SWITCH Ch 1

Chapter 1: Analyzing The Cisco Enterprise Campus ArchitectureCCNP SWITCH: Implementing IP Switching 2007 2010, Cisco Systems, Inc. All rights reserved.Cisco PublicCourse v6 Chapter ##Chapter ## 2007 2010, Cisco Systems, Inc. All rights reserved.Cisco Public1Cisco Networking Academy ProgramCCNP SWITCH: Implementing IP SwitchingChapter 1: Analyzing The Cisco Enterprise Campus Architecture

2006, Cisco Systems, Inc. All rights reserved.Chapter 1 ObjectivesDescribe common campus design options and how design choices affect implementation and support of a campus LAN.Describe the access, distribution, and core layers.Describe small, medium, and large campus network designs.Describe the prepare, plan, design, implement, operate, optimize (PPDIOO) methodology.Describe the network lifecycle approach to campus design.Chapter ## 2007 2010, Cisco Systems, Inc. All rights reserved.Cisco Public2Chapter 1 Objectives 2006, Cisco Systems, Inc. All rights reserved.

Introduction to Enterprise Campus Network DesignChapter ## 2007 2010, Cisco Systems, Inc. All rights reserved.Cisco Public3 2006, Cisco Systems, Inc. All rights reserved.Enterprise NetworkCore (Backbone)CampusData CenterBranchWANInternet Edge

Chapter ## 2007 2010, Cisco Systems, Inc. All rights reserved.Cisco PublicThe core interconnects the campus access, the data center, and WAN portions of the network.The campus is the portion of the computing infrastructure that provides access to network communication services and resources to end users and devices spread over a single geographic location. The data center is a facility used to house computing systems and associated components.The branch/WAN portion of the enterprise network contains the routers, switches, and so on to interconnect a main office to branch offices or other main officesInternet Edge is the portion of the enterprise network that encompasses the routers, switches, firewalls, and network devices that interconnect the enterprise network to the Internet. The Internet Edge includes technology necessary to connect telecommuters from the Internet to services in the enterprise.4 2006, Cisco Systems, Inc. All rights reserved.Regulatory Standards (U.S.)There may be several legal regulations that have an impact on a networks design.US regulations on networks include:Health Insurance Portability and Accountability Act (HIPAA)Sarbanes-Oxley ActRecords to Be Preserved by Certain Exchange Members, Brokers and Dealers: Securities and Exchange Commission (SEC) Rule 17a-4

Chapter ## 2007 2010, Cisco Systems, Inc. All rights reserved.Cisco Public5HIPAA ensures that an integrated security infrastructure keeps medical information safe: www.hipaa.com.Sarbanes-Oxley Act specifies legal standards for maintaining the integrity of financial data, and requires public companies to have multiple redundant data centers with synchronous, real-time copies of financial data: www.sarbanes-oxley.com.SEC primary rule 17a-4 allows broker-dealers to store records electronically, including electronic communications and messaging such as email and instant messages: www.sec.gov.

2006, Cisco Systems, Inc. All rights reserved.Campus DesignsModular - easily supports growth and change. Scaling the network is eased by adding new modules in lieu of complete redesigns. Resilient - proper high-availability (HA) characteristics result in near-100% uptime. Flexible - change in business is a guarantee for any enterprise. These changes drive campus network requirements to adapt quickly.Chapter ## 2007 2010, Cisco Systems, Inc. All rights reserved.Cisco Public6 2006, Cisco Systems, Inc. All rights reserved.Multilayer Switches in Campus NetworksHardware-based routing using Application-Specific Integrated Circuits (ASICs)RIP, OSPF, and EIGRP are supportedLayer 3 switching speeds approximate that of Layer 2 switchesLayer 4 and Layer 7 switching supported on some switchesFuture: Pure Layer 3 environment leveraging inexpensive L3 access layer switches

Chapter ## 2007 2010, Cisco Systems, Inc. All rights reserved.Cisco PublicLayer 4 switching enables load balancing based on Layer 4 port numberLayer 7 switching uses Network-Based Application Recognition (NBAR) to permit or deny traffic based on data passed by an application7 2006, Cisco Systems, Inc. All rights reserved.Cisco SwitchesCatalyst 6500 Family used in campus, data center, and core as well as WAN and branchUp to 13 slots and 16 10-Gigabit Ethernet interfacesRedundant power supplies, fans, and supervisor enginesRuns Cisco IOSCatalyst 4500 Family used in distribution layer and in collapsed core environmentsUp to 10 slots and several 10-Gigabit Ethernet interfacesRuns Cisco IOSCatalyst 3560 and 3750 Families used in fixed-port scenarios at the access and distribution layersNexus 2000, 5000, and 7000 Families NX-OS based modular data center switchesChapter ## 2007 2010, Cisco Systems, Inc. All rights reserved.Cisco Public86500Scalable modular switch up to 13 slots Supports up to 16 10-Gigabit Ethernet interfaces per slot in an over-subscription model Up to 80 Gbps of bandwidth per slot in current generation hardware Supports Cisco IOS with a plethora of Layer 2 and Layer 3 switching features Optionally supports up to Layer 7 features with specialized modules Integrated redundant and high-available power supplies, fans, and supervisor engineers Supports Layer 3 Non-Stop Forwarding (NSF) whereby routing peers are maintained during a supervisor switchover. Backward capability and investment protection have lead to a long life cycle4500Scalable module switch with up to 10 slots Supports multiple 10 Gigabit Ethernet interfaces per slot Supports Cisco IOS Supports both Layer 2 switching and Layer 3 switching Optionally supports integrated redundant and high-available power supplies and supervisor engines 4948G, 3750, and 3560Available in a variety of fixed port configurations with up to 48 1-Gbps access layer ports and 4 10-Gigabit Ethernet interfaces for uplinks to distribution layer Supports Cisco IOS Supports both Layer 2 and Layer 3 switching Not architected with redundant hardware 2000Available in a variety of fixed port configurations with up to 48 1-Gbps access layer ports and multiple 10-Gigabit Ethernet uplinks Supports Cisco IOS Supports only Layer 2 switching Not architected with redundant hardware Nexus 7000 Modular switch with up to 18 slots Supports up to 230 Gbps per slot Supports Nexus OS (NX-OS) 10-slot chassis is built on front-to-back airflow Supports redundant supervisor engines, fans, and power supplies Nexus 5000 and 2000Low-latency switches designed for deployment in the access layer of the data center. Nexus 5000 switches are designed for 10-Gigabit Ethernet applications and also support Fibre Channel over Ethernet (FCOE) 2006, Cisco Systems, Inc. All rights reserved.Multilayer Switching MiscellanyASIC-based (hardware) switching is supported even with QoS and ACLs, depending on the platform; 6500 switches support hardware-based switching with much larger ACLs than 3560 switches.ASICs on Catalyst switches work in tandem with ternary content addressable memory (TCAM) and packet-matching algorithms for high-speed switching.

Catalyst 6500 switches with a Supervisor Engine 720 and a Multilayer Switch Feature Card (MSFC3) must software-switch all packets requiring Network Address Translation.Unlike CPUs, ASICs scale in switching architectures. ASICs integrate onto individual line modules of Catalyst switches to hardware-switch packets in a distributed manner.Chapter ## 2007 2010, Cisco Systems, Inc. All rights reserved.Cisco PublicASICs do have memory limitations, depending on the platform.

9 2006, Cisco Systems, Inc. All rights reserved.Traffic TypesNetwork Management BPDU, CDP, SNMP, RMON, SSH traffic (for example); low bandwidthIP Telephony Signaling traffic and encapsulated voice traffic; low bandwidthIP Multicast IP/TV and market data applications; intensive configuration requirements; very high bandwidthNormal Data File and print services, email, Internet browsing, database access, shared network applications; low to medium bandwidthScavenger Class All traffic with protocols or patterns that exceed normal data flows; less than best-effort traffic, such as peer-to-peer traffic (instant messaging, file sharing, IP phone calls, video conferencing); medium to high bandwidth

Chapter ## 2007 2010, Cisco Systems, Inc. All rights reserved.Cisco Public10 2006, Cisco Systems, Inc. All rights reserved.Client-Server ApplicationsMail serversFile serversDatabase serversAccess to applications is fast, reliable, and secure

Chapter ## 2007 2010, Cisco Systems, Inc. All rights reserved.Cisco PublicNetwork bandwidth used to be costly, but today it is cost-effective compared to the application requirements. Switch delay is insignificant for most client/server applications with high-performance Layer 3 switches, locating the servers centrally rather than in the workgroup is technically feasible and reduces support costs. Low latency is extremely important to financial and market data applicationsNexus 7000 family switches are ideal for thisFor example, traders need access to trading applications anytime with good response times to be competitive with other traders.The ideal is to place servers in a common server farm in a data center.Use of server farms in data centers requires a network infrastructure that is highly resilient and redundant and that provides adequate throughput. Typically, high-end LAN switches with the fastest LAN technologies, such as 10 Gigabit Ethernet, are deployed. For Cisco switches, the current trend is to deploy Nexus switches while the campus deploys Catalyst switches. The use of the Catalyst switches in the campus and Nexus in the data center is a market transition from earlier models that used Catalyst switches throughout the enterprise.Nexus switches do not run the traditional Cisco IOS found on Cisco routers and switches. Instead they run Nexus OS (NX-OS) which was derived from the SAN-OS found on the Cisco MDS SAN platform.Nexus switches have a higher cost than Catalyst switches and do not support telephony, inline power, firewall, or load-balancing services. However, Nexus switches do support higher throughput, lower latency, high-availability, and high-density 10-Gigabit Ethernet suited for data center environments.

11 2006, Cisco Systems, Inc. All rights reserved.Client-Enterprise Edge ApplicationsServers on the enterprise edge, exchanging data between an organization and its public serversExamples: external mail servers, e-commerce servers, and public web serversSecurity and high availability are paramount

Chapter ## 2007 2010, Cisco Systems, Inc. All rights reserved.Cisco Public12 2006, Cisco Systems, Inc. All rights reserved.Service-Oriented Network Architecture (SONA)Application Layer business and collaboration applications; meet business requirements leveraging interactive services layer.Interactive Services Layer enable efficient allocation of resources to applications and business processes through the networked infrastructure.Networked Infrastructure Layer where all IT resources interconnect.

Chapter ## 2007 2010, Cisco Systems, Inc. All rights reserved.Cisco PublicSONA embeds application-level intelligence into the network infrastructure elements so that the network can recognize and better support applications and services.Benefits: Convergence, virtualization, intelligence, security, and integration in all areas of the network infrastructureCost savingsIncreased productivityFaster deployment of new services and applicationsEnhanced business processesSONA is strictly a model to guide network designs. When designing the campus portion of the enterprise network, you need to understand SONA only from a high level as most of the focus of the campus design is centered on features and functions of Cisco switching.

13 2006, Cisco Systems, Inc. All rights reserved.Borderless NetworksEnterprise architecture launched by Cisco in October 2009.Model enables businesses to transcend borders, access resources anywhere, embrace business productivity, and lower business and IT costs.Focuses more on growing enterprises into global companies.Technical architecture based on three principles:Decoupling hardware from softwareUnifying computation, storage, and networkPolicy throughout the unified systemProvides a platform for business innovation.Serves as the foundation for rich-media communications.Chapter ## 2007 2010, Cisco Systems, Inc. All rights reserved.Cisco Public14 2006, Cisco Systems, Inc. All rights reserved.

Enterprise Campus DesignChapter ## 2007 2010, Cisco Systems, Inc. All rights reserved.Cisco Public15 2006, Cisco Systems, Inc. All rights reserved.Building Access, Building Distribution, and Building Core LayersBuilding Core Layer: high-speed campus backbone designed to switch packets as fast as possible; provides high availability and adapts quickly to changes.Building Distribution Layer: aggregate wiring closets and use switches to segment workgroups and isolate network problems.Building Access Layer: grant user access to network devices.

Chapter ## 2007 2010, Cisco Systems, Inc. All rights reserved.Cisco Public16 2006, Cisco Systems, Inc. All rights reserved.Core LayerAggregates distribution layer switches.Implements scalable protocols and technologies and load balancing.High-speed layer 3 switching using 10-Gigabit Ethernet.Uses redundant L3 links.

Chapter ## 2007 2010, Cisco Systems, Inc. All rights reserved.Cisco PublicWithout a core layer, the distribution layer switches need to be fully meshed. This design is difficult to scale and increases the cabling requirements because each new building distribution switch needs full-mesh connectivity to all the distribution switches.As a recommended practice, deploy a dedicated campus core layer to connect three or more physical segments or four or more pairs of building distribution switches in a large campus. Core layer constituents and functions depend on the size and type of the network. Not all campus implementations require a campus core. Optionally, campus designs can combine the core and distribution layer functions at the distribution layer for a smaller topology.17 2006, Cisco Systems, Inc. All rights reserved.Distribution LayerHigh availability, fast path recovery, load balancing, QoS, and securityRoute summarization and packet manipulationRedistribution point between routing domainsPacket filtering and policy routing to implement policy-based connectivityTerminate VLANsFirst Hop Redundancy Protocol

Chapter ## 2007 2010, Cisco Systems, Inc. All rights reserved.Cisco Public18 2006, Cisco Systems, Inc. All rights reserved.Access LayerHigh availability supported by many hardware and software features, such as redundant power supplies and First Hop Redundancy Protocols (FHRP). Convergence provides inline Power over Ethernet (PoE) to support IP telephony and wireless access points.Security includes port security, DHCP snooping, Dynamic ARP inspection, IP source guard.

Chapter ## 2007 2010, Cisco Systems, Inc. All rights reserved.Cisco Public19 2006, Cisco Systems, Inc. All rights reserved.Small Campus Network2000 end usersStricter adherence to core, distribution, access delineationCatalyst 6500 switches in core and distribution layersNexus 7000 switches in data centersDivision of labor amongst network engineersChapter ## 2007 2010, Cisco Systems, Inc. All rights reserved.Cisco Public22 2006, Cisco Systems, Inc. All rights reserved.Data Center InfrastructureCore layer high-speed packet switching backplaneAggregation layer service module integration, default gateway redundancy, security, load balancing, content switching, firewall, SSL offload, intrusion detection, network analysisAccess layer connects servers to network

Chapter ## 2007 2010, Cisco Systems, Inc. All rights reserved.Cisco PublicData center design as part of the enterprise network is based on a layered approach to improve scalability, performance, flexibility, resiliency, and maintenance.Multitier HTTP-based applications supporting web, application, and database tiers of servers dominate the multitier data center model. The access layer network infrastructure can support both Layer 2 and Layer 3 topologies, and Layer 2 adjacency requirements fulfilling the various server broadcast domain or administrative requirements. Layer 2 in the access layer is more prevalent in the data center because some applications support low latency via Layer 2 domains. Most servers in the data center consist of single and dual attached one rack unit (RU) servers, blade servers with integrated switches, blade servers with pass-through cabling, clustered servers, and mainframes with a mix of oversubscription requirements.Multiple aggregation modules in the aggregation layer support connectivity scaling from the access layer. The aggregation layer supports integrated service modules providing services such as security, load balancing, content switching, firewall, SSL offload, intrusion detection, and network analysis. 23 2006, Cisco Systems, Inc. All rights reserved.

PPDIOO Lifecycle Approach to Network Design and ImplementationChapter ## 2007 2010, Cisco Systems, Inc. All rights reserved.Cisco Public24 2006, Cisco Systems, Inc. All rights reserved.PPDIOO PhasesPrepare establish organizational requirements.Plan identify initial network requirements.Design comprehensive, based on planning outcomes.Implement build network according to design.Operate maintain network health.Optimize proactive management of network.Chapter ## 2007 2010, Cisco Systems, Inc. All rights reserved.Cisco Public25Prepare: Involves establishing the organizational requirements, developing a network strategy, and proposing a high-level conceptual architecture identifying technologies that can best support the architecture. The prepare phase can establish a financial justification for network strategy by assessing the business case for the proposed architecture.Plan: Involves identifying initial network requirements based on goals, facilities, user needs, and so on. The plan phase involves characterizing sites and assessing any existing networks and performing a gap analysis to determine whether the existing system infrastructure, sites, and the operational environment can support the proposed system. A project plan is useful for helping manage the tasks, responsibilities, critical milestones, and resources required to implement changes to the network. The project plan should align with the scope, cost, and resource parameters established in the original business requirements.Design: The initial requirements that were derived in the planning phase drive the activities of the network design specialists. The network design specification is a comprehensive detailed design that meets current business and technical requirements, and incorporates specifications to support availability, reliability, security, scalability, and performance. The design specification is the basis for the implementation activities. Implement: The network is built or additional components are incorporated according to the design specifications, with the goal of integrating devices without disrupting the existing network or creating points of vulnerability. Operate: Operation is the final test of the appropriateness of the design. The operational phase involves maintaining network health through day-to-day operations, including maintaining high availability and reducing expenses. The fault detection, correction, and performance monitoring that occur in daily operations provide the initial data for the optimization phase. Optimize: Involves proactive management of the network. The goal of proactive management is to identify and resolve issues before they affect the organization. Reactive fault detection and correction (troubleshooting) is needed when proactive management cannot predict and mitigate failures. In the PPDIOO process, the optimization phase can prompt a network redesign if too many network problems and errors arise, if performance does not meet expectations, or if new applications are identified to support organizational and technical requirements. 2006, Cisco Systems, Inc. All rights reserved.Lifecycle ApproachLowering the total cost of network ownership Increasing network availability Improving business agility Speeding access to applications and services Identifying and validating technology requirements Planning for infrastructure changes and resource requirements

Developing a sound network design aligned with technical requirements and business goals Accelerating successful implementation Improving the efficiency of your network and of the staff supporting it Reducing operating expenses by improving the efficiency of operational processes and tools Chapter ## 2007 2010, Cisco Systems, Inc. All rights reserved.Cisco Public26 2006, Cisco Systems, Inc. All rights reserved.Lifecycle Approach (1)Benefits:Lowering the total cost of network ownershipIncreasing network availabilityImproving business agilitySpeeding access to applications and servicesLower costs:Identify and validate technology requirements Plan for infrastructure changes and resource requirements Develop a sound network design aligned with technical requirements and business goals Accelerate successful implementation Improve the efficiency of your network and of the staff supporting it Reduce operating expenses by improving the efficiency of operational processes and toolsChapter ## 2007 2010, Cisco Systems, Inc. All rights reserved.Cisco Public27 2006, Cisco Systems, Inc. All rights reserved.Lifecycle Approach (2)Improve high availability:Assessing the networks security state and its capability to support the proposed design Specifying the correct set of hardware and software releases, and keeping them operational and current Producing a sound operations design and validating network operations Staging and testing the proposed system before deployment Improving staff skills Proactively monitoring the system and assessing availability trends and alertsGain business agility:Establishing business requirements and technology strategies Readying sites to support the system that you want to implement Integrating technical requirements and business goals into a detailed design and demonstratingthat the network is functioning as specified Expertly installing, configuring, and integrating system components Continually enhancing performanceAccelerate access to network applications and services:Assessing and improving operational preparedness to support current and planned network technologies and services Improving service-delivery efficiency and effectiveness by increasing availability, resource capacity, and performance Improving the availability, reliability, and stability of the network and the applications running on it Managing and resolving problems affecting your system and keeping software applications current Chapter ## 2007 2010, Cisco Systems, Inc. All rights reserved.Cisco Public28 2006, Cisco Systems, Inc. All rights reserved.Planning a Network ImplementationImplementation Components:Description of the stepReference to design documentsDetailed implementation guidelinesDetailed roll-back guidelines in case of failureEstimated time needed for implementationSummary Implementation Plan overview of implementation planDetailed Implementation Plan describes exact steps necessary to complete the implementation phase, including steps to verify and check the work of the network engineers implementing the plan

Chapter ## 2007 2010, Cisco Systems, Inc. All rights reserved.Cisco PublicAlso, a rollback plan shall be identified for each step of the implementation phase in case its deployment fails or unforeseen problems arise.29 2006, Cisco Systems, Inc. All rights reserved.Chapter 1 SummaryEvolutionary changes are occurring within the campus network. Evolution requires careful planning and deployments based on hierarchical designs. As the network evolves, new capabilities are added, usually driven by application data flows. Implementing the increasingly complex set of business-driven capabilities and services in the campus architecture is challenging if done in a piecemeal fashion. Any successful architecture must be based on a foundation of solid design theory and principles. The adoption of an integrated approach based on solid systems design principles is a key to success.

Chapter ## 2007 2010, Cisco Systems, Inc. All rights reserved.Cisco Public30 2006, Cisco Systems, Inc. All rights reserved.Lab 1-1Clearing a Switch Lab 1-2Clearing a Switch Connected to a Larger Network Chapter 1 LabsChapter ## 2007 2010, Cisco Systems, Inc. All rights reserved.Cisco PublicResourceswww.cisco.com/en/US/products

Chapter ## 2007 2010, Cisco Systems, Inc. All rights reserved.Cisco Public32 2006, Cisco Systems, Inc. All rights reserved.

Chapter ## 2007 2010, Cisco Systems, Inc. All rights reserved.Cisco Public33 2006, Cisco Systems, Inc. All rights reserved.