NST 2007 Extended Summary Proceedings of Engineering and Technology Innovation, vol. 5, 2017, pp. 07 - 12 The Design and Implementation of Scrambling Wavelength Hopping with AWG Router and Optical Switch over Secure WDM Network Yao-Tang Chang 1,* , Hsu-Chih Cheng 2 , Yih-Chuan Lin 3 , Yu-Xiang Zheng 2 1 Department of Information Technology Kao Yuan University Kaohsiung, Taiwan . 2 Department of Electro-Optical Engineering, National Formosa University, Yunlin, Taiwan . 3 Department of Computer Science and Information Engineering, National Formosa University, Yunlin, Taiwan. Received 26 July 2017; received in revised form 13 August 2017; accept ed 17 August 2017 Abstract In current e xperimental design, by e xchanging the optical switch configured in front of arrayed waveguide grating (AWG) router, the wave length hopping configuration was imple mented over wavelength division mu ltip le xing (W DM) network. In addit ion, in order to enhance the variab le wavelength hopping pattern of proposed scheme, the transceiver oscillators were used to trigger the optical switch by a series of random and un - predictable electrical signal. The e xpe riment results proved possible solution of secure WDM network that the wavelength hopping effect was monitored by optical spectrum analyze r (OSA) in optical do main. By u sing the oscilloscope for monitoring, the results showed the transmitted analogy signal of 10M Hzwas e xtracted correct ly by photo-detector while the wavelength hopping is happened. Ke ywor ds: a rrayed waveguide grating, wave length hopping, wavelength division mu ltiple xing, optical switch, photo-detector 1. Introduction Improving the confidentiality of access networks has emerged as a crit ical p roble m in recent years. It has been shown that optical code-division multip le-access (OCDMA) schemes significantly improve the robustness of optical networks toward ma lic ious attack [1-8]. Gene rally speaking in confidentia l topic, the WDM network was vie wed as without capability against eavesdroppers’ attacking. In order to achieve the confidential ability in wavelengt h division multip le xing (WDM) network, the a rrayed waveguide grating -based (AWG-based) wavelength hopping was presented by one of current authors [9-10]. Unfortunately, the proposed scheme had never been imp le mented in e xpe riment stage. Here, the possible and feasible configuration was demonstrated in wired W DM network to achieve similarly security mechanism of frequency hopping in wireless communications such as those executed over WiFi network. 2. System Architecture and Principles In current e xperimental design, the proposed of wavelength hopping configuration for scra mbling modulated signal was shown in Fig. 1. For co mmerc ia l components in practical e xperiment, the 8×8 AW G router and 2× 2 optical switch were e xploited. Actually, the only one input port of optical switch was applied and then below-mentioned optical switch could be called 1×2 optical switch. The SLD light source was applied to prov ide the three wave lengths of λ1=1556.3n m, λ2=1557.1n m, and λ8=1562.1n m, respectively. Connecting after the SLD light source, the 1×2 optica l switch which triggered by transmitted oscillator was * Corresponding author. E-mail address: t10066@cc.kyu.edu.tw Tel.: +886-7-6077138; Fax: +886-7-6077959 Proceedings of Engineering and Technology Innovation, vol. 5, 2017, pp. 07 - 12 Copyright © TAETI 8 used to exchange the optical path to enter arbitrary input port of AW G router (e.g., port #1 – #8 as seen in Fig. 1) wh ile cros s (on) and bar (off) state was happened. By emp loying inherent cyclic and FSR property of AWG router, the AWG router enables realizing N×N routers, in which N input wavelengths (#1 – #N) were de-multiplexed to N output ports. Fig. 1 The proposed wavelength hopping configuration using AWG router and optical switch on the transmitter Here, the different wavelengths appear in the output port of AWG router as user’s carrier and transfer to electro -optics modulator (EOM). The individual wave length carrier was modulated by the analog signal of 10M Hz for each user and coupled into fiber to received end. Finally, the wavelength hopping phenomenon of modulated signal was monitored by optical spectrum analy zer (OSA) and achieved the varying analog signal of 10MHz co ming fro m the diffe rent FG# 1(User #1) and FG#2(User#2). Following the cyclic property of AWG, the path of laser source was changed by optical switch fro m bar (off) to cross (on) state and entered into the different input port of AW G. Hence, the various wavelengths were appeared in origina l output port of AWG to create the wavelength changing. For changing the wavelength carrier o f each user, each user corresponded to perform wave length hopping and then protect ed against the un-authorized attacking. In addit ion, in order to enhance the variable wavelength hopping pattern of proposed scheme, the optical switch could be triggered by transceiver oscillators creating from a series of random and aperiodic electrical signal. In current practical e xperiment, the wavelength hopping of FG#1(User#1) was created fro m λ1=1556.3n m to λ8=1562.1n m while the optical switch state was converted by transmitter oscillator fro m bar to cross state. Simu ltaneously, the wavelength hopping of FG # 2(User #2) was created fro m λ2=1557.1n m to λ1=1556.3n m wh ile the optical switch state was converted by transmitter oscillator from bar to cross state. Fig. 2 The proposed wavelength hopping configuration using AWG router and optical switch and on the receiver Proceedings of Engineering and Technology Innovation, vol. 5, 2017, pp. 07 - 12 Copyright © TAETI 9 On the receiver shown in Fig. 2, the 1× 2 optical switch was trigged by received oscillator which had the same frequency as transmitter and decided the state of switch off (bar) or switch on (c ross), depending on transmitted end. Finally, the diffe rent optical signals appearing in the output port of AWG router were detected through photo-detector to retrieve the diffe rent analog signal fro m FG#1(User #1) and FG# 2(User#2). The oscilloscope (OSC) connected the photo-detector to observe the optical signal modulated by analog signal of 10MHz. 3. Experimental Result In current e xperiment, all the type and specification of using components is summarized in Table 1. In order to guarantee the imp le mentation of wavelength hopping correctly, the monitoring architecture configured with optical spectrum analyzer (OSA) and os cilloscope (OSC) was shown as Fig . 3 on the transmitter. He re, the OSA was used to measure the wavelength hopping happening when the optical switch was triggered by specific sequence (i.e., hopping pattern). Simu ltaneously, the OSC was used to measure the analog signal of 10MHz when the a mplitude of desired signal was retrieved by photo-detector from the specific wavelength. Fig. 3 The monitoring arch itecture configured with optical spectrum analy zer (OSA) and oscilloscope (OSC) on the transmitter There were two states of optical switch to be imple mented in Fig. 1. The bar (off) and cross (on) of 1× 2 optical switch were designed to verify the wavelengths hopping phenomenon, respectively. Table 1 All the type and specification of using components in current experiment Production Specification Transmitter Laser source NXTAR SLD-2200 Optical switch New Port SPSN-9-22-FCAPC AWG DWDM-G-100G-8-8-FC-APC Analog signal(10MHz/1MHz) Twintex TFG-3510 EOM Lucent ZX86-12G-S+ Coupler CP-S-A-2x2-1550-50/ 50-900-1-1-3x54mm-FC/ UPC Fiber FC/UPC-FC/APC-SM-SX-0.9mm-3M Receiver Optical switch Thorlabs GmbH OSW22-1310E AWG DWDM-G-100G-8-8-FC-APC Photo-detector New Focus model 1611 Measuring equipment optical spectrum analyzer (OSA) ANRITSU MS9710C Oscilloscope (OSC) Tektronix TDS2012B Proceedings of Engineering and Technology Innovation, vol. 5, 2017, pp. 07 - 12 Copyright © TAETI 10 Fig. 4(a) and Fig. 5(a) presented the wavelength spectra on the switch bar (off) state to focus only on the output port #1 and #2 of AW G router. The λ1=1556.3n m, λ2=1557.1n m and λ8=1562.1n m entered into the input port #1 of AW G router and appeared a pair of (output port #1, output port #2) wavelengths corresponding to (λ1=1556.3n m, λ2=1557.1n m). Actually, the wavelength of λ8=1562.1nm appear in the input port #8 of AWG router. (a) λ1=1556.3n m on the switch bar (off) state (b) λ8=1562.1nm on the switch cross (on) state Fig. 4 Appearing wavelength in output port #1 of AWG router Similarly, as seen from Fig. 4(b) and Fig. 5(b ), converting to the switch cross (on) state, the same wavelength of SLD changed the entrance into the input port #2 of AWG router and appear a pa ir of (output port #1, output port #2) wavelengths corresponding to (λ8=1562.1n m, λ1=1556.3n m). Actually, the wave length of λ2=1557.1n m appear in the input port #2 of AWG router. By mon itoring the switch changing fro m bar (off) to cross (on) state, the wavelength hopping of FG# 1(User#1) was imple mented fro m λ1=1556.3n m to λ 8=1562.1n m. Similarly, the wavelength hopping of FG# 2(User#2) was imp le mented from λ2=1557.1n m to λ1=1556.3nm. (a) λ2=1557.1n m on the switch bar (off) state (b) λ1=1556.3nm on the switch cross (on) state Fig. 5 Appearing wavelength in output port #2 of AWG router By measuring the appearing output port #1 of AWG router modulated by EOM #1, Figure 6 presented the different wavelengths as carriers which were modulated by the analog signal of 10MHz on the switch bar (o ff) state or cross (on) state. The oscilloscope (OSC) showed that the individual optical signal could be modulated by the analog signal through electro- optics modulator (EOM) to make the wavelength hopping possible. Similarly, by measuring the appearing output port #2 of AWG router modulated by EOM #2 , the Figure 7 presented the different wavelengths as carriers which were modulated by the analog signal of 10MHz. Proceedings of Engineering and Technology Innovation, vol. 5, 2017, pp. 07 - 12 Copyright © TAETI 11 (a). λ1=1556.3n m on the switch bar (off) state (b) λ8=1562.1nm on the switch cross (on) state Fig. 6 The modulated analog signal of 10MHz appearing in output port #1 of AWG router (a) λ2=1557.1n m on the switch bar (off) state (b) λ1=1556.3nmon the switch cross (on) state Fig. 7 The modulated analog signal of 10MHz appearing in output port #2 of AWG router 4. Conclusion In current study, the possible configuration in the wavelength hopping was experimented to achieve the secure modulated analog signal of 10MHz by electrical/optical modulator. The e xperiment results proved possible solution of secure WDM network that the wavelength hopping effect was monitored by optical spectrum analy zer (OSA) in optical domain. In addition, by using the oscilloscope (OSC) for monitoring the original signal, the results showed the transmitted analog signal of 10MHz was e xtracted successfully by photo -detector while the wavelength hopping was happened. In near future works, by replac ing 10M Hz analo g signal with video strea m, the desired converting interface of video and binary data bit (i.e ., e ither bit 0 or 1) will be installed. The e xperiment will be investigated to extract and recovery the video signal correctly. Furthermore , a secure wavelength hopping scheme will be imp le mented and verified to apply in mult imedia application. Acknowledgment This study was supported under grant Nos. MOST 105-2221-E-244-004 and MOST 104-2221-E-150-043. References [1] T. H. Shake, “Security performance of optical CDMA against eavesdropping,” Journal of Lightwave Technology, vol. 23, no. 2, pp. 655-670, February 2005. [2] T. H. 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