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Capacity Planning for Enterprise Networks An Overview of Monitoring, Baselining, Traffic Analysis, and Performance Capacity Planning for Enterprise Networks An Overview of Monitoring, Baselining, Traffic Analysis, and Performance Optimization 1173_04 F 8_c 2 1

Jake Hartinger jharting@cisco. com 1173_04 F 8_c 2 2 Jake Hartinger [email protected] com 1173_04 F 8_c 2 2

Capacity Planning Outline • Introduction • Collection and Reporting of Capacity Information • WAN Capacity Planning Outline • Introduction • Collection and Reporting of Capacity Information • WAN Capacity Planning • LAN Capacity Planning • Upgrades and Service Level Agreements 1173_04 F 8_c 2 3

Increasing Importance of Capacity Planning • 85% of new application deployments fail to meet Increasing Importance of Capacity Planning • 85% of new application deployments fail to meet service level agreements • Increased network complexity • High-bandwidth multimedia applications and increased burstiness • Increased reliance on network services for business applications • Increased use of the network for non-business activities • More organizations upgrading existing networks and applications rather than building new networks 1173_04 F 8_c 2 4

Effective Capacity Management Gather Configuration and Traffic Information Implement Changes Performance Baselining Observe Statistics Effective Capacity Management Gather Configuration and Traffic Information Implement Changes Performance Baselining Observe Statistics Collect Capacity Data Analyze Traffic Solve Problems Plan Changes Evaluate What-If Analysis 1173_04 F 8_c 2 5

Resource Constraints or Bottlenecks • Network or end device CPU • Network or end Resource Constraints or Bottlenecks • Network or end device CPU • Network or end device I/O, forwarding rates and latency • Network or end device memory and buffering • Interface and pipe sizes • Speed and distance • Application characteristics 1173_04 F 8_c 2 6

Baseline Network Performance and Capacity • Interface utilization • Device CPU, memory, buffer, I/O Baseline Network Performance and Capacity • Interface utilization • Device CPU, memory, buffer, I/O utilization Gather Configuration and Traffic Information • Network overhead • Raw performance characteristics • Monthly or quarterly baseline report 1173_04 F 8_c 2 Implement Changes Performance Baselining Observe Statistics Collect Capacity Data Analyze Traffic Solve Problems Plan Changes Evaluate What-if Analysis 7

Baseline Application Performance and Capacity • Important for new or customer funded applications • Baseline Application Performance and Capacity • Important for new or customer funded applications • Determine application behavior and data flows • Rank mission critical applications • Compare against network capacity 1173_04 F 8_c 2 Gather Configuration and Traffic Information Implement Changes Performance Baselining Observe Statistics Collect Capacity Data Analyze Traffic Solve Problems Plan Changes Evaluate What-If Analysis 8

What-if Scenarios • Simulation applications • Lab application modeling Protocol Analyzer, WAN emulator, packet What-if Scenarios • Simulation applications • Lab application modeling Protocol Analyzer, WAN emulator, packet generator, NETSYS performance analyzer • Lab network modeling Gather Configuration and Traffic Information Implement Changes Performance Baselining Observe Statistics Collect Capacity Data Analyze Traffic Solve Problems Plan Changes Evaluate What-If Analysis NETSYS performance analyzer, lab network modeling 1173_04 F 8_c 2 9

Collecting and Reporting Capacity Information • Development of information collection plan Gather Configuration and Collecting and Reporting Capacity Information • Development of information collection plan Gather Configuration and Traffic Information • Tools for collecting capacity information • Defining capacity areas • Reporting and interpreting results 1173_04 F 8_c 2 Implement Changes Performance Baselining Observe Statistics Collect Capacity Data Analyze Traffic Solve Problems Plan Changes Evaluate What-If Analysis 10

Information to Collect • Link utilization • ATM parameters • CPU, process CPU • Information to Collect • Link utilization • ATM parameters • CPU, process CPU • Frame Relay DE, FECN, BECN, traffic-shaping parameters • Device throughput • Memory • Log file messages • Performance (ping response time) • Queue drops 1173_04 F 8_c 2 • Net. Flow and IP accounting • Application characteristics 11

Defining Capacity Areas • Useful for modeling, design strategies, capacity reporting, setting thresholds, and Defining Capacity Areas • Useful for modeling, design strategies, capacity reporting, setting thresholds, and service-level agreements • Examples of capacity areas LAN, core, distribution, and user WAN, critical WAN, and individual WAN link Access, ISDN, or dial • Network “class of service” • Application “class of service” 1173_04 F 8_c 2 12

Network “Class of Service” • Device thresholds exceeded by capacity area • Pipe size Network “Class of Service” • Device thresholds exceeded by capacity area • Pipe size thresholds exceeded by capacity area • Network availability metrics by capacity area • Threshold analysis Why was threshold exceeded? • Trends and SLA agreements • Recommendations and network changes 1173_04 F 8_c 2 13

Application “Class of Service” • Application model, “what-if” scenario • Application performance thresholds exceeded Application “Class of Service” • Application model, “what-if” scenario • Application performance thresholds exceeded by capacity area • Application threshold analysis Why was threshold exceeded? • Trends and SLA agreements • Recommendations and network changes 1173_04 F 8_c 2 14

Capacity Plan Strategy • • • 1173_04 F 8_c 2 Information to collect Application Capacity Plan Strategy • • • 1173_04 F 8_c 2 Information to collect Application and platform Archival period, (database capacity) Collection intervals Reporting mechanisms Monthly or quarterly capacity report Upgrade criteria Budget Resource or outsource? 15

Tools for Capacity Planning • NETSYS connectivity baseliner and solver • NETSYS performance baseliner Tools for Capacity Planning • NETSYS connectivity baseliner and solver • NETSYS performance baseliner and solver • Switch. Probe® products • Traffic. Director™ • Flow. Collector and Flow. Analyzer 1173_04 F 8_c 2 16

NETSYS Connectivity Baseliner and Solver • Test end-to-end reachability • Validate access list • NETSYS Connectivity Baseliner and Solver • Test end-to-end reachability • Validate access list • Determine routing loops • Evaluate routing protocol migration • Analyze and troubleshoot connectivity configuration • Conduct what-if analysis of changes and failure 1173_04 F 8_c 2 17

NETSYS Performance Baseliner and Solver • Analyze interaction between application traffic and network configuration NETSYS Performance Baseliner and Solver • Analyze interaction between application traffic and network configuration • Integrated data acquisition and analysis • Determine resource efficiency and end-toend performance analysis • Conduct what-if analysis of optimization changes • Add on to connectivity tools 1173_04 F 8_c 2 18

NETSYS Advisor • Automatic data collection • Maintains regularly updated status of network configurations, NETSYS Advisor • Automatic data collection • Maintains regularly updated status of network configurations, traffic and performance data, and observed routing tables • Automatic reporting, Web based • Gives operations staff and managers greater control of router configurations and end-toend network performance • Automatic diagnosis • Solve difficult routing problems • HTML/Java interface • Any user, any place, any time • Add on to connectivity tools 1173_04 F 8_c 2 19

Cisco Switch. Probe™ Products • Family of standalone enhanced RMON probes to monitor Fast Cisco Switch. Probe™ Products • Family of standalone enhanced RMON probes to monitor Fast Ethernet, FDDI, Token Ring, and Ethernet • Connect to critical interswitch and server links and to Port Analyzer, (SPAN), ports to provide full visibility of a switched internetwork 1173_04 F 8_c 2 20

Traffic. Director™ • Graphical user interface (GUI) based RMON console manager • Provides extensive Traffic. Director™ • Graphical user interface (GUI) based RMON console manager • Provides extensive graphing, alarm, logging, and reporting capabilities 1173_04 F 8_c 2 21

Flow Analysis • Flow. Collector Collect and manage network flows • Flow. Analyzer Display, Flow Analysis • Flow. Collector Collect and manage network flows • Flow. Analyzer Display, monitor, and analyze network flows • Requires Cisco IOS™ 11. 2 flow switching 1173_04 F 8_c 2 22

Reporting and Interpreting Results • Interpreting SNMP utilization levels • Understanding vendor thresholds • Reporting and Interpreting Results • Interpreting SNMP utilization levels • Understanding vendor thresholds • Setting exception levels 1173_04 F 8_c 2 23

Peak and Average Utilization Issues • Solution to narrow (Threshold) collection interval Capacity • Peak and Average Utilization Issues • Solution to narrow (Threshold) collection interval Capacity • Low collection interval = Parameter high overhead • Recommend >=5 minutes • Peak values not quite what they seem • Close to threshold indicates likely exceed condition 1173_04 F 8_c 2 Green Bar Represents SNMP Value Returned Time in Collection Intervals 24

Overhead Utilization • All non-user traffic SNMP Level 3 routing updates CDP Level 2 Overhead Utilization • All non-user traffic SNMP Level 3 routing updates CDP Level 2 signalling Other broadcast/multicast • Lowest level of traffic seen on link • Often 10% of link capacity or 20% of CPU • Important to understand measure in baselining 1173_04 F 8_c 2 25

Understanding Vendor Thresholds • Often less than media speed for one or more interfaces Understanding Vendor Thresholds • Often less than media speed for one or more interfaces in network device May be CPU, bus, I/O, memory, buffer, or interface limitations • Work with vendor to understand limitations, threshold behavior, and tuning capabilities • Use vendor thresholds to reset overall threshold levels for capacity reporting 1173_04 F 8_c 2 26

WAN Capacity Planning • Network and application capacity issues • Building manageable WAN solutions WAN Capacity Planning • Network and application capacity issues • Building manageable WAN solutions Gather Configuration and Traffic Information • WAN optimization • Device and bandwidth thresholds • Developing manager and user acceptance, service level agreement, and upgrade plan 1173_04 F 8_c 2 Implement Changes Performance Baselining Observe Statistics Collect Capacity Data Analyze Traffic Solve Problems Plan Changes Evaluate What-If Analysis 27

Network and Application Capacity Issues • Determining application and network bandwidth requirements • Application Network and Application Capacity Issues • Determining application and network bandwidth requirements • Application packet size affect on performance • Application data flows affect on performance • Batch requirements • Burst requirements • Latency issues • Speed and bandwidth 1173_04 F 8_c 2 • Network congestion behavior • Variable performance tolerance • Application prioritization • Affect of broadcast or multicast in NBMA environment • Behavior of UDP vs. TCP applications 28

Speed and Bandwidth • Ping from San Francisco to New York = 100 ms Speed and Bandwidth • Ping from San Francisco to New York = 100 ms • Ping from San Francisco to Los Angeles = 45 ms T-1 San Francisco • Ping from San Francisco to Los Angeles with frame congestion = 100 ms 1173_04 F 8_c 2 New York Frame Relay Cloud 56 kbps/16 kb ps CIR Los Angeles 29

WAN Connectivity Options Leased Line 56 kbps and Above Optimizes Speed Minimizes Variable Performance WAN Connectivity Options Leased Line 56 kbps and Above Optimizes Speed Minimizes Variable Performance Easier Management Highest Cost 1173_04 F 8_c 2 Frame Relay 56 kbps to 768 kbps Variable Performance ATM T-1 and Above Bandwidth Flexibility Cell Overhead More Performance Management Cloud Redundancy Lowest Cost Highest Bandwidth/$ 30

Frame Relay Subscription Example Boston 256 Kbps Port Host New York 512 Kbps Port Frame Relay Subscription Example Boston 256 Kbps Port Host New York 512 Kbps Port New York to Boston PVC 128 Kbps CIR Boston to New York PVC 32 Kbps CIR Dallas 128 Kbps Port Atlanta 128 Kbps Port New York to Dallas 64 Kbps CIR Dallas to New York 32 Kbps CIR New York to Atlanta 96 Kbps CIR Atlanta to New York 32 Kbps CIR 1173_04 F 8_c 2 31

ATM Subscription Example PBX 13 1 3 2 1 Carrier Cloud UBR Virtual Path ATM Subscription Example PBX 13 1 3 2 1 Carrier Cloud UBR Virtual Path CBR Virtual Circuit UBR Virtual Circuit VBR-RT Virtual Circuit 1173_04 F 8_c 2 PBX 32

WAN Optimization • Queuing methodologies FIFO queuing, weighted-fair queuing, custom queuing, priority queuing, split-DLCI WAN Optimization • Queuing methodologies FIFO queuing, weighted-fair queuing, custom queuing, priority queuing, split-DLCI queuing • Traffic shaping Frame Relay traffic shaping, generic traffic shaping, ATM traffic shaping, IP precedence, RED, WRED, CAR • Compression • Link overhead 1173_04 F 8_c 2 33

Queuing’s Premise • Getting better service is a matter of managing congested queues • Queuing’s Premise • Getting better service is a matter of managing congested queues • Over-all latency and bandwidth are constant Make some traffic absorb latency, and therefore give up bandwidth Shield other traffic from latency, and therefore gain bandwidth 1173_04 F 8_c 2 34

Queuing Comparison • FIFO queuing Least resources, simple Unpredictable Qo. S • Weighted-fair queuing Queuing Comparison • FIFO queuing Least resources, simple Unpredictable Qo. S • Weighted-fair queuing Predictable performance May be “unfair”, more sorting • Priority queuing • Custom queuing Base queuing on fiscal input Unpredictable in class • Split DLCI priority Solves Frame Relay congestion problem Unpredictable within queue, traffic lockout Based on access-list class Unpredictable performance for queue congestion, can cause traffic lockout 1173_04 F 8_c 2 35

FIFO Queuing Affect on Performance Milliseconds File Transfer Application X Ping 3500 3000 2500 FIFO Queuing Affect on Performance Milliseconds File Transfer Application X Ping 3500 3000 2500 2000 1500 1000 500 0 0 1173_04 F 8_c 2 50 100 150 200 250 300 350 400 450 500 550 600 36

Weighted-Fair Queuing Affect on Performance Milliseconds 300 File Transfer Application X Ping 250 200 Weighted-Fair Queuing Affect on Performance Milliseconds 300 File Transfer Application X Ping 250 200 150 100 50 0 0 1173_04 F 8_c 2 50 100 150 200 250 300 350 400 450 500 550 600 37

Traffic Shaping • ATM traffic shaping • Traffic classes, CBR, VBR-RT, VBR, ABR • Traffic Shaping • ATM traffic shaping • Traffic classes, CBR, VBR-RT, VBR, ABR • Service variables: PCR, CDV, CLR, MCR • Leaky bucket—flow control algorithm whereby a “bucket” receives credits at a rate equal to a user’s traffic-shaping parameters, overtime credits used at average rate but allows for bursts 1173_04 F 8_c 2 38

Traffic Shaping • Frame Relay traffic shaping Specified by mean-rate (normally CIR), burst rate, Traffic Shaping • Frame Relay traffic shaping Specified by mean-rate (normally CIR), burst rate, (Bc), and excess burst, (Be) Used to prevent loss in Frame Relay cloud and FECN/BECN reaction to improve Frame Relay performance • Generic traffic shaping Specified by mean-rate, burst-size, and excess burst size Used by service providers to subrate traffic on interfaces < E 1 1173_04 F 8_c 2 39

Traffic Shaping • IP precedence Prioritization within queuing mechanism using 3 bit IP packet Traffic Shaping • IP precedence Prioritization within queuing mechanism using 3 bit IP packet precedence field • RED Congestion avoidance for TCP applications; WRED based on IP precedence 1173_04 F 8_c 2 40

Traffic Shaping • CAR Allows network administrator to classify traffic in order to rate Traffic Shaping • CAR Allows network administrator to classify traffic in order to rate limit it based on a token bucket scheme • RSVP Reservation protocol for multimedia applications to guarantee bandwidth Will help overcome jitter, delay, loss, insufficient bandwidth 1173_04 F 8_c 2 41

Compression and Link Overhead • Compression Hardware compression Cisco CSA External device Software compression Compression and Link Overhead • Compression Hardware compression Cisco CSA External device Software compression FRF. 9 Cisco Frame Relay Voice compression • Minimal link overhead • All non-user traffic SNMP Level 3 routing updates CDP Level 2 signalling Other broadcast/multicast 32/24/16 ADPCM 16/8 CELP 1173_04 F 8_c 2 42

WAN Service Level Agreements and Upgrades • Baseline performance • Document consistent level of WAN Service Level Agreements and Upgrades • Baseline performance • Document consistent level of performance by application Number of users, transactions, performance Access support • Create upgrade criteria based on upgrade plan New application requirements Increasing users Exception reporting 1173_04 F 8_c 2 43

LAN Capacity Planning • Application and network requirements • Building manageable LAN solutions Gather LAN Capacity Planning • Application and network requirements • Building manageable LAN solutions Gather Configuration and Traffic Information • LAN optimization • Device and bandwidth thresholds • Developing manager, user acceptance, (service-level agreement) and upgrade plan 1173_04 F 8_c 2 Implement Changes Performance Baselining Observe Statistics Collect Capacity Data Analyze Traffic Solve Problems Plan Changes Evaluate What-If Analysis 44

Application and Network Requirements • Multicast and broadcast • Voice and video • File Application and Network Requirements • Multicast and broadcast • Voice and video • File transfers and backups (server to server) • Centralized servers/ workgroup servers • Routed and routing protocols • General data flows and volumes • Availability/redundancy 1173_04 F 8_c 2 45

Hubs, Switches, and Routers • Hubs • Router 10 or 100 Ethernet Any interface Hubs, Switches, and Routers • Hubs • Router 10 or 100 Ethernet Any interface 100 FDDI Inexpensive Complete and flexible level II, III filters No level II or III filter Rich features sets • Switches 10 or 100 Ethernet Expensive Forwarding rates lower than switches ATM Inexpensive No multicast/ broadcast filter High-forwarding rates 1173_04 F 8_c 2 46

LAN Solutions: Station Layer • Switched vs. non-switched Fast-Ethernet Hub • Collision domain for LAN Solutions: Station Layer • Switched vs. non-switched Fast-Ethernet Hub • Collision domain for Ethernet • Station bandwidth switched vs. non-switched FDDI/CDDI Hub • Broadcast effect on overall bandwidth and system CPU, “background radiation” Workgroup Switch • Station bandwidth requirements Workgroup Switch • FDDI, FE, Token Ring, ATM Workgroup Hub • Expectation for Multicast 1173_04 F 8_c 2 47

LAN Solutions: Distribution Layer • Protocols and broadcasts, IPX®, Apple. Talk, Net. BIOS • LAN Solutions: Distribution Layer • Protocols and broadcasts, IPX®, Apple. Talk, Net. BIOS • VLANs, RSM, and ISL • Uplink congestion point to backbone • Distribution layer servers • Load sharing, redundancy, (HSRP) 1173_04 F 8_c 2 48

LAN Solutions: Backbone Layer • Protocols and level III capacity issues • Level III LAN Solutions: Backbone Layer • Protocols and level III capacity issues • Level III switching performance • Bandwidth requirements • Hierarchy for capacity • Backbone layer servers • ATM backbones NBMA issues, VC issues • Load sharing, redundancy 1173_04 F 8_c 2 49

LAN Optimization • Bandwidth bottlenecks • Background radiation • Adding routing and switching • LAN Optimization • Bandwidth bottlenecks • Background radiation • Adding routing and switching • Multicast filtering, CGMP • Load sharing and redundancy • CPU and switching paths • Queues and buffers • Routing convergence 1173_04 F 8_c 2 50

LAN Service Level Agreements and Upgrades • Baseline network capacity • SLA based on LAN Service Level Agreements and Upgrades • Baseline network capacity • SLA based on availability/ performance model • Create upgrade criteria based on upgrade plan Multicast or other application requirement Increasing Enterprise, building/user model Exception reporting 1173_04 F 8_c 2 51

Upgrades and Service Level Agreements • Document expected performance/capacity improvement • Confirm expectations after Upgrades and Service Level Agreements • Document expected performance/capacity improvement • Confirm expectations after upgrade • Create new baseline measurements • Create new exception reporting measurements • Update service-level agreements 1173_04 F 8_c 2 52

Service Level Agreement • Network service level agreement Ping response and response time, capacity Service Level Agreement • Network service level agreement Ping response and response time, capacity Availability expectation by location or group Performance expectation by location or group Rules for non-conformance • Application service level agreement Application response time, (application call or ping) Network availability for application Performance for application Rules for non-conformance • Referenced document and available metrics 1173_04 F 8_c 2 53

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