TITLE:
Dynamic Capacity Allocation in OTN Networks
AUTHORS:
Maria Catarina Taful, João Pires
KEYWORDS:
OTN, VCAT, LCAS, Time Delay, Network Protection
JOURNAL NAME:
Communications and Network,
Vol.7 No.1,
February
15,
2015
ABSTRACT: A dynamic Optical Transport Network (OTN)
has the advantage of being able to adjust the connection capacity on demand in
order to respond to variations on traffic patterns or to network failures. This
feature has the potential to reduce operational costs and at the same time to
optimize networks resources. Virtual Concatenation (VCAT) and Link Capacity
Adjustment Scheme (LCAS) are two techniques that when properly combined can be
used to provide improved dynamism in OTN networks. These techniques have been
previously standardized in the context of Next Generation SDH/SONET networks.
VCAT is used to tailor the capacity of network connections according to service
requirements, while LCAS can adjust dynamically that capacity in a hitless
manner. This paper presents an overview of the application of VCAT/LCAS
techniques in the context of OTN. It explains in detail how these techniques
can be employed to resize the connection capacity and analyses its use in
network protection solutions. Furthermore, a detailed analysis of the time
delays associated with different operations is provided and its application to
some reference networks is undertaken. The obtained results provide an idea
about the time delays of the capacity adjustment processes and define potential
scenarios for implementing VCAT/LCAS techniques.