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a low network efficiency, and a long processing latency for end-to-end
path provisioning. erefore, a UCP for both IP and optical layers,
as one of the key challenges for network carriers, is very important to
address the aforementioned issues. GMPLS, with a decade of devel-
opment and standardization work, is a mature control plane technique
for optical transport networks. However, GMPLS-based UCP for
IP/DWDM multilayer networks is overly complex for deployment
in a real operational scenario. In this context, some studies concluded
that GMPLS has devolved from being a UCP to one that is meant
only as a control plane for optical transport networks [47]. On the
other hand, OpenFlow has been verified ...