Vehicle Ad-hoc Networks (VANETs) plays an essential role in enhancing
safety, passenger services, and traffic management. VANETs often suffer
from reliability issues and delays due to their dynamics. Multihoming,
where vehicles communicate over multiple networks, is a possible
approach to mitigate these problems. In this paper, we present a
comprehensive survey exploring the integration of multihoming with
Software-Defined Networking (SDN), Programming Protocol-independent
Packet Processors (P4), and Service Function Chaining (SFC) in VANETs, a
set of technologies that play an important role in modern computer
networks. To select the papers to be analyzed in our survey, we used a
four-stage process, starting on keyword searching and consisting of
multiple filtering and a final grouping step. This process resulted in
300 research papers from 2009 to 2023. Our analysis revealed the
importance of routing techniques tailored for dynamic VANET
environments, highlighting the critical challenge of delays resulting
from intermittent connectivity and rapid topology changes. To the best
of our knowledge, available literature does not consider the integration
of SDNs, P4, and SFC to improve connectivity in VANETs: some SDN
applications include VANETs support but previous research tends to
consider the use of P4 and SFC within data center contexts and security
applications. Since P4 can simplify traffic management, SFC can help
supporting services and policies, and technologies like MultiRadio
Access Technologies (M-RAT) can enable multihoming, the possibility of
using SDNs with these technologies to support multihoming in VANET lays
the foundation for future progress in vehicular communication systems.
This approach shows potential for new developments and challenges,
taking into account future trends and directions.