A channel-growth plan for an optical transmission system selects channels
such that the transients that result in the channels that survive a
network failure, such as an upstream fiber cut, are either minimized or
effectively handled by some transient-control technique. In one
embodiment, the growth plan may try to keep post-transient surviving
channel total power gain equal to the pre-transient total power gain.
Alternatively, the growth plan may try to distribute the surviving
channels uniformly over the pre-transient channel-frequency range. Other
manifestations are to keep (1) the average power of the surviving
channels substantially equal to the average power of the pre-transient
channels or (2) the average power of the post-transient surviving
channels substantially equal to the power level of a specified channel.
Transient-control can be balanced with conventional low-cost and
high-performance goals to provide an effective hybrid channel-growth
plan.