---

Content Overview This module looks at the need for multilayer switches within Cisco’s overall network design. A review of Intelligent Information Networks (IIN) and Service-Oriented Network Architectures (SONA) sets the groundwork for the course. Additionally, a quick overview of the characteristics of Layer 2 and Layer 3 networks aids in identifying the reasons for using a multilayer switch. This module begins by discussing operational problems found in non-hierarchical networks at Layers 2 and 3 of the Open Systems Interconnection (OSI) model. The Enterprise Composite Network Model (ECNM) is then introduced, and the features and benefits of ECNM are explained. Issues that exist in traditionally designed networks can be resolved by applying this state-of-the-art design to their networks.

---

Content 1.1 Introducing Campus Networks 1.1.1 Intelligent Information Network and Service-Oriented Network Architecture Intelligent Information Network (IIN) encompasses these features :

• Integration of networked resources and information assets that have been largely unlinked: The current converged networks that integrate voice, video, and data require Information Technology (IT) departments to link the IT infrastructure more closely with the network.
• Intelligence across multiple products and infrastructure layers: The intelligence built into each component of the network is extended network-wide and applies end-to-end.
• Active participation of the network in the delivery of services and applications: With added intelligence, IIN makes it possible for the network to actively manage, monitor, and optimize service and application delivery across the entire IT environment.

IIN offers much more than basic connectivity, bandwidth for users, and access to applications. It offers end-to-end functionality and centralized, unified control that promotes true business transparency and agility. The IIN technology vision offers an evolutionary approach that consists of three phases in which functionality can be added to the infrastructure as required.

• Integrated transport: All traffic—data, voice, and video—consolidates onto an IP network for secure network convergence. By integrating data, voice, and video transport into a single, standards-based, modular network, organizations can simplify network management and generate enterprise-wide efficiencies. Network convergence also lays the foundation for a new class of IP-enabled applications delivered through Cisco IP Communications solutions.
• Integrated services: After the network infrastructure has been converged, IT resources can be pooled and shared or “virtualized” to flexibly address the changing needs of the organization. Integrated services help unify common elements, such as storage and data center server capacity. By extending virtualization capabilities to encompass server, storage, and network elements, an organization can transparently use all its resources more efficiently. Business continuity is also enhanced because shared resources across the IIN provide services in the event of a local system failure.
• Integrated applications: With Application-Oriented Networking (AON) technology, Cisco has entered the third phase of building the IIN. This phase focuses on making the network “application-aware” so that it can optimize application performance and deliver networked applications to users more efficiently. In addition to capabilities such as content caching, load balancing, and application-level security, Cisco AON makes it possible for the network to simplify the application infrastructure by integrating intelligent application message handling, optimization, and security into the existing network.

Using IIN, Cisco is helping organizations address new IT challenges, such as the deployment of service-oriented architectures (SOA), Web services, and virtualization. Cisco Service-Oriented Network Architecture (SONA) is a framework that guides the evolution of enterprise networks to an IIN. SONA provides the following advantages to enterprises:

• Outlines the path toward the IIN
• Illustrates how to build integrated systems across a fully converged IIN
• Improves flexibility and increases efficiency, which results in optimized applications, processes, and resources

Cisco SONA uses the extensive product line services, proven architectures, and experience of Cisco and its partners to help enterprises achieve their business goals. The Cisco SONA framework shows how integrated systems can allow a dynamic, flexible architecture, and provide for operational efficiency through standardization and virtualization. It brings forth the notion that the network is the common element that connects and enables all components of the IT infrastructure. Cisco SONA outlines these three layers of the IIN:

• Network infrastructure layer: Interconnects all IT resources across a converged network foundation. The IT resources include servers, storage, and clients. The network infrastructure layer represents how these resources exist in different places in the network, including the campus, branch, data center, WAN and Metropolitan Area Network (MAN), and teleworker. The objective for customers in this layer is to have anywhere and anytime connectivity.
• Interactive services layer: Enables efficient allocation of resources to applications and business processes that are delivered through the networked infrastructure. This layer comprises these services:
  • Voice and collaboration
  • Mobility
  • Security and identity
  • Storage
  • Computer
  • Application networking
  • Network infrastructure virtualization
  • Services management
  • Adaptive management
• Application layer: Includes business applications and collaboration applications. The objective for customers in this layer is to meet business requirements and achieve efficiencies by leveraging the interactive services layer.

---

Content 1.1 Introducing Campus Networks 1.1.2 Cisco Network Models Cisco provides the enterprise-wide systems architecture that helps companies protect, optimize, and grow the infrastructure that supports their business processes. The architecture integrates the entire network—campus, data center, WAN, branches, and teleworkers—offering staff secure access to the tools, processes, and services. Cisco provides the following network models with Cisco Enterprise Architecture:

• Campus architecture: Combines a core infrastructure of intelligent switching and routing with tightly integrated productivity-enhancing technologies, including IP Communications, mobility, and advanced security. The architecture provides the enterprise with high availability through a resilient multilayer design, redundant hardware and software features, and automatic procedures for reconfiguring network paths when failures occur. Multicast provides optimized bandwidth consumption, and quality of service (QoS) prevents oversubscription to ensure that real-time traffic, such as voice and video or critical data, is not dropped or delayed. Integrated security protects against and mitigates the impact of worms, viruses, and other attacks on the network, even at the port level. Cisco enterprise-wide architecture extends support for standards, such as 802.1x and Extensible Authentication Protocol (EAP). It also provides the flexibility to add IP Security (IPSec) and Multiprotocol Label Switching (MPLS) Virtual Private Networks (VPNs), identity and access management, and VLANs to compartmentalize access. This helps improve performance and security and decreases costs. The enterprise campus architecture will be the focus of this course.
• Data center architecture: Cohesive, adaptive network architecture that supports the requirements for consolidation, business continuance, and security while enabling emerging SOAs, virtualization, and on-demand