Blueprint: Network Architecture

Network Planning and Forecasting � Past, Present and Future

by Ross Munro and Mark Mortensen,

3/10/2008

The networks of yesterday were dominated by voice and low-bandwidth data services, such as e-mail and basic Internet connectivity. They have been planned in the same way for the last one hundred years, with the marketing organization and the planning organization working together in a time-honored dance.

The Old Model -- Incremental Planning Built on Historical Trends

The first step in determining the capital required to build a network that was mapped to available budget and expected service demand, was simple in structure, as shown in Figure 1.

Network usage data was traditionally gathered by the planning organization from the as-built network and analyzed using trending methods, then modified by forecast information from marketing to reflect that organization's changing demands.

The planning organization would use this information to decide which new equipment would be necessary to meet demands, often eschewing the marketing input (i.e. "They incorrectly predicted a large uptake of ISDN once, why should we believe them now?"), and effectively over-built the networks to consume the available budget.

This practice cost more, but assured that resources were available to meet customer demand and, even if the marketing organization was right and the new service was a hit, would require but a small incremental increase in capacity to get by.

Such high-cost planning methods were tenable when:

The services provided changed little year to year
The rate of service adoption was relatively stable
Consumers had little choice in substitute technologies

Of course, even with this relatively simple method, a Tier 1 carrier could find itself with as many as 15,000 separate construction projects per year as capacity was added where needed and reduced where not needed, and new technologies were introduced into the network.

The New Model: Market-Driven Planning

Fast-forward to the present day. Carriers' marketing, technology and business departments must work together more effectively in the planning stages to ensure success when introducing new technologies, business models, and services.

Standard forecasting and data trending was sufficient for planning yesterday's networks, but is no longer adequate for introducing next generation network architectures, or new bandwidth-hungry services, as there is no historical data to use for trending purposes. Overall market take rates are unknown, and very difficult to break down across multiple serving territories. And with the large bandwidth demands of video customers, it is not economically feasible to simply "over-provision" the network -- yet if a mistake is made and the network is under-built, the quality of service will suffer severely, crippling the market introduction of the new service.

This lack of data means the carrier must derive its master plan proactively from market information, as opposed to historical network information, as shown in Figure 2. Here, the marketing organization must determine the anticipated demand for services and make it available to the network planning organization to create a strategic network plan. Then, since the market demands are probabilistic, they must be checked occasionally -- much more often than yearly, as was done in the past -- and the plans changed as more information is accumulated about actual market demands, values and locations. The trending information, thus, takes a back seat to the market demand data in driving the plans -- trending becomes a "check" on the plan, and, in some cases, a fine tuning of the network plan.

Network Resource Planning is the name give to this "new" model of planning -- being driven primarily by marketing information. It incorporates a combination of business process standardization, IT data and applications.

When implemented, NRP enables carriers to more easily and quickly determine in specific detail what resources are required to support market demand in each geography. It also works in alignment with the carrier's business planning cycles, to determine the type of traffic, QoS requirements and the underlying equipment required by each service in its planning.

Lastly, NRP allows planners to work more easily with financial and logistics teams to order the right equipment at the right time, and with the operations team on the physical layout of the network additions, organized by project.

How does NRP work? First, it calculates a total projection of required resources by looking at the network capacity required to fulfill the demands. Then, the existing and work-in-progress network resources are subtracted from the planning equation. What remains is the additional required network capacity per service, per geography, per network domain and per technology, the requirements for a next generation network build-out and any planned legacy network decommissioning.

This approach to planning new or evolving networks takes maximum advantage of the data available from carrier OSSs that hold network knowledge (i.e. inventory and performance data), which is used to assemble a view of the current network and near-term planned network capacity additions and subtractions, as shown in Figure 3.

Planners then perform additional what-if analyses to determine the network's resilience to overload and disaster conditions, and add in contingency network capacity as dictated by business policy.

Furthermore, IP networks are prone to dropping or delaying packets when they are overloaded, causing digital "jitter" and delays that severely impact the quality of experience in services like voice, two-way video and gaming. As such, additional studies, often involving "simulation" of the network under various load conditions, may be performed. By doing this, network planners can understand how services will be affected under varying network conditions and modify the network plans to prevent these complications, as well as determine how the network can be configured to provide the best service at the lowest cost.

The issue is further compounded by the way network layers interact. For example, new services will ride on the IP and/or Ethernet network, and high-QoS services will use special high-reliability routes, but all of this traffic rides on the same underlying logical transport network--ring or mesh--which in turn rides on the same underlying optical infrastructure. The effect of traffic on each layer must be taken into account when planning, making reliability and disaster scenarios especially complex. Planners must ensure that backup resources are available at each layer, and that no backup paths are routed on the same physical optical facilities.

Network Resource Planning & Management Process

Planning for network changes are typically handled in two steps: strategic and tactical, both utilizing the information and techniques previously described. These steps then feed into the operations process for implementing network changes, and other ongoing operations that consume the resources as services are added.

Network Resource Planning -- Strategic

Strategic Network Resource Planning is done usually one and two years in advance, answering the basic question "How might we change the network, and how much might it cost?" The process looks at the resources required beyond the current operating cycle, making use of "what if" analyses that allow carriers to:

Issue design guidelines to the rest of the planning organization for implementation of new technologies -- these will later be "baked into" the network implementation plans (and into the planning systems used)
Determine the technologies to be deployed and the vendors to be selected
Make recommendations to the downstream groups on resources to be provisioned, and where and when the capacity should be available, entered into the Enterprise Resource Planning (ERP) system for negotiation and equipment ordering
Give the finance organization an estimate of the capital and expense budget impacts of the capacity additions and network transformations
Organize network planning into a single, comprehensive network plan for all of the technology layers
Update the network plan during the year as more information on market take rates and new services becomes available

Since budgets and specific vendor choices are never completely known ahead of time, and the priorities of the various network changes are never completely stable, many further "what if" analyses are often necessary within a short period of time, placing considerable strain on the planning group, who must repeat this process, incurring the same cycle times for each successive iteration. But since these cycle times typically require three to six months, the "what if" analyses are limited.

By contrast, NRP enables extensive "what if" analyses by automating many of the planning tasks, and enforcing standardized, repeatable business planning. The benefit is clear: optimal network plans, aligned to network demands.

Network Resource Planning -- Tactical

Tactical Network Resource Planning is done usually six months before implementation, answering the basic question "How will we change the network, and how much of what equipment do we need to order?" At the tactical stage, planners validate the recommendations received from their strategic planners, using updated forecasting and network usage data, along with more detailed knowledge of local conditions and updated budgets. This output is then used to:

Create and schedule work projects for network capacity additions, rearrangements, or decommissioning
Order equipment
Provide a first cut at the layout of the equipment for the work projects

Network Resource Management & Operation

The resource planning process is now complete -- the logistics process ensures that the right equipment is available at the right time, the engineering organization plans out the work projects and initiates and monitors their completion, and the network resources are turned over to operations for consumption in delivering services.

NRP remains involved to help implement large private networks and to advise on the necessary equipment changes required to properly respond to shifting network demands.

The New Breed -- Integrated Network Resource Planning Systems

To date, the myriad of available planning tools -- some home-grown, some commercial - have been specialized and disparate (e.g. by technology, layer or domain).

A new breed of Network Resource Planning Systems has emerged that integrates these tools into a single comprehensive network planning system powerhouse. These systems provide:

An overall plan of the network at various stages of its evolution for each of the technologies, ensuring consistency among layers
Advanced optimization algorithms for efficient demand routing across the network, ensuring the least capital requirements and proper quality of service
A standardized work flow for planning that unites disparate planners and stakeholder groups on a common platform;
Deep knowledge of the interconnections among layers, ensuring that contingency equipment is coherently deployed across the network layers
The ability to create a plan in hours or days, instead of weeks or months, allowing faster response to changing conditions, as well as greater opportunities for "what-if" analyses to determine optimal strategies

Leading communications service providers worldwide are now in the process of deploying these new Network Resource Planning systems. Some, like BT, are using them to plan complete network transformations, while others, like Telstra, are augmenting their current networks with new technologies and incrementally migrating to their next generation architecture.

The Future of NRP Systems

NRP systems are in the nascent stage, although they are developing rapidly and already providing real-world benefits. In the future, new features will be introduced, such as:

Process automation to radically shorten the planning cycle from several months to a few days, or -- even further - decrease the number of planners and provide them with ever more powerful tools
Integration with the ERP logistics process to bring Just-In-Time principles to the network capacity augmentation process - for automating equipment ordering and determining its best use, given the current situation,
More detailed automated network design, reducing the network engineers' workload

With NRP systems, the network of the future will be planned more quickly, with less effort and be more efficient.

About the Authors

Dr. Mark H. Mortensen, President, Mortensen Consulting Group

Dr. Mark Mortensen has been on a 25-year quest, while serving as a product management and marketing executive at Bell Labs, Granite Systems, Telcordia, and VPIsystems, to transform the operations of service providers for the next generation of services through the use of advanced communications software. He currently is advising vendors on product directions and M&A, carriers on OSS architecture, and private equity and venture capital organizations on investments. Mark holds a PhD in physics from Yale University.

Ross Munro, Business and Operations Support, VPIsystems

Ross Munro has been a telecommunications professional for over 30 years and currently serves as Business and Operations Support at VPIsystems. During his previous career at Bell Canada and its subsidiaries, he worked on all aspects of network planning and engineering, with noteworthy achievements in R&D Management and Operations Solutions, including the launch of Bell's Network Inventory Management transformation program in 2002. He is also the founder of Comscient Consulting Services, bringing the benefits of his real-world experience to carriers and software vendors as they seek to create new ways of planning and implementing modern networks. He has a BASc in Engineering from the University Of Waterloo, and an MBA from the University Of Toronto.

About VPIsystems

VPIsystems is the only provider of integrated capacity and network planning software and services for the global telecommunications industry. The company's OnePlan^TM software system gives telecommunications and multi-service providers the ability to cohesively plan the financial, technical and marketing aspects of their network evolution, for all current and future network types. Headquartered in Holmdel, NJ, and with offices in Europe, Asia, and Australia, VPIsystems' software is used by over 150 communications service providers and network equipment manufacturers to assess current and future capacity needs, and optimally plan their QoS-constrained service networks and underlying transport infrastructure.

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