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Foundation Summary 31
Design Models
Advantages
Disadvantages
Full mesh
Maximum scalability
Maximum adaptability
Redundancy
Higher cost
As the network grows,
administration requirements
increase significantly.
Partial mesh
An effective solution, striking a balance
between scalability, adaptability, and cost
Some circuits might not be
protected with redundancy.
Three-tier model
Scalability
Ease of troubleshooting
Ease of administration and management
Model might be too costly for a
small network.
Table 1-3
Hierarchical Model
Hierarchical Model Layer
Functions
Core
High-speed transport layer between geographically remote sites
Distribution
Connects multiple networks within a network environment.
Establishes route filtering, route summarization, and network policy.
Provides network naming and numbering conventions.
Provides network security.
Access
Connects a LAN or a group of LANs. Gives users access to network
services.
Provides network segmentations.
Isolates broadcast traffic.
Distributes services.
Table 1-4
Recommended Equipment for Hierarchical Design
Layer
Recommended Equipment
Core
Cisco 7000, 12000 series
Distribution
Cisco 3600, 4000, 5000 series
Access
Cisco 1000, 1600, 2500 series
Table 1-2
Design Models (Continued)
87200333.book Page 31 Wednesday, August 22, 2001 2:18 PM