Software Defined Networking (SDN) is a new network paradigm to simplify the networks and ease the network setup and management. Providing Quality of Services (QoS) in SDN, like in traditional networks is also important and attracts many attentions. Currently many researches propose some novel algorithms to provide QoS in SDN networks, but they usually focus on a single path. As we know, Multipath can provide some benefits, such as bandwidth aggregation, better network availability and reliability. Thus, this thesis first implements the mechanism proposed by M.A. Salahuddin to provide multipath SDN networks. The mechanism supporting multipath in SDN networks is not similar to that in traditional networks, due to the specific network architecture and routing mechanism that a SDN network has. Multipath in SDN networks is enabled by the use of a group table. Then this thesis implements Hierarchical Token Bucket (HTB) which not only provides queue and rate limiting for resource reservation but also network slicing functionality to guarantee QoS. The SDN environment used will be tphe simulated from Mininet. HTB can be implemented to this simulated SDN network via Linux Traffic Control (Linux tc) which normally embedded inside Linux Kernel. This feature was enabled due to the OVS (Open Virtual Switch) used by mininet is running over the same Linux architecture. Beside Linux tc, there is another method which is ovs-vsctl but Linux tc is more recommended to use. There are several things need to be concern in the implementation of HTB in the multipath SDN environment, such as the selection SDN component such as controller type, and Openflow version. The reason that HTB is selected as the mechanism to guarantee QoS is because HTB can give fine control over the network slicing with its multiclass queue. Together with HTB filter, HTB can give a specific classification for every network service and packets to support the network virtualization. Experiment results show that HTB can guarantee and limit the rate for each service in multipath SDN network. Therefore, by implementing HTB in multipath SDN environment, the QoS can be guaranteed.

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