Chapter 1: Analyzing The Cisco Enterprise Campus Architecture

1. Chapter 1: Analyzing The Cisco Enterprise Campus Architecture CCNP SWITCH: Implementing IP Switching

2. Chapter 1 Objectives • Describe 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.

3. Introduction to Enterprise Campus Network Design

4. Enterprise Network • Core (Backbone) • Campus • Data Center • Branch • WAN • Internet Edge

5. Regulatory Standards (U.S.) • There may be several legal regulations that have an impact on a network’s design. • US regulations on networks include: • Health Insurance Portability and Accountability Act (HIPAA) • Sarbanes-Oxley Act • “Records to Be Preserved by Certain Exchange Members, Brokers and Dealers”: Securities and Exchange Commission (SEC) Rule 17a-4

6. Campus Designs • Modular - 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.

7. Multilayer Switches in Campus Networks • Hardware-based routing using Application-Specific Integrated Circuits (ASICs) • RIP, OSPF, and EIGRP are supported • Layer 3 switching speeds approximate that of Layer 2 switches • Layer 4 and Layer 7 switching supported on some switches • Future: Pure Layer 3 environment leveraging inexpensive L3 access layer switches

8. Cisco Switches • Catalyst 6500 Family – used in campus, data center, and core as well as WAN and branch • Up to 13 slots and 16 10-Gigabit Ethernet interfaces • Redundant power supplies, fans, and supervisor engines • Runs Cisco IOS • Catalyst 4500 Family – used in distribution layer and in collapsed core environments • Up to 10 slots and several 10-Gigabit Ethernet interfaces • Runs Cisco IOS • Catalyst 3560 and 3750 Families – used in fixed-port scenarios at the access and distribution layers • Nexus 2000, 5000, and 7000 Families – NX-OS based modular data center switches

9. Multilayer Switching Miscellany • ASIC-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.

10. Traffic Types • Network Management – BPDU, CDP, SNMP, RMON, SSH traffic (for example); low bandwidth • IP Telephony – Signaling traffic and encapsulated voice traffic; low bandwidth • IP Multicast – IP/TV and market data applications; intensive configuration requirements; very high bandwidth • Normal Data – File and print services, email, Internet browsing, database access, shared network applications; low to medium bandwidth • Scavenger 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

11. Client-Server Applications • Mail servers • File servers • Database servers • Access to applications is fast, reliable, and secure

12. Client-Enterprise Edge Applications • Servers on the enterprise edge, exchanging data between an organization and its public servers • Examples: external mail servers, e-commerce servers, and public web servers • Security and high availability are paramount

13. 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.

14. Borderless Networks • Enterprise 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 software • Unifying computation, storage, and network • Policy throughout the unified system • Provides a platform for business innovation. • Serves as the foundation for rich-media communications.

15. Enterprise Campus Design

16. Building Access, Building Distribution, and Building Core Layers • Building 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.

17. Core Layer • Aggregates distribution layer switches. • Implements scalable protocols and technologies and load balancing. • High-speed layer 3 switching using 10-Gigabit Ethernet. • Uses redundant L3 links.

18. Distribution Layer • High availability, fast path recovery, load balancing, QoS, and security • Route summarization and packet manipulation • Redistribution point between routing domains • Packet filtering and policy routing to implement policy-based connectivity • Terminate VLANs • First Hop Redundancy Protocol

19. Access Layer • High 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.

20. Small Campus Network • <200 end devices • Collapsed core • Catalyst 3560 and 2960G switches for access layer • Cisco 1900 and 2900 routers to interconnect branch/WAN

21. Medium Campus Network • 200-1000 end devices • Redundant multilayer switches at distribution layer • Catalyst 4500 or 6500 switches

22. Large Campus Network • >2000 end users • Stricter adherence to core, distribution, access delineation • Catalyst 6500 switches in core and distribution layers • Nexus 7000 switches in data centers • Division of labor amongst network engineers

23. Data Center Infrastructure • Core layer – high-speed packet switching backplane • Aggregation layer – service module integration, default gateway redundancy, security, load balancing, content switching, firewall, SSL offload, intrusion detection, network analysis • Access layer – connects servers to network

24. PPDIOO Lifecycle Approach to Network Design and Implementation

25. PPDIOO Phases • Prepare – 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.

26. Lifecycle Approach • Lowering 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

27. Lifecycle Approach (1) • Benefits: • Lowering the total cost of network ownership • Increasing network availability • Improving business agility • Speeding access to applications and services • Lower 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 tools

28. Lifecycle Approach (2) • Improve high availability: • Assessing the network’s 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 alerts • Gain 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 demonstrating • that the network is functioning as specified • Expertly installing, configuring, and integrating system components • Continually enhancing performance • Accelerate 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

29. Planning a Network Implementation • Implementation Components: • Description of the step • Reference to design documents • Detailed implementation guidelines • Detailed roll-back guidelines in case of failure • Estimated time needed for implementation • Summary Implementation Plan – overview of implementation plan • Detailed 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

30. Chapter 1 Summary • Evolutionary 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.

31. Chapter 1 Labs • Lab 1-1Clearing a Switch • Lab 1-2Clearing a Switch Connected to a Larger Network

32. Resources • www.cisco.com/en/US/products