PETRI NETS MODELING FOR SDN TOPOLOGIES

The article examines some new algorithms and focuses mainly on suggesting new working topologies for software-defined controllers in order to ensure SDN security and to prevent the occurrence of a potential central point of failure (SPOF) by overcoming the centralization problem. This is a positive feature of the SDN structure, but could also be a threat, caused by the use of several controllers in different working topologies. This article focuses on exactly one of the suggested topologies, which features and models based on the Petri Nets system. The usual topology of a single controller is compared to verify the advantages and privileges of the proposed serial topology over the existing one. The paper tries to obtain a formula from the modeling of the serial topology and its advantages over the usual topology and that formula will be used to measure the level of security or the defense capacity of the network defined by the software against cyber attacks; in particular, denial of service attacks / distributed denial of service attacks / DDoS.