  In cloud computing, software-defined network (SDN) gaining more attention due
to its advantages in network configuration to improve network performance and
network monitoring. SDN addresses an issue of static architecture in
traditional networks by allowing centralised control of a network system. SDN
contains centralised network intelligence module which separates a process of
forwarding packets (data plane) from packet routing process (control plane). It
is essential to ensure the correctness of SDN due to secure data transmitting
in it. In this paper. Model-checking is chosen to verify an SDN network. The
Computation Tree Logic (CTL) and Linear Temporal Logic (LTL) used as a
specification to express properties of an SDN. Then complete SDN structure is
defined formally along with its Kripke structure. Finally, temporal properties
are analysed against the SDN Kripke model to assure the properties of SDN is
correct.
