Table 4-13 summarizes the survivability options discussed in this chapter. It can be seen from this table that network survivability techniques involve a multidimensional trade-off between restoration time, bandwidth efficiency, and failure robustness.
|Name||Restoration Time||Bandwidth Required||Failure Robustness|
|1+1 Linear (SDH/SONET)||Typically under 50 ms||2x||Only as good as the diversity of the alternative paths. Handles single failure.|
|1:N Linear (SDH/SONET)||Typically under 50 ms||Only as good as the diversity of the paths, Handles single failure.|
|Bi-directional Line Switched Ring (BLSR) Failures.||Typically under 100 ms||2x||Diversity built in, one line out, except in 4F case which can handle ...|