Network Design Process – Effective Network Planning and Design

Overview

The network planning and design methodology describes a process with 9 specific steps and a sequence for those activities. As mentioned it is an engineering life cycle that supports technical initiatives such as Windows  migration, IP telephony and wireless design to name a few examples. The methodology begins with examining company business requirements. It is absolutely essential that you understand the company business model, business drivers and how they are growing from a business perspective. That will build the foundation for a design proposal that serves the business, technical and operational requirements of the company.

STEP 1: Business Requirements

Any design project starts with an understanding of what the company does and what they need to accomplish from a business perspective. This begins with an understanding of their business model, which really describes how their company works from an operational and business perspective to generate revenues and reduce costs. Many vendors today have conducted their own return on investment (ROI) studies for new implementations such as Unified Communications and Telephony. It is an effective sales tool that illustrates the cost benefits compared with investment over a specified period of time.

This is a list of some typical business drivers:

 • Reduce Operating Costs
 • Generate Revenue
 • Client Satisfaction
 • Employee Productivity

This is a list of some typical project business requirements:

 • Budget Constraints
 • Office Consolidations
 • Company Mergers and Acquisitions
 • Business Partner Connectivity
 • Telecommuter Remote Access  
 • Implement New Offices and Employees
 • New Data Center Applications
 • Reduce Network Outage Costs
 • Cost Effective Network Management
 • Vendor Contracts

STEP 2: Design Requirements

Now that you understand the basic business requirements of the company, you can determine the standard and specific design requirements. The design requirements process is focused on defining requirements from a technical perspective. Those requirements along with the business requirements will build the framework that is used to define infrastructure, security and management. Design requirements are defined as standard and miscellaneous. The standard design requirements are generic and represent those considered with many design projects. Miscellaneous requirements are those that aren’t defined with any of the standard requirements.

Standard Design Requirements

 • Performance
    
 • Availability

 • Scalability

 • Standards Compatibility

 • Rapid Deployment

STEP 3: Network Assessment

A network assessment is conducted after we have finished the business and design requirements of the company. A network assessment provides a quick snapshot of the current network with an examination of the infrastructure, performance, availability, management and security. That information is utilized for making effective strategy recommendations and design proposals to the client concerning specific information systems modifications. The network assessment model has 3 sequential activities, which are assessment, analysis and recommendations. The current network is examined using five primary surveys: infrastructure, performance, availability, management and security. When the surveys are completed, the information collected is then reviewed for trends, problems and issues that are negatively affecting the network.

STEP 4: Infrastructure Selection

After doing an network assessment we are ready to start selecting specific infrastructure components for the network design. This phase starts building the infrastructure with a specific sequence that promotes effective equipment selection and design. It is important that you consider business requirements, design requirements and the network assessment when building your infrastructure.

The following numbered list describes the specific infrastructure components and their particular sequence.

 1. Enterprise WAN Topology
 2. Campus Topology
 3. Traffic Model
 4. Equipment Selection
 5. Circuits
 6. Routing Protocol Design
 7. Addressing
 8. Naming Conventions
 9. IOS Services
10. Domain Name Services
11. DHCP Services

STEP 5: Security Strategy

We must now define a security strategy for securing the infrastructure. The need for enterprise network security shouldn’t be ignored with the proliferation of the Internet. Companies are continuing to leverage the public infrastructure for connecting national and international offices, business partners and new company acquisitions. The security requirements and network assessment recommendations should drive the selection of security equipment, protocols and processes. It identifies what assets must be protected, what users are allowed access and how those assets will be secured.

STEP 6: Network Management Strategy
 
This section will define a network management strategy for managing all equipment defined from infrastructure and security. It is necessary to define how the equipment is going to be monitored and determine if the current management strategy is adequate or if new applications, equipment, protocols and processes must be identified. Management components are then integrated with infrastructure and security to finish building the proposed design. These primary elements comprise any well-defined management strategy and should be considered when developing your strategy. 

 • 7 Management Groups
 • SNMP Applications
 • Monitored Devices and Events

STEP 7: Proof of Concept  

All infrastructure, security and management components must now be tested with a proof of concept plan. It is important to test the current design, configuration and IOS versions in a non-production environment or on the production network with limited disruption. Implementation of newer network modules at a router, for instance, could require that you change the current IOS version that is implemented. Making those changes could affect WAN or campus modules already installed at production routers. That is the real value of doing a proof of concept and certifying that the new equipment and IOS versions integrate with each device as well as the network. The following list describes the advantages of doing a proof of concept with your network design.  The proof of concept test results should be examined and used to modify current infrastructure, security and management specifications before generating a design proposal. The proof of concept model suggested here involves prototype design, equipment provisioning, defining tests, building equipment scripts and examining test results.  

 1. Prototype Design

 2. Provision Equipment

 3. Define Tests

 4. Build Equipment Scripts

 5. Review Test Results

STEP 8: Design Proposal/Review 

With the proof of concept finished, you are now ready to build a design proposal for the design review meeting. Your intended audience could be the Director, CIO, CTO, Senior Network Engineer, Consultant or anyone that is approving a budget for the project. It is important to present your ideas with clarity and professionalism. If a presentation is required, power point slides work well and could be used to support concepts from the design proposal document. The focus is on what comprises a standard design proposal and the sequence for presenting that information.

The working design proposal is presented to the client after addressing any concerns from proof of concept assurance testing. The design review is an opportunity for you to present your design proposal to the client and discuss any issues. It is an opportunity for the client to identify concerns they have and for the design engineer to clarify issues. The focus is to agree on any modifications, if required, and make changes to the infrastructure, security and management before implementation starts. Business and design requirements can change from when the project started which sometimes will necessitate changes to infrastructure, security and management specifications. Any changes should then go through proof of concept testing again before final changes to the design proposal.

STEP 9: Implementation

The final step will have us defining an implementation process for the specified design. This describes a suggested implementation methodology of the proposed design, which should have minimal disruption to the production network. As well it should be efficient and as cost effective as possible. As with previous methodologies there is a sequence that should be utilized as well.

Once the implementation is finished, there is monitoring of the network for any problems. Design and configuration modifications are then made to address any problems or concerns.

Shaun Hummel is author of Network Planning and Design Guide available at amazon.com and CiscoDesignBooks.com featuring Networking Books, eBooks, Certifications, Articles and Design Tools.

About the Author

Shaun Hummel, CCNP, is a Senior Network Engineer with 11 years experience in enterprise network planning, design, and implementation. He has worked for various private and public companies in Canada and the United States improving infrastructure, security, and management. He has written Network Planning and Design Guide, Cisco Wireless Network Design Guide and Network Assessment Guide. http://www.ciscodesignbooks.com

Building Small Office Network – Part1 – Network Design

Copco 2510-9963 Acadia Reusable To-Go Mug, 16-Ounce Capacity $5.69 Stop throwing away countless foam cups and help protect the environment with this insulated, re-usable travel coffee cup from Copco. This white cup features a brown, non-slip grip that resembles the sleeve on disposable cups. The lid quarter turns to seal and lock in place, which helps to prevent leaks. The entire cup is insulated, which makes it perfect for retaining either heated or cold beverag…

CDN Digital Programmable Probe Thermometer $23.62 Take the guesswork out of your cooking and baking and enjoy meals cooked to perfection. This digital thermometer has a temperature range from 32 to 482 degrees F, will display in both F and C, and includes easy-to-use programmable settings, a 24-hour count up and down timer, alarm and large display. Useful for Candy & Oil as well. It’s calibrated to the National Sanitation Foundation standards, th…

Crock-Pot SCVT650-PS 6-1/2-Quart Programmable Touch Screen Slow Cooker, Stainless Steel $79.99 6.5 Qt countdown touch screen e-lume slow cooker program cooking time automatically shifts to warm when cooking is done…

Boys of Fall $8.68 Studio: Sony Music Release Date: 08/23/2011…

Tom and Jerry – Spotlight Collection $10.76 Tom and Jerry, the animation franchise, lasted six decades and saw several geniuses of the form–Chuck Jones, Tex Avery, and Friz Freleng–have a hand in updating and refreshing the series in later years. But Tom and Jerry: The Spotlight Collection, Premiere Volume celebrates the original mastery of producer-directors William Hanna and Joseph Barbera, who took the familiar cat-chases-mouse concept…

The Social Network $5.24 All products are BRAND NEW and factory sealed. Fast shipping and 100% Satisfaction Guaranteed….

Star Wars: The Clone Wars – The Complete Season Three [Blu-ray] $28.98 The “Clone Wars” goes back to the original Star Wars film when Obi-Wan Kenobi tells Luke Skywalker that he was once a Jedi knight the same as your father and that they fought together in the Clone Wars. Since that moment fans have been obsessed with what the clone wars were. This new TV series takes place immediately after the events of Star Wars-Episode II: Attack of the Clones. The s…