Carriers can also choose to set up protection routes dynamically, either after a failure has occurred or ahead of time for proactive rules setup. This intelligence comes at the cost of complexity, says Clavenna. Managing thousands of millions of lightpaths requires adding significant computing power within optical systems. This isn't a trivial undertaking and will likely take more time than most vendors anticipate. Chris Nicoll, an analyst with telecom consultancy Current Analysis , agrees.
Meshes require a high degree of intelligence that makes interoperation of networks very difficult.
Thus, multivendor network implementations usually require some sort of standards work to provide interoperation at the intelligence level. It makes sense to use mesh in any network, CLEC or RBOC, where there are fiber constraints because mesh networks make more efficient use of fiber resources, says Charlie Wang, Astral Point's senior product manager. The metro has scattered access points and generally cheaper bandwidth, which are best supported by rings. The bandwidth reservation issue is less in the metro, where bandwidth is cheaper, according to Nicoll, but it's a killer in the WAN, where bandwidths are much higher. Traffic type and access characteristics are significant too.