Implementation of multipath network
virtualization scheme with SDN and NFV
QingtianWang, Junli Xue, Guochu Shou, Yaqiong Liu, Yihong Hu, Zhigang Guo
Beijing Key Laboratory of Network System Architecture and Convergence
School of Information and Communication Engineering
Beijing University of Posts and Telecommunications, Beijing 100876, China
{qtwang, junlixue, gcshou, liuyaqiong, yhhu, gzgang}@bupt.edu.cn
Abstract—Multipath algorithms except Equal-Cost
Multi-Path(ECMP) which has been widely used in
networks are difficult to apply, because multipath
provisioning is more complex at cross layers and
multipath routing need to get all nodes’ information. To
address the dilemma, this paper proposes a multipath
network virtualization implementation scheme with
Software Defined Networking (SDN) and Network
Function Virtualization (NFV). In this scheme, SDN
schedules network resources in a global view for selecting
multiple paths and computing weight of each path, and
NFV provides computing and storage resources to split
flow, add tag, recover flow, to name a few. This paper also
proposes a multipath algorithm for elephant flow with
network virtualization. Besides, we build an experimental
platform based on OPNFV and SDN, and conduct
experiments under this experimental platform. The
results show that our proposed algorithm applied on
multipath network virtualization experimental platform
has superior performance than ECMP applied in
networks without virtualization.
Keywords—multipath; virtualization; NFV; SDN;
elephant flow
I. INTRODUCTION
The new online applications, such as social
networking (e.g.,Twitter,Weibo), high definition video
streaming (e.g.,YouTube) and serious game propose a
new set of demands on throughput, bandwidth, Quality
of Service(QoS) and end-to-end delay. In present
Internet, most of communications are established over a
single path, which is easy to cause network constraints
(e.g., load unbalancing). Multiple paths no longer aim
only at solving problems from a single path but also
focus on ensuring high quality network services and
guaranteeing QoE (Quality of Experience) [1][2].
Multipath configurations can be established in several
different ways, [3] discusses five multipath cases in
different networks, such as multipath routing at source
node with multiple interfaces and multipath routing
over wireless mesh network or mobile ad hoc.
Equal-Cost Multi-Path (ECMP) is simple to deploy
in multipath routing, so it is widely used in present
network and it spreads the flow over multiple equal
cost paths using hash functions. Most of routing
protocols, such as Open Shortest Path First (OSPF) [4]
and Intermediate System to Intermediate System (IS-IS)
[5], support ECMP. Besides, some router
implementations also allow ECMP usage with Routing
Information Protocol (RIP). However, some algorithms,
such as FLARE [6], LBPF [7], LDM [8], which also
have good performances are not widely used. The main
reasons are that multipath provisioning is more
complex at higher layers than at the lower layers, and
network topological information need to be
disseminated to all nodes in multipath routing [3].
Network virtualization can abstract physical layer
resource to the virtual layer. Furthermore, the global
view of network resources will be formed in virtual
layer. The control layer manages network resources in
an effective way, thereby enhancing the network
resource utilization and avoiding complex signaling
mechanisms at cross layers. In [9]S.He et al. proposed a
viable way to establish multipath access in the FiWi
network through the flexible use of virtual networks
with network virtualization.
Software defined networking (SDN) is a network
paradigm that separates the control and data plane and
consolidates the control functions into controller. In
SDN paradigm, all control functions are concentrated
in the control plane, and controller manages network
through the global view of network. Recently, there are
lots of researches on multipath with SDN, such as [20]
[21] [22]. SDN has the ability to simplify network
design, so it is easy to deploy the new network
mechanism. It has been widely adopted as a means to
enable network virtualization [10]. However, network
devices could not provide lots of computing and
storage resources, so the emergence of Network
Function Virtualization (NFV) and SDN forms a
supplement.
NFV aims to address the dilemma of traditional
hardware-based network devices. Network functions
are softwarized and can be deployed dynamically on