors by reviewing all orders before submission to the ILEC, returning any erroneous orders for instant review.
Another critical function of a gateway is to facilitate the preordering process. In this process, the CLEC secures permission from a potential customer to obtain its data from the ILEC. This data consists of a customer profile, outlining all the service provided to the customer. This data is often transferred in the form of universal service order codes (USOC). These codes are cryptic, and there are thousands of them. In a manual process, a CLEC customer representative must flip through a large catalog to determine the services provided and to build sales quotes for similar offerings. Again, this is an extremely time-intensive process. New gateway software can read these codes and match them to a CLEC's product catalog database to automatically generate product offerings and sales quotes, making the CLEC customer-acquisition process far more efficient.
Figure 7. Interconnection Process
Web ProForum Tutorials Copyright © 11/
3. Operations Support of Data Services
As complex as the OSS infrastructure for a wireline network is today, it will only become more complex as new network technologies are introduced to the carrier environment. Packet technologies, such as Internet protocol (IP), frame relay (FR), and asynchronous transfer mode (ATM), are becoming increasingly prevalent in the public network. While service providers have been managing FR and ATM for several years, the demand for more feature-rich services has necessitated reworking OSSs to support the complexities of service-level- agreement (SLA) management, usage-based billing, and flexible quality-of- service (QoS) parameters.
IP, the technology that drives the Internet, is developing into a carrier-grade technology that will enable a mix of voice and data services to be more advanced and widely available than has ever been possible before. Like ATM and FR, IP services are demanding support to ensure high QoS. Two major hurdles must be overcome to meet that goal. First, service providers must adopt QoS that can map to both connection-oriented and connectionless protocols. They also must address the integration of an IP−address management system.
Data Service Provisioning
Assuming a service-management perspective for offering data services, the service provider defines the bandwidth access circuits for the A and Z locations and the bandwidth for the QoS, service category parameters, or both as they relate to the particular permanent virtual circuit (PVC). After provisioning the equipment, the provider defines a virtual layout for the field to use for the actual mapping of the virtual circuit (VC) to the equipment.
Web ProForum Tutorials Copyright © 13/
permit simultaneous voice and data streams to travel over the same wire pair. Having accurate records of their copper infrastructure is a major concern for incumbent service providers. Service providers that are Internet service providers (ISPs) or CLECs also have major concerns about getting access to unbundled loops and a clear communication path to the incumbent provider.
A central office (CO) must incorporate two new components to enable xDSL technologies: a splitter and a digital subscriber line access multiplexer (DSLAM). The splitter simply distributes the voice traffic to the POTS network and the data traffic to the DSLAM; it is expected that the splitter will largely become obsolete as the demand for an all-in-one box increases. The DSLAM communicates with the xDSL modems installed at the end-user location and aggregates multiple xDSL streams into a switch for transport on high-capacity circuits using various multiplexing schemes. It is managed and maintained much like other end-office equipment, but most installed OSSs do not yet support the technology. xDSL modules must be added to older OSS systems to enable automatic provisioning and management of xDSL services. The splitter simply distributes the voice traffic to the POTS network and the data traffic to the DSLAM.
The new xDSL technology has several core functions that the existing OSS should support. For example, the DSLAM and splitter, while specific to xDSL technologies, are very similar to a service provider's existing equipment (i.e., routers and switches) in terms of equipment inventory. Supporting customer premises equipment (CPE), on the other hand, may be a new challenge for the service provider. However, providers with a managed service offering may find they also can handle the CPE network aspects.
The more complex scenarios for broadband access involve incorporating VCs along with voice services. OSSs traditionally have not viewed an xDSL as capable of providing this type of service. One approach is to handle the cable pair as a channelized T1 circuit capable of handling both voice and data circuits. The scenarios typically encountered range from only offering xDSL on the cable pair, with no voice service, to offering a small office with multiple users an xDSL solution involving voice channels as well as several VCs that each have differing levels of service (such as an analog phone, a PVC for Internet access, a PVC to corporate headquarters, and an Internet phone connection).
Web ProForum Tutorials Copyright © 14/
Figure 9. DSLAM
One of the problems with xDSL technologies is that they are susceptible to a number of network pitfalls. For example, local loops that are equipped with special noise filters or load coils will filter out the frequencies at which xDSLs operate, rendering them ineffective. Additionally, some services can create interference on xDSLs. If an xDSL loop rides in the same bundle as a loop delivering one of these services, the xDSL service can be disturbed. Also, some older copper wires, installed years ago, are simply insufficient to support the service. Some RBOC regions lack detailed line records that can inform service providers of potential problems because line records are kept on spreadsheets or even by hand and are not updated accurately. A strong network-inventory system is thus critical to the effective deployment of xDSL services.
4. Business Impact of an OSS solution
Service providers are constantly striving to differentiate their businesses from those of their competitors through superior customer service and rapid time-to- market for new products and services. A powerful OSS solution can help service providers meet these goals while controlling their operating costs.
Quality of Service
In its simplest terms, QoS is a measure of the telephone service quality provided to a subscriber. This measurement can be very subjective, and the ability to define it depends upon the technology being used. For example, ATM and FR technologies were designed with multiple grades of service delivery in mind, but
Web ProForum Tutorials Copyright © 16/
architecture that supports both current and new technologies, enabling service providers to respond immediately to business changes, whether these changes stem from marketing decisions, new technologies, or regulatory requirements.
5. Conclusion
Ideally, an OSS's architecture enables work to flow electronically across the organization, providing visibility to the processes and resource utilization. It also should enable the service provider to manage the end-to-end service delivery process that often involves more than one type of order or transaction across the organization, as well as with other service or network providers. Most important, this software should be available in a single solution, eliminating the complexity of dealing with a variety of systems. If a service provider cannot achieve this goal due to complex OSS requirements, the provider should carefully select best-of- breed vendors offering proven, integrated solutions.
Self-Test
- Which of the following is a function of a workflow engine?
a. to provide network repair information for field service technicians
b. to prompt customer-care representatives to sell specific service packages
c. to facilitate communication and task sequencing among various OSSs
d. to draw graphical network maps for capacity planning
- A CLLI code is a Telcordia Technologies (formerly Bellcore) standard code used for _____________.
a. identifying specific circuit paths
b. identifying network locations
c. identifying a customer's long-distance carrier
d. transmitting fiber-optic signals
- Which of the following is not a protocol used for communicating with network elements?
a. CMIP
b. SNMP
Web ProForum Tutorials Copyright © 17/
c. TL
d. TMN
- All network elements are equipped with built-in intelligence that will reroute network traffic around trouble spots.
a. true
b. false
- Legacy systems are ________.
a. systems created from parts of other systems
b. any RBOC OSS
c. older, stand-alone mainframe systems common to ILECs
d. systems used to interconnect LEC OSSs
- OSS interconnection is mandated and a critical factor in determining ILEC entry into long-distance markets.
a. true
b. false
- Interconnection gateways often perform error-checking functions to help speed the ordering process.
a. true
b. false
- Which of the following is not an inhibitor to DSL deployment?
a. DSLAMs cannot be housed with circuit switches.
b. Some lines carry load coils and filters that can negate DSLs.
c. LEC line records are often inaccurate.
d. Services riding adjacent lines can interfere with DSLs.
- IP guarantees time and delivery sequence for all packets on a network.
a. true
Web ProForum Tutorials Copyright © 19/
b. SNMP
c. TL
d. TMN
See Topic 1.
- All network elements are equipped with built-in intelligence that will reroute network traffic around trouble spots.
a. true
b. false
See Topic 1.
- Legacy systems are ________.
a. systems created from parts of other systems
b. any RBOC OSS
c. older, stand-alone mainframe systems common to ILECs
d. systems used to interconnect LEC OSSs
See Topic 2.
- OSS interconnection is mandated and a critical factor in determining ILEC entry into long-distance markets.
a. true
b. false
See Topic 2.
- Interconnection gateways often perform error-checking functions to help speed the ordering process.
a. true
b. false
See Topic 2.
Web ProForum Tutorials Copyright © 20/
- Which of the following is not an inhibitor to DSL deployment?
a. DSLAMs cannot be housed with circuit switches.
b. Some lines carry load coils and filters that can negate DSLs.
c. LEC line records are often inaccurate.
d. Services riding adjacent lines can interfere with DSLs.
See Topic 3.
- IP guarantees time and delivery sequence for all packets on a network.
a. true
b. false
See Topic 4.
- Data warehousing provides quick and easy access to performance metrics.
a. true
b. false
See Topic 4.
- If Mickey is a mouse and Donald is a duck, what is Goofy?
a. a dog
b. a dawg
Glossary
ADSL
asynchronous digital subscriber line; current technology that enables digital, high-capacity, and simultaneous voice and data transmission over copper local loops; called asynchronous because it utilizes a higher-capacity channel going to the user than coming from the user
analog modem a device designed to transmit and receive signals over regular telephone lines, most common method for accessing the Internet today
