# A Comprehensive Survey on Knowledge-Defined Networking
## 8 Discussion
### Ongoing Research  
There are ongoing research efforts to standardize KDNs, specifically, to introduce new protocols, languages, and interfaces for KDN to make it more interoperable.  
IEEE P2302-2021 Standard for Intercloud Interoperability and Federation (SIIF) provides a reference architecture and taxonomy framework for enabling interoperability and federation between different cloud computing environments, which does not directly address knowledge-defined networking but covers a number of areas relevant to KDN [570]. This standard covers areas related to KDN such as interoperability between different cloud environments, security standards, a framework for orchestrating services across different cloud environments, the governance required for intercloud communication, and a taxonomy for describing different types of cloud services and environments. To achieve semantic interoperability between IoT frameworks, recent efforts such as IEEE P2413-2019 Standard for an Architectural Framework for the Internet of Things (IoT) have produced a report for IoT Semantic Interoperability. These efforts standardize ontologies for internet-of-things-based systems, such as domain ontologies, task ontologies, and user ontologies [571, 572]. A formal explanation of the connections and concepts in a particular field is called an ontology. Semantic interoperability is the capacity of various devices and systems to interchange information and comprehend one another's meaning, even when they speak different languages or have distinct vocabularies. KDN relies heavily on ontologies because they offer a structured representation of information that can be used to analyze network activity and make choices. Diverse bits of knowledge may be integrated by creating a coherent ontology.  
The Open Network Foundation (ONF) stratum project aims to enable programability, automation, and innovation in network infrastructure, which aligns with the goals of KDN [573]. The stratum project is focused on developing an open-source, silicon-independent switch operating system that enables hardware and software disaggregation in network switches.  
Metro Ethernet Forum (MEF) Lifecycle Service Orchestration (LSO) Sonata is a set of standards developed to standardize the way in which network services are orchestrated across multiple service providers and network domains. The MEF LSO Sonata attempts to standardize KDN by defining a set of APIs and data models that enable the exchange of information between different service providers and domains, which includes the use of standardized data formats such as YANG models and JSON, to represent network services and their attributes [574].  
The International Telecommunication Union--Telecommunication Standardization Sector (ITU-T) study Group 13 is working on standardization for Next Generation Networks (NGNs), network virtualization of Future Networks (FNs), cloud computing, and the Internet of Things (IoT) [575]. Even though this group does not specifically focus on researching KDN, it develops standards for SDN and NFV and develops interfaces between network components in NGNs, which include KDNs.  
Table 10 summarizes details of ongoing research related to the standardization of KDN.  
\begin{table}
\begin{tabular}{p{113.8 pt} p{113.8 pt} p{113.8 pt} p{113.8 pt}} \hline \hline
**Name** & **Research Area** & **Organization** & **Site Address** \\ \hline IEEE P2302 SIIF: Reference architecture and taxonomy framework & Interoperability, security, service orchestration, governance, and taxonomy for different types of cloud frameworks and environments & IEEE & [[https://standards.ieee.org/ieee/2302/7056/](https://standards.ieee.org/ieee/2302/7056/)]([https://standards.ieee.org/ieee/2302/7056/](https://standards.ieee.org/ieee/2302/7056/)) (accessed on 7 April 2023) \\ \hline IEEE P2413 Standard for an Architectural Framework for the Internet of Things (IoT)