隨著智慧裝置的發展，現在的行動裝置皆具有與各種無線通訊連線的技術，如：WLAN、3G、WiMAX和LTE。使用者在異質網路間可以藉由多路徑傳輸（Multipath-TCP）來獲得可靠以及有效率的影音串流（video streaming）。有兩件事情是使用者想要的：第一，隨時隨地在服務與裝置上可以保持最佳的連線。第二，行動裝置可以持續的連線而且可以無縫換手到另一個網路上。
多路徑傳輸（Multipath-TCP）是TCP的延伸，它可以利用多界面來同時傳輸且支援使用者可以移動以及換手到另一個網路。但是，多路徑傳輸有吞吐量（throughput）以及電量損耗的問題。我們必須制定一個機制讓MPTCP可以被運用得更完善，因為同時使用多個界面來傳輸會消耗更多的電量。在這篇論文，我們提出一個動態多路徑傳輸控制機制，讓我們在不同網路之間可以無縫換手，而且當網路品質良好時，只使用一種網路服務。透過實作，此篇論文提出的演算法可以提升吞吐量以及節能（energy efficiency）。

Nowadays, with the evolution of smart devices, mobile nodes are commonly equipped with multiple communication interfaces, for example: WLAN, 3G, WiMAX and LTE. Users and network operators can benefit from multipath TCP to achieve more reliable and efficient video streaming in heterogeneous networks. Two things are the users need. First, it always keeps the best connection in services or devices anywhere at any time. Second, it keeps service continuous and seamless handover to another network interface.
Multi-path TCP (MPTCP) is an extension of TCP that allows multiple interfaces to transmit simultaneously. MPTCP can support mobility and handover, but MPTCP has throughput and energy consumption problems. We must make a decision to use MPTCP well. But using several interfaces at the same time would cost more energy consumption. In this thesis, we develop a dynamic MPTCP control mechanism to enable seamless vertical handover during network transition and use a single radio technology when stable. Through the implementation, it can improve throughput and energy efficiency.

[1] LTE-WiFi Aggregation. http://www.netmanias.com/
en/post/reports/8532/laa-lte-lte-u-lwa-mptcp/
analysis-of-lte-wifi-aggregation-solutions/.
[2] MultiPath TCP - Linux Kernel implementation. http://www.multipath-tcp.
org/.
[3] Network bandwidth requirements for media traffic in Lync Server 2013. https://
technet.microsoft.com/en-us/library/jj688118(v=ocs.15).aspx, 2013.
[4] Atiq Ahmed, Leila Merghem Boulahia, and Dominique Gaiti. Enabling vertical handover
decisions in heterogeneous wireless networks: A state-of-the-art and a classification.
IEEE Communications Surveys & Tutorials, 16(2):776–811, 2014.
[5] O Bonaventure. Decoupling TCP from IP with multipath TCP. http://
multipath-tcp.org/data/MultipathTCP-netsys.pdf/, 2013.
[6] Shengyang Chen, Zhenhui Yuan, and Gabriel-Miro Muntean. An energy-aware
multipath-tcp-based content delivery scheme in heterogeneous wireless networks. In
2013 IEEE Wireless Communications and Networking Conference (WCNC), pages
1291–1296. IEEE, 2013.
[7] Tao Ding, Zhenhui Yuan, Shengyang Chen, and Gabriel-Miro Muntean. Smartphone
energy consumption models for multimedia services using multipath tcp. In 2014
IEEE 11th Consumer Communications and Networking Conference (CCNC), pages
239–244. IEEE, 2014.
[8] Alan Ford, Costin Raiciu, Mark Handley, and Olivier Bonaventure. Tcp extensions
for multipath operation with multiple addresses. Technical report, 2013.
[9] Takoua Ghariani and Badii Jouaber. Energy aware cross layer uplink scheduling for
multihomed environments. In 2013 IEEE Globecom Workshops (GC Wkshps), pages
861–866. IEEE, 2013.
[10] Han Ah Kim, Bong-hwan Oh, and Jaiyong Lee. Improvement of mptcp performance
in heterogeneous network using packet scheduling mechanism. In 2012 18th Asia-
Pacific Conference on Communications (APCC), pages 842–847. IEEE, 2012.
[11] Ben Liang, Ahmed H Zahran, and Aladdin OM Saleh. Application signal threshold
adaptation for vertical handoff in heterogeneous wireless networks. In International
Conference on Research in Networking, pages 1193–1205. Springer, 2005.
[12] Yeon-sup Lim, Yung-Chih Chen, Erich M Nahum, Don Towsley, and Richard J
Gibbens. Improving energy efficiency of mptcp for mobile devices. arXiv preprint
arXiv:1406.4463, 2014.
[13] Yeon-sup Lim, Yung-Chih Chen, Erich M Nahum, Don Towsley, Richard J Gibbens,
and Emmanuel Cecchet. Design, implementation, and evaluation of energy-aware
multi-path tcp. CoNEXT15, 2015.
[14] Yeon-sup Lim, Yung-Chih Chen, Erich M Nahum, Don Towsley, and Kang-Won Lee.
Cross-layer path management in multi-path transport protocol for mobile devices.
In IEEE INFOCOM 2014-IEEE Conference on Computer Communications, pages
1815–1823. IEEE, 2014.
[15] Sinh Chung Nguyen, Xiaofei Zhang, Thi Mai Trang Nguyen, and Guy Pujolle. Evaluation
of throughput optimization and load sharing of multipath tcp in heterogeneous
networks. In 2011 Eighth International Conference on Wireless and Optical Communications
Networks, pages 1–5. IEEE, 2011.
[16] Christoph Paasch and Olivier Bonaventure. Multipath TCP. Communications of the
ACM, 57(4):51–57, apr 2014.
[17] Christoph Paasch, Gregory Detal, Fabien Duchene, Costin Raiciu, and Olivier
Bonaventure. Exploring mobile/wifi handover with multipath tcp. In Proceedings of
the 2012 ACM SIGCOMM workshop on Cellular networks: operations, challenges,
and future design, pages 31–36. ACM, 2012.
[18] Christopher Pluntke, Lars Eggert, and Niko Kiukkonen. Saving mobile device energy
with multipath tcp. In Proceedings of the sixth international workshop on MobiArch,
pages 1–6. ACM, 2011.
[19] Xiaohuan Yan, Y Ahmet S¸ekercio˘glu, and Sathya Narayanan. A survey of vertical
handover decision algorithms in fourth generation heterogeneous wireless networks.
Computer networks, 54(11):1848–1863, 2010.
[20] Ahmed H Zahran and Ben Liang. Performance evaluation framework for vertical
handoff algorithms in heterogeneous networks. In IEEE International Conference on
Communications, 2005. ICC 2005. 2005, volume 1, pages 173–178. IEEE, 2005.
[21] Ahmed H Zahran, Ben Liang, and Aladdin Saleh. Signal threshold adaptation for vertical
handoff in heterogeneous wireless networks. Mobile Networks and Applications,
11(4):625–640, 2006.