Specifications

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Cisco Nexus 3000 Series NX-OS Unicast Routing Configuration Guide, Release 5.0(3)U2(2)
OL-25782-02
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Overview
This chapter introduces the underlying concepts for Layer 3 unicast routing protocols in Cisco NX-OS.
This chapter includes the following sections:
• Information About Layer 3 Unicast Routing, page 1-1
• Routing Algorithms, page 1-8
• Layer 3 Virtualization, page 1-10
• Cisco NX-OS Fowarding Architecture, page 1-10
• Summary of Layer 3 Unicast Routing Features, page 1-12
• Related Topics, page 1-14
Information About Layer 3 Unicast Routing
Layer 3 unicast routing involves two basic activities: determining optimal routing paths and packet
switching. You can use routing algorithms to calculate the optimal path from the router to a destination.
This calculation depends on the algorithm selected, route metrics, and other considerations such as load
balancing and alternate path discovery.
This section includes the following topics:
• Routing Fundamentals, page 1-2
• Packet Switching, page 1-2
• Routing Metrics, page 1-3
• Router IDs, page 1-5
• Autonomous Systems, page 1-5
• Convergence, page 1-6
• Load Balancing and Equal Cost Multipath, page 1-6
• Route Redistribution, page 1-6
• Administrative Distance, page 1-7
• Stub Routing, page 1-7