## 3 Related Work  
The main goal of this research work was to allow scientific applications to dynamically program the networks for bulk data transfer. It provided high performance, scalable, end-to-end, and programmable networks and enables scientific applications to use the network most efficiently. We utilized the advanced features of SDN technology for the capability of dynamic program [19, 20] networks and provided end-to-end QoS-guaranteed network service for scientific applications. In recent, there are a number of studies that have proposed similar goals. In this section, we reviewed the related work and provided the key differences between previous works and our proposed solution. A dynamic flow scheduling system, called Hedera, was proposed by in [21]. Hedera can reduce traffic collisions by using the adaptive scheduled switching fabric technique. Such a solution has been adopted in the PortLand testbed [22]. It is claimed that Hedera is able to manage the modest control and computation overheads, and more over increases the overall bandwidth up to four times higher than the conventional ECMP technique. The core design technology proposed in Hedera was based on a multi-root network topology tree, which uses the large number of parallel path between two edge switches. However, Hedera network architecture is not adoptable for Science DMZ networks because of its multi-root tree network, which creates the overhead of a large number of parallel path between two ends. [PERSON] et al. [23] achieved the considerably lower processing overhead by installing the wildcard packet handling rules using OpenFlow. Such an approach uses the technique of load balancing at each replica of servers. There are several approached can been found in [24] to reduce the overall  
Figure 3: AmoebaNet service along with BigData express architecture. cost associated with the OpenFlow's fine-grained control. In [25], research work helps to improve SDN scalability. To achieve the current traffic demands, SWAN [26] proposes a novel link utilization technique for inter data center networking. In this research, the author employed SDN technology to a re-configuration of data plane to match the traffic needs of applications. Google's B4 [27] proposed a similar type of solution, which addresses the problem of traffic engineering. To achieve the demands of applications, B4 splits the traffic flows into multiple paths to balance the load of applications as per given priorities. A single domain design architecture has been proposed in both B4 and SWAN solutions. Both are using a centralized SDN controller server to orchestrate all activities. However, the multi-domain problems have not been addressed in B4 and SWAN, which is an essential demand of scientific networks. In contrast, our proposed AmoebaNet solution complements the current network architecture (i.e., ESNet OSCARS) and provides complete integration services to support large scale data transfer services for multi-domain scientific centers. SDN security is one of hottest research topics. There are many research works for SDN security issues [28; 29; 30; 31]. Such security was out of our research scope, which is expected to be covered in our future work. The recent invention in SDN technology is P4 programming language, which has been proposed by the founder of SDN [32]. P4 is different from OpenFlow protocol; it has been designed to program and control the pipeline level of the data plane of SDN enabled routers and switches. The advent of P4 programming language introduced the new form of flexibility for users to control the network with a top-down approach [33; 34; 35; 36]. To provide the high performance end-to-end networking service for extreme-scale distributed science, we need to combine the concepts of DTNs and Science DMZs, emerging software-defined networking technologies and terabit wide area networks. The pacific research platform (PRP) [37] is an example of providing such type of network environments.