Internet Routing Architectures, Second Edition

Specific Scenarios: Designing Redundancy, Symmetry, and Load Balancing

By now you recognize the general ways in which the design goals of redundancy, symmetry, and load balancing intersect with and potentially conflict with one another. How is it possible to balance traffic among multiple links and still achieve a single entrance and exit point as symmetry mandates? This becomes even more difficult when multiple links are spread out over multiple routers in the autonomous system. The routing attributes described in Chapter 6 are the tools for implementing the desired redundancy, symmetry, and load balancing. It is the responsibility of the operator to choose and configure the correct attributes and filtering to achieve the desired outcome. ...