DESIGNING CISCO NETWORKS
CHAPTER 1 DESIGN GOALS CHAPTER 2 ASSESSING THE EXISTING NETWORK AND IDENTIFYING CUSTOMER OBJECTIVES CHAPTER 3 APPLICATION CONSIDERATIONS CHAPTER 4 NETWORK TOPOLOGIES AND LAN DESIGN CHAPTER 5 WAN DESIGN CHAPTER 6 DESIGNING FOR SPECIFIC PROTOCOLS CHAPTER 7 THE DESIGN DOCUMENT AND CISCO NETWORK MANAGEMENT APPLICATIONS CHAPTER 8 BUILDING A PROTOTYPE OR PILOT CHAPTER 9 ADDITIONAL CASE STUDIES CONTENTS DESIGN GOALS TO GET YOU STARTED IN YOUR PREPARATION FOR THE CCDA EXAM, THIS CHAPTER CONTAINS A FRAMEWORK FOR GATHERING CUSTOMER OBJECTIVES WHEN DESIGNING A NETWORK THIS CHAPTER ALSO COVERS THE STEPS OF NETWORK DESIGN AND CONTAINS AN OVERVIEW OF ALL THE MAJOR TOPICS OF NETWORK DESIGN THE CHAPTERS THAT FOLLOW WILL COVER IN MORE DETAIL EACH OF THE TOPICS OVERVIEWED IN THIS CHAPTER “DO I KNOW THIS ALREADY?” QUIZ THE QUESTIONS IN THE FOLLOWING QUIZ ARE DESIGNED TO HELP YOU GAUGE HOW WELL YOU KNOW THE MATERIAL COVERED IN THIS CHAPTER COMPARE YOUR ANSWERS WITH THOSE FOUND IN APPENDIX A, “ANSWERS TO QUIZ QUESTIONS ” IF YOU ANSWERED MOST OR ALL OF THE QUESTIONS THOROUGHLY AND CORRECTLY, YOU MIGHT WANT TO SKIM THE CHAPTER AND PROCEED TO THE “Q&A” SECTION AT THE END OF THE CHAPTER IF YOU ?ND THAT YOU NEED TO REVIEW ONLY CERTAIN SUBJECT MATTER, SEARCH THE CHAPTER FOR THOSE SECTIONS THAT COVER THE OBJECTIVES YOU NEED TO REVIEW, AND THEN TEST YOURSELF BOTH WITH THESE QUESTIONS AND WITH THE “Q&A” QUESTIONS IF YOU ?ND THE FOLLOWING QUESTIONS TOO DIF?CULT, READ THE CHAPTER CAREFULLY UNTIL YOU FEEL THAT YOU CAN EASILY ANSWERS THESE AND THE “Q&A” QUESTIONS 1 WHAT TYPES OF QUESTIONS WOULD YOU ASK TO DETERMINE A CLIENT’S APPLICATION REQUIREMENTS? ___________________________________________________________________ ___________________________________________________________________ ___________________________________________________________________ 2 WHAT ARE SAMPLES OF BUSINESS CONSTRAINTS ON DESIGN? ___________________________________________________________________ ___________________________________________________________________ ___________________________________________________________________ 3 WHAT IS THE ?RST STEP IN NETWORK DESIGN? __________________________________________________________________ __________________________________________________________________ __________________________________________________________________ 4 IN THE FRAMEWORK OF SMALL TO MEDIUM-SIZED NETWORK DESIGN, WHAT SHOULD BE DONE IF THERE ARE PROTOCOL-RELATED PROBLEMS ON THE NETWORK? __________________________________________________________________ __________________________________________________________________ __________________________________________________________________ 5 WHAT INFORMATION IS GATHERED IN THE LOGICAL ASSESSMENT OF THE EXISTING NETWORK? __________________________________________________________________ __________________________________________________________________ __________________________________________________________________ 6 WHAT ARE THE THREE LAYERS OF HIERARCHICAL NETWORK DESIGN? __________________________________________________________________ __________________________________________________________________ __________________________________________________________________ 7 IF THERE ARE PROBLEMS INVOLVING MEDIA CONTENTION ON NETWORKS USING REPEATERS, WHAT SHOULD BE DONE TO RESOLVE IT? __________________________________________________________________ __________________________________________________________________ __________________________________________________________________ 8 WHAT ARE THE ?VE AREAS OF NETWORK MANAGEMENT? __________________________________________________________________ __________________________________________________________________ __________________________________________________________________ 9 IF YOU CUSTOMER HAS A SMALL NETWORK, WHAT TYPE OF DEMONSTRATION SHOULD BE USED? __________________________________________________________________ __________________________________________________________________ __________________________________________________________________ DESIGNING CISCO NETWORKS 10 IF HIGHER BANDWIDTH IS REQUIRED ON THE NETWORK, WHAT TECHNOLOGIES ARE SUGGESTED FOR SMALL TO MEDIUM-SIZED NETWORKS? ___________________________________________________________________ ___________________________________________________________________ ___________________________________________________________________ YOU CAN ?ND THE ANSWERS TO THESE QUESTIONS IN APPENDIX A, “ANSWERS TO QUIZ QUESTIONS ” DESIGNING CISCO NETWORKS FOUNDATION TOPICS CUSTOMER OBJECTIVES THE FOLLOWING CCDA OBJECTIVES ARE COVERED IN THIS SECTION: A CCDA SHOULD DESIGN NETWORKS BASED ON THE CUSTOMER’S OBJECTIVES IN OTHER WORDS, YOU WILL NEED TO ?ND OUT WHAT THE CUSTOMER WANTS TO SOLVE YOU THEN MUST CREATE A DESIGN THAT SOLVES THE NETWORKING PROBLEM OR ISSUE THE CUSTOMER IS HAVING THE ?RST STEP IN NETWORK DESIGN IS TO OBTAIN THE CUSTOMER’S REQUIREMENTS TO OBTAIN A COMPLETE PICTURE OF THE CUSTOMER’S OBJECTIVES, THE ENGINEER NEEDS TO DOCUMENT THE CLIENT’S BUSINESS REQUIREMENTS, TECHNICAL REQUIREMENTS, AND ANY BUSINESS AND POLITICAL CONSTRAINTS BUSINESS REQUIREMENTS OF THE CUSTOMER FOR THIS ASPECT OF DETERMINING THE CUSTOMER’S OBJECTIVES, THINK ABOUT THE PURPOSE OF THE PROJECT PROJECT HOW THE BUSINESS WILL IMPROVE FIND OUT IF THE NETWORK IS AFFECTING THE COMPANY’S CAPABILITY OR EFFECTIVENESS TO DEVELOP, PRODUCE, AND TRACK PRODUCTS FIND OUT IF ANY BUSINESS APPLICATIONS ARE BEING AFFECTED DETERMINE WHETHER THE COMPANY WILL BE AUDITED SCALABILITY IS A VERY IMPORTANT CONSIDERATION, AND IT IS WISE FOR THE NETWORK DESIGNER TO BUILD A NETWORK THAT CAN SCALE YOU SHOULD ?GURE OUT HOW MUCH THE COMPANY WILL GROW IN ONE YEAR OR IN ?VE YEARS TECHNICAL REQUIREMENTS OF THE CUSTOMER THINK ABOUT THE TYPE OF TECHNICAL PROBLEMS YOU ARE TRYING TO SOLVE CONSIDER THE NETWORK’S TOPOLOGY FOR EXAMPLE, IT MAY BE DIF?CULT TO INTRODUCE ETHERNET TO A CUSTOMER THAT RELIGIOUSLY USES TOKEN RING ALSO CONSIDER THE COMPANY’S USE OF MODERN TECHNOLOGIES FIND OUT WHETHER THE CLIENT IS WILLING TO EXPERIMENT WITH THE LATEST, BLEEDING-EDGE TECHNOLOGIES KEEP IN MIND SCALING ISSUES; DECIDE WHETHER SWITCHED ETHERNET WILL PROVIDE THE NECESSARY BANDWIDTH OR WHETHER FAST ETHERNET IS NECESSARY TO SCALE THE NETWORK DESIGN A NETWORK THAT MEETS A CUSTOMER’S REQUIREMENTS FOR PERFORMANCE, SECURITY, CAPACITY, AND SCALABILITY DOCUMENT THE CUSTOMER’S CURRENT APPLICATIONS, PROTOCOLS, TOPOLOGY, AND NUMBER OF USERS DOCUMENT THE CUSTOMER’S BUSINESS ISSUES THAT ARE RELEVANT TO A NETWORK DESIGN PROJECT DESIGNING CISCO NETWORKS TECHNICAL REQUIREMENTS CAN BE DIVIDED INTO THE FOLLOWING AREAS: PERFORMANCE REQUIREMENTS APPLICATIONS REQUIREMENTS NETWORK MANAGEMENT REQUIREMENTS SECURITY REQUIREMENTS PERFORMANCE REQUIREMENTS DETERMINE THE FOLLOWING PERFORMANCE REQUIREMENTS: IDENTIFY ANY ISSUES CONCERNING NETWORK LATENCY AND RESPONSE TIMES FIND OUT IF THERE IS HIGH UTILIZATION ON LAN SEGMENTS OR WAN LINKS DETERMINE HOW OFTEN THE WAN LINKS GO DOWN APPLICATION REQUIREMENTS CONSIDER EXISTING APPLICATION INTEGRATION THE NETWORK DESIGN WILL NEED TO SEAMLESSLY ACCOMMODATE THE EXISTING APPLICATIONS INVESTIGATE THE CURRENT APPLICATION ?OWS, AND INCORPORATE THOSE INTO THE NETWORK DESIGN DETERMINE THE FOLLOWING APPLICATION REQUIREMENTS: FIND OUT WHAT NEW APPLICATIONS HAVE BEEN INTRODUCED TO THE NETWORK DETERMINE THE NUMBER OF USERS USING THESE APPLICATIONS FIND OUT THE TRAF?C ?OW FOR THESE APPLICATIONS IDENTIFY WHAT NEW PROTOCOLS ARE BEING INTRODUCED TO THE NETWORK DETERMINE WHAT APPLICATIONS ARE USED DURING THE DAYTIME HOURS AND WHAT ARE USED DURING THE NIGHTTIME HOURS DETERMINE THE TIME OF DAY THAT REPRESENTS THE PEAK USAGE HOURS OF APPLICATIONS NETWORK MANAGEMENT REQUIREMENTS DETERMINE THE FOLLOWING NETWORK MANAGEMENT REQUIREMENTS: DETERMINE HOW THE NETWORK IS MANAGED DETERMINE WHETHER THERE IS A NETWORK MANAGEMENT STATION TO VIEW NETWORK PERFORMANCE AND FAULTS ASCERTAIN WHETHER THERE ARE ANY ACCOUNTING AND SECURITY MANAGEMENT REQUIREMENTS FIND OUT WHETHER THE STAFF IS TRAINING ON THE NETWORK MANAGEMENT APPLICATIONS FIND OUT WHETHER THERE IS A STATION FOR CON?GURATION MANAGEMENT