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 Internetworking  Campus Networks  Issues - nonhierarchical network  multilayer switches in nonhierarchical network  Enterprise Composite module (ECNM) ◦ benefits of the ECNM  Campus Infrastructure module of the ECNM 2RD-CSY3021

Typical Enterprise Network  Internetworking is the communication between two or more networks ◦ Requires many protocols and features to  permit scalability  manageability without constant manual intervention  Large internetworks can consist of the three distinct components: 1. Campus networks, which consist of locally connected users in a building or group of buildings 2. Wide-area networks (WANs), which connect campuses together 3. Remote connections, which link branch offices and single users (mobile users and/or telecommuters) to a local campus or the Internet 3RD-CSY3021

Campus Network  A campus is a building or group of buildings all connected into one enterprise network that consists of many local area networks (LANs). ◦ A large campus with groups of buildings can also use WAN technology to connect the buildings  Campus network generally optimized for the fastest functional architecture that runs on existing physical wire.  Scalable to requirements of emerging applications 4RD-CSY3021

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Trends: Past and PresentTrends in campus design Past:  Limited hardware options ◦ routers or hubs when purchasing a technology for their campus networks Recent:  deploying LAN switches to replace shared concentrator hubs and give higher bandwidth connections to the end user 6RD-CSY3021

DisadvantagesFlat Network  Large collision domain  Large broadcast domain  High latency  Difficult to troubleshoot 7RD-CSY3021

Issues  No traffic between VLANs  Unbounded broadcast domain  Servers not centrally located Features and IssuesSwitched Network  Features  Hardware-based bridging  Wire-speed performance  Collision domain per port  Traffic containment based on MAC address 8RD-CSY3021

Features and IssuesRouted Network   Single broadcast domain per interface  ACLs can be applied between segments Issues  High per-port cost  Layer 3 processing required  High latency over Layer 2 switching 9RD-CSY3021

 Combined functionality Layer 2 switching Layer 3 switching Layer 4 switching  Low latency  High-speed scalability 10RD-CSY3021

 Single point of failure for Layers 2 and Layers 3  Underutilization of hardware  Spanning tree complexity  Servers not centrally located 11RD-CSY3021

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 Multilayer switches combine both Layer 2 and Layer 3 functionality to support the modern campus network topology.  Multilayer switches can be used in nonhierarchical networks; however, they will not perform at the optimal level.  The enterprise composite model identifies the key components and logical design for a modern topology.  Implementation of an ECNM provides a secure, robust network with high availability.  The Campus infrastructure, as part of an ECNM, provides additional security and high availability at all levels of the campus. 16RD-CSY3021

 Cisco Service-Oriented Network Architecture ◦ working_solutions_market_segment_solutions_hom e.html working_solutions_market_segment_solutions_hom e.html  Cisco Intelligent Information Network ◦ working_solutions_market_segment_solution.html working_solutions_market_segment_solution.html 17RD-CSY3021

 Designing LANs ◦ Routed Network  Compatibility,  conformance, and  Interoperability 18RD-CSY3021