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.The other router acts as the hot standby router.In HSRP, a default IP address and a default MAC address are shared between the two routers exchanging the HSRP protocol.This default IP address is used as the default gateway at all IP end stations for them to communicate with end stations outsidetheir immediate subnet.Therefore, when there is a primary router failure, the hot standby router takes over the default gatewayaddress and the MAC address so that the end station can continue communicating with end stations that are not in theirhttp://www.cisco.com/cpress/cc/td/cpress/ccie/ndcs798/nd2008.htm (25 of 38) [9/16/2000 5:09:34 PM] Designing ATM Internetworksimmediate subnet.Because HSRP is a Layer 2 mechanism and needs a MAC address-based Layer 2 network, it is possible to implement HSRPstyle recovery over LANE.The mechanisms used are the same as for any Ethernet interface and can be configured at asubinterface level.Redundant ATM Port Card for the Catalyst 5000Another aspect of addressing the redundancy needs from a physical network perspective is the addition of a redundant PHYportion of an ATM card.The Catalyst 5000 switch employs the dual PHY redundant ATM card.This redundancy is only at aphysical level and is useful in cases where the primary link to the ATM switch goes down.Role of Stratm TechnologyStratm Technology is a new approach to ATM switching technology that incorporates patented standards-based Ciscotechnology into custom silicon.These application-specific integrated circuits (ASICs) dramatically increase ATM efficiencyand scalability and significantly lower the absolute cost of delivering ATM solutions.Stratm Technology can be implementedin switches and routers across LANs, campus networks, and WANs, enabling the delivery of high-performance, end-to-endATM services to meet a wide range of needs.Benefits of Stratm TechnologyThe benefits of Stratm Technology include the following:Dramatic improvement in network price/performance scalabilityIncreased application goodputProtection of technology investmentsIncreased portabilityGuaranteed infrastructureEach of these benefits is described in more detail in the following sections.Improved Network Price/Performance ScalabilityStratm Technology features can dramatically improve network price/performance and scalability as follows:Support of up to eight OC-3 (155-Mbps) port interfaces per card slot, and up to 12 digital signal Level 3 T3/E3(45-Mbps) port interfaces per card slotA 30 percent increase in SVC completions to more than 4,000 per second per nodeAn increase in connection density per switch by 500 percentAn increase in the buffering capability of each card to 200,000 cells per card, upgradable to nearly one million cellsA reduction in the price per port for high-speed connections by up to 50 percentThe ability to support per-virtual-connection control queuing, rate scheduling, statistics collection, and fair sharing ofnetwork resources on an individual connection basisIncreased Application GoodputIntelligent ATM features are embodied in Stratm Technology.These features are designed to increase application goodputdramatically through advanced features, which are distributed throughout the BXM module in silicon.Distributed ATM functions---Stratm distributes such ATM services as traffic management, per-VC queuing, class ofservice (COS) management, SVCs, and multicasting to each card on a silicon chip.Distributed functionality ensuresfaster, more efficient processing, and it eliminates the possibility of a single point of failure disrupting the entirenetwork.Highest bandwidth efficiency---Stratm delivers guaranteed bandwidth on demand, QoS, and fair sharing of networkresources to each individual connection.With fast, efficient processing and guaranteed bandwidth, applicationhttp://www.cisco.com/cpress/cc/td/cpress/ccie/ndcs798/nd2008.htm (26 of 38) [9/16/2000 5:09:34 PM] Designing ATM Internetworksperformance is significantly enhanced.Advanced traffic management capabilities---Stratm incorporates the industry's first commercially available VirtualSource/Virtual Destination (VS/VD) implementation of the full ATM Forum's Traffic Management SpecificationVersion 4.This ensures the highest efficiency in bandwidth utilization and provides support for the multicastingcapabilities required to successfully deliver multimedia and switched internetworking services.End-to-end intelligence---With VS/VD implementation, Stratm also represents the industry's first completeLAN-to-WAN ARB implementation.This feature enables ATM services to be delivered to the desktop, ensuring highperformance for the most demanding applications.Industry-Leading Investment ProtectionStratm allows you to protect your current investments by integrating with today's network infrastructures, and providingadvanced features and functionality to protect investments far into the future.You can protect your technology investmentbecause of the following Stratm capabilities:Seamlessly integrates with existing switches---Stratm Technology integrates into Cisco's ATM switching platforms,allowing you to enhance your investment in Cisco technology.Delivers unparalleled performance---Current ATM switching platforms deliver performance that enables end-to-enddelivery of high-quality, high-performance network services.Delivers the future---Stratm Technology extends the features and functionality of current switches to support nextgeneration requirements.With this technology, you can easily deliver multiple services from a single networkinfrastructure and ensure the highest QoS possible.Increases Portability and Guarantees an InfrastructureWith a modular chip set, Stratm increases the portability of standards-based ATM
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