Anomalous Behaviour of Cryptographic Elliptic Curves over Finite Field.
Elliptic curves have been studied as a mathematical concept since the second century A.C., while the name "elliptic" was given in the nineteenth century . However, the concept of Elliptic Curve Cryptography (ECC) has only been known about in the last 30 years. The first use of elliptic curves in cryptography was by H. W. Lenstra for elliptic curve factorization which was used as the fastest algorithm to find factors of large integers . However, N. Koblitz and V. Miller are considered as the founders of ECC. In 1985 N. Koblitz  and V. Miller  independently proposed the use of a group of points on an elliptic curve defined over a finite field. Over the past 30 years, ECC has become a key part of many current cryptosystems, cryptographic schemes and algorithms, e.g., Elliptic curve Diffie-Hellman (ECDH), Elliptic curve Integrated Encryption Scheme (ECIES), Elliptic curve Digital Signature Algorithm (ECDSA), Edwards-curve Digital Signature Algorithm (EdDSA), Elliptic curve Menezes-Qu-Vanstone (ECMQV), and Elliptic curve Qu-Vanstone (ECQV). ECC is also recommended in different standards, e.g., by Standards for Efficient Cryptography Group (SECG) in SEC1 , SEC2  and SEC4 ; by the National Institute of Standards and Technology (NIST) in 800-57  and FIPS 186-2 ; by Accredited Standards Committee X9 in ANSI X9.62  and ANSI X9.63 ; by Institute of Electrical and Electronics Engineers in IEEE 1363-2000 ; and by Wireless Application Forum in WTLS . Furthermore, many real implementations use and provide ECC primitives and algorithms, e.g., Bouncy castle , TinyECC  Crypto++ , OpenSSL , and FlexiProvider .
The main advantage of ECC is reaching the same level of security by using a smaller key compared to classical asymmetric cryptographic schemes based on factoring modulus or a discrete logarithm. This reduces such factors as memory storage requirements, key transmission time, arithmetic computation power costs and the bandwidth , . This key advantage is the reason why ECC is favoured in internet-based applications and preferred for constrained devices with low computational power and low memory storage, smart cards and cryptographic tokens. These constrained devices are portable, small, and lightweight and have low processing power, parameter storage and memory . These areas might be summarized as limited devices, which are defined mainly by their low computational power and low memory storage capacity. This paper deals with the research of new effective methods for speed and memory optimization of ECC used in limited devices. Many current methods deal with ECC optimization by finding new effective methods. These solutions are hard to deploy and often require main system changes. On the other hand, we try to provide a solution which is comparably effective as more complex methods, but very easy to deploy.
The rest of the paper is organized as follows. Section II summarizes related works. Section III introduces our experimental environment. Further, in Section IV the main experimental measurements of ECC are provided. The discussion and comparison with other works is provided in Section IV. Finally, Section V summarizes our conclusions.
II. Current and Related Work
Due to new wireless technologies and other worldwide technological changes and progresses made, the modern concept of The Internet of Things (IoT) is attracting more attention. IoT is based on connecting even the simplest sensors (limited devices) with each other as well as connecting these to the global network infrastructure . These connected devices have a wide use over many areas and should provide heightened amounts of information which might be used to increase the life quality of the citizens, ensure higher level of process automation, discover new options for optimization, general security purposes and even for saving lives in disasters . The wide use of connected devices and objects also gives rise to new challenges in the areas of architecture, availability, reliability, mobility, performance, management, scalability, interoperability, security and privacy . Basic security issues might be solved by encryption, authentication and authorization algorithms. However, due to the usage of limited devices, the implementation of these algorithms is a difficult task. ECC is nowadays used among others to solve these difficulties and it also provides secured solutions for limited devices .
Most of the current works that are focused on improving the efficiency of ECC algorithms are based on:
--developing new and more efficient algorithms i.e. for point multiplication -,
--creating new and more efficient curves ,
--using different unusual algorithms or more efficient mathematical fields forECC , .
In general, these methods are appropriate and they bring significant and efficient results, but they are also often very hard to deploy. However, if we take a closer look at the curve speed in different kinds of algorithms, methods and implementations, we can see significant speed differences even for curves of similar types. In the work  we showed our lightweight ECDH implementation with various curves, where curves of the same size had up to 50 % speed difference. Our previous work  already showed the differences between the efficiency of prime field based and field of characteristic 2 based elliptic curve systems in limited devices. The prime field based curves show a higher efficiency on limited devices than curves with field of characteristic 2 (by tens of percent). Based on these results we believe the efficiency might be improved not only with new algorithms or new curves, but also by choosing the right elliptic curve from the current ones. Our solution will be easier to deploy with similar effectiveness. Additionally, the in-depth research of current elliptic curves and their behaviour on specific limited hardware might also bring significant results for new algorithms or curves in the future.
This paper provides a new look at the efficiency of various cryptographic elliptic curves. We provide a clear description of elliptic curve parameterization. On this basis, we explain the links between computation speed and elliptic curve domain parameters. This new approach might be used for creating faster and memory friendly curves. Further, the experimental measurements which are showing the discovered anomalous behaviour of some elliptic curves are provided. This anomaly might be used for simple speed and memory optimization without additional needs.
III. Experimental Background and Pre-Sets
A. Network Model
We are developing a secure solution for the smart grid. Our network model helps us to develop solutions which might be rapidly implemented into real applications. The smart grid often uses limited devices i.e. for measuring consumption (water, gas, heat take-offs), failure states indicators, power quality monitors and many others. Fig. 1 shows our smart grid network model for this measurement where we can see the part with limited resources (limited devices) and also the part with non-limited resources.
The Intelligent Communication Unit is a limited device which connects even the simplest meters, sensors and indicators via a specific interface (i.e. PLC, RS485, USB) and communicate over access technology (i.e. PLC, Wireless) with a data concentrator. In this experiment, we consider a microcontroller MSP430 and a computer unit, the Raspberry Pi 2, for the non-limited area as a core of the communication unit for the limited area.
B. Experimental Measurements Pre-Sets
The MSP430 of the 5438A family is considered as a core for limited devices in our measurements. MSP430 is an ultra-low power micro-controller with power consumption in hundreds of [micro]A for the active mode and units of [micro]A for the standby/sleep mode. This microcontroller has 256 kB FLASH, 16 kB RAM, 32-bit multiplier, high/low frequency crystal (32 MHz/32 kHz) and allow 16-bit operations; more details about technical specification of MSP430 can be found in . For MSP430, we used our lightweight implementation of elliptic curve primitives and ECDH algorithm.
The Raspberry Pi 2B is considered in our measurements as a core for non-limited devices. We included this unit in our measurement to obtain more data. The Raspberry Pi 2B is a simple computer unit based on the Broadcom BCM2836 processor. This device has a 900 MHz quad-core ARM Cortex A7 processor and 1 GB LPDDR2 memory; more details about the technical specification of the Raspberry Pi 2B are in . For the Raspberry Pi 2B, we used the OpenSSL library which implements elliptic curve primitives, curves of different standards and many different algorithms based on elliptic curves i.e. ECDH or ECDSA.
C. Elliptic Curve Cryptography Implementations
Our light-weight solution is precisely described in  and it is available on . We have implemented more than 60 elliptic curves of different kinds of standards together with a big-number representation and basic and modular arithmetic. We use classical representation of elliptic curves by domain parameters which are pre-generated and defined by a standard. For point multiplication, the non-adjective form of multiplication w-NAF is used (Double-and-add variation, D&A) and Montgomery modular algorithms are used for other modulo operations. The operations are optimized for the low-power microcontroller MSP430 and ECDH algorithm.
The OpenSSL is a non-lightweight ready-to-use library for a wide range of applications. This solution brings all the necessities for implementing a system based on ECC. This library also contains all the necessities for the ECDH and ECDSA algorithms. A detailed description of this library is in  and it is available on .
IV. Impact of Elliptic Curve Domain Parameters on Speed Efficiency
Each elliptic curve is defined by the field and domain parameters. We will work with two different field types, field of characteristic 2 and prime field. The elliptic curves over finite field of characteristic 2 ([F.sub.2]m) have seven domain parameters (septuple)
[mathematical expression not reproducible] (1)
where m is an integer specifying [F.sub.2]m; f(x) is irreducible binary polynomial of degree m specifying the polynomial basis representation of [F.sub.2]m ; a, b are two elements of [F.sub.2]m (a, b [member of] [F.sub.2]m) specifying an elliptic curve E([F.sub.2]m) defined by
E: [y.sup.2] + xy = [x.sup.3] + [ax.sup.2] + b in [F.sub.2]m, (2)
where variable G is a base point G = ([x.sub.G], [y.sub.G]) on E([F.sub.2]m); prime n is order of G; and finally the integer h is the cofactor
h = # E ([F.sub.2]m)/n. (3)
The elliptic curves over finite prime field ([F.sub.p]) have six domain parameters (sextuple)
[mathematical expression not reproducible] (4)
where p is an integer specifying [F.sub.p]; a, b are two elements of [F.sub.p] (a, b [member of] [F.sub.p]) specifying an elliptic curve E([F.sub.p]) defined by
E: [y.sup.2] [equivalent to] [x.sup.3] + ax + b (mod p), (5)
where variable G is a base point G = ([x.sub.G], [y.sub.G]) on E([F.sub.p]); prime n is order of G; and finally the integer h is the cofactor
h = # E ([F.sub.p])/n. (6)
There are three main mathematical operations with elliptic curves (or their points): point addition, point doubling and point (scalar) multiplication. These operations are the basis for all other mathematical algorithms for ECC i.e. the ECDH and ECDSA algorithms. The time consumption and computational difficulty of these basic operations with points of elliptic curves is obviously curve-size dependent. This means operations with curves of larger domain parameters should be slower than operations with curves of smaller domain parameters.
We independently measured more than 60 elliptic curves on two different software implementations (own and OpenSSL implementation) and two different hardware devices (the MSP430 limited-device and the Raspberry Pi 2B non-limited device). The size of domain parameters for each measured elliptic curve is in Appendix A (Table A-I, A-II). Table I and II summarize our main experimental results where curve name is the official elliptic curve name defined by the standard SEC (sect/secp elliptic curves), WTLS (wtls elliptic curves), ANSI (prime, c2pnb/tnb elliptic curves) or IPSec (ipsec elliptic curves). Field defines the [2.sup.m] of [F.sub.2]m (or p of [F.sub.p]). No. is the number of significantly smaller domain parameters than degree m (i.e. curve wtls1 with field F114 has domain parameters [m.sub.114b], [a.sub.1b], [b.sub.1b], [x.sub.113b], [y.sub.112b], [n.sub.112b] the No. is 2, because of a, b). Parameter to is time needed for curve ECDH key and ECDH parameters generation with the specific curve. The At is defined as a time difference between the fastest curve and the concrete curve and it is given as a percent (value 0.00 mark the fastest curve), where [DELTA][t.sub.1] is measurement on Raspberry Pi 2B and [DELTA][t.sub.2] is on MSP430.
Table I shows the results for measured elliptic curves over the field of characteristic 2 on the Raspberry Pi 2B with OpenSSL implementation. The results are as expected and more samples or other measurements on different platforms are not necessary. The curves with a higher degree are generally slower. Further, the curves of the same degree with small domain parameters (a, b, x, y) are generally faster than curves with normal sized domain parameters (same size as curve degree). Some higher degree curves with small domain parameters (ipsec3, [??]) are even comparably as fast as lower degree curves with non-small domain parameters (sect131r2, [??]). Figure 2 shows an example of a different curve speed for [mathematical expression not reproducible] on the Raspberry Pi 2B with OpenSSL implementation of elliptic curves. The white colour is for curves with four, grey is for curves with two and black is for curves with zero small domain parameters. As evident, the fastest curve is the curve with the smallest domain parameters.
The curves over the prime field shows a significant anomaly in behaviour. Table II shows the results for measured elliptic curves over the prime field on the Raspberry Pi 2B and also on the MSP430 (for a greater range of samples). The curves with a higher degree are generally slower. However, the curves of the same degree with small domain parameters (a, b, x, y) are not generally faster than curves with normal sized domain parameters (same size as curve degree). Conversely, the small domain parameters had no effect or made the curve even slower than the curves with the same sized domain parameters. Some higher degree curves with normal sized domain parameters (secp128r1, [F.sub.128]) are even comparably as fast as lower degree curves with smaller domain parameters (wtls8, [F.sub.112]). Figure 3 shows an example of a different curve speed for [F.sub.160] on the Raspberry Pi 2B with OpenSSL implementation of elliptic curves. The grey is for curves with two and black is for curves with zero small domain parameters. As we can see the slowest curve is the curve with the smallest domain parameters.
Figure 4 shows the same example as in Fig. 3, but on the MSP430 with our implementation of elliptic curves. The grey is for curves with two and black is for curves with zero small domain parameters. As we can see here also the slowest curve is the curve with the smallest domain parameters.
The results show that on the field of characteristic 2 we can reduce up to 5 % to 15 % of the time consumption on smaller degree curves (114-156 b) and up to 15 % of the time consumption on the higher degree curves (164-572 b) only by choosing the right curve with small domain parameters. On the prime field we can reduce the time consumption by 10 % to 50 % only by choosing the right curve with normal not-smaller domain parameters. The measurements reveal the anomalous behaviour of the prime field curves. This means that it cannot be clearly concluded whether the smaller domain parameters will have a positive effect on speed of elliptic curve operations. They result in reduced memory requirements, but not necessarily a reduction in speed.
From our measurements we expect significant results which should help in choosing the right elliptic curve for a real application from the point of view of time and memory requirement. Our results prove that the size of domain parameters has a significant impact on computational complexity and time consumption of algorithms which work with elliptic curves. Further, we show that the time consumption of an elliptic curve algorithm can be significantly reduced only by choosing the right elliptic curve. Table III shows the results of chosen current and relevant works dealing with ECC optimization, new methods and algorithms or new curves. As we can see, the maximum speed reduction is about 50 %, but very often much smaller.
Our solution shows very close results to the more complex optimization methods by simply only choosing the right curve. This fact might be used for easy speed and memory optimization without any further needs of algorithm change.
The Elliptic Curve Cryptography (ECC) is nowadays already a frequently used method for lightweight secured communication solution and it is spread over wide areas. We might see it also as a solution for future LPWAN, MANET, VANET and many others. We showed as an example the Smart Grid network (Fig. 1), in which the low-power devices are used to gather the sensitive customers or network data from sensors as well as crucial management data. For securing this communication, these devices with limited physical resources need a sufficiently secure and resource effective cryptographic solution. For this purpose, the AES cipher and ECC are often used together, the ECC being always more resources demanding.
Many current works focused on improving the efficiency of ECC are dealing with developing new efficient algorithms, creating new efficient curves or trying to implement or develop new primitives. However, this paper shows an efficient and easy deployable solution for the speed optimization of ECC algorithms without the need of changing current algorithms, primitives or protocols. Our solution is based on choosing the right elliptic curve with right domain parameters. We provide measurements of more than 60 elliptic curves (Section IV) on two different hardware devices (limited and not-limited) with two different software implementations (our software and OpenSSL). These measurements show a significant impact of the domain parameters on the speed of basic elliptic curve operations. Compared with other works (focused on new algorithms, curves or more efficient operations), we achieved comparable results by only choosing the right elliptic curve and with a deeper look at its domain parameters (up to 50 % time reduction). Further, section V shows that many other current works achieved same or smaller time reduction by using much more complex methods. Last but not least, these facts demonstrate that in-depth research of elliptic curve parameterization might bring valuable results.
Future work should investigate the relationship between the domain parameters and the common computational algorithms in greater detail (i.e. point multiplication algorithms). Mathematical analysis is required for a deeper understanding of the speed dependency. We believe this research will bring very significant and valuable information for future cryptosystems and new elliptic curves.
Manuscript received 29 April, 2017; accepted 21 July, 2017.
Research described in this article was financed by the National Sustainability Program under grant LO1401. For the research, the infrastructure of the SIX Center was used.
TABLE A-I. LENGTH OF DOMAIN PARAMETERS FOR MEASURED ELLIPTIC CURVES OVER FIELD OF CHARACTERISTIC 2. Curve m a b x y n name [b] [b] [b] [b] [b] [b] GF([2.sup.114]) wtlsl 114 1 1 113 112 112 wtls4 114 110 112 112 112 113 sect113r1 114 110 112 112 112 113 sect113r2 114 111 112 113 112 113 sect113k1 114 110 112 112 112 113 GF([2.sup.132]) and GF([2.sup.156]) sect131r1 132 131 130 128 131 131 sect131r2 132 130 131 130 131 131 ipsec3 156 0 19 7 9 154 GF([2.sup.164]) and GF([2.sup.186]) wtls3 164 1 1 162 162 163 wtls5 164 163 160 163 161 163 sect163r1 164 163 163 162 159 162 sect163k1 164 1 1 162 162 163 c2pnb163v1 164 163 160 163 161 163 c2pnb163v2 164 161 163 158 163 162 c2pnb163v3 164 163 162 162 163 162 c2pnb176v1 177 176 175 176 175 161 ipsec4 186 0 13 5 4 184 GF([2.sup.234]) and GF([2.sup.240]) wtls10 234 0 1 233 233 232 wtlsll 234 1 231 232 233 233 sect233r1 234 1 231 232 233 233 sect233k1 234 0 1 233 233 232 sect239k1 240 0 1 238 239 238 c2tnb239v1 240 238 239 239 239 238 c2tnb239v2 240 239 239 238 239 237 c2tnb239v3 240 233 239 239 238 236 GF(2284) sect283r1 284 0 1 283 281 281 sect283k1 284 281 282 283 282 282 GF(2410) sect409r1 410 0 1 407 409 407 sect409k1 410 1 406 409 407 409 GF(2572) sect571r1 572 0 1 570 570 570 sect571k1 572 1 570 570 570 570 TABLE A-II. LENGTH OF DOMAIN PARAMETERS FOR MEASURED ELLIPTIC CURVES OVER PRIME FIELD. Curve p a b x y n name [b] [b] [b] [b] [b] [b] GF(112) and GF(128) wtls6 112 112 111 108 112 112 wtls8 112 0 2 1 2 113 secp112r1 112 112 111 108 112 112 secp112r2 112 111 111 111 112 110 secp128r1 128 128 128 125 128 128 secp128r2 128 128 127 127 126 126 GF(160) wtls7 160 160 160 159 160 161 wtls9 160 0 2 1 2 161 secp160r1 160 160 157 159 158 161 secp160r2 160 160 160 159 160 161 secp160k1 160 0 3 158 160 161 GF(192) secp192k1 192 0 2 192 192 192 prime192v1 192 192 191 189 187 192 prime192v2 192 192 192 192 191 192 prime192v3 192 192 190 191 190 192 GF(224) wtls12 224 224 224 224 224 224 secp224r1 224 224 224 224 224 224 secp224k1 224 0 3 224 223 225 GF(256) secp256k1 256 0 3 255 255 256 prime256v1 256 256 255 255 255 256
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Radek Fujdiak (1), Petr Dzurenda (1), Petr Mlynek (1), Jiri Misurec (1), Milos Orgon (2), Bezzateev Sergey (3)
(1) Department of Telecommunications, Brno University of Technology, Technicka St. 12, 616 00 Brno, Czech Republic
(2) Department of Telecommunications, Slovak University of Technology in Bratislava, Ilkovicova St. 3, 812 19 Bratislava, Slovak Republic
(3) Technologies of Information Security, Saint-Petersburg University of Aerospace Instrumentation, Bolshaya Morskaya St. 67, 190 000 Saint Petersburg, Russia email@example.com
Please Note: Illustration(s) are not available due to copyright restrictions.
Caption: Fig. 1. Smart Grid network for remote data acquisition .
Caption: Fig. 2. Comparison of different curves over field of characteristic [mathematical expression not reproducible] on Raspberry with OpenSSL implementation.
Caption: Fig. 3. Comparison of different curves over prime field F160 on Raspberry with OpenSSL implementation.
Caption: Fig. 4. Comparison of different curves over prime field [F.sub.160] on MSP430 with our implementation of elliptic curves.
TABLE I. EXPERIMENTAL RESULTS FOR MEASURED ELLIPTIC CURVES OVER FIELD OF CHARACTERISTIC 2 ON RASPBERRY. Curve Field No. tG1 At1 name [-] [[micro]M] [%] GF(2114) wtlsl [2.sup.114] 2 3,362 0.00 wtls4 [2.sup.114] 0 3,496 +3.99 sect113r1 [2.sup.114] 0 3,500 +4.10 sect113r2 [2.sup.114] 0 3,528 +4.94 sect113k1 [2.sup.114] 0 3,487 +3.72 GF([2.sup.132]) and GF([2.sup.156]) sect131r1 [2.sup.132] 0 6,235 0.00 sect131r2 [2.sup.132] 0 6,464 +3.67 ipsec3 [2.sup.156] 4 6,417 +2.92 GF([2.sup.164]), ([2.sup.177]) and GF([2.sup.186]) wtls3 [2.sup.164] 2 8,174 +2.14 wtls5 [2.sup.164] 0 8,815 +10.15 sect163r1 [2.sup.164] 0 8,802 +9.98 sect163k1 [2.sup.164] 2 8,197 +2.42 c2pnb163v1 [2.sup.164] 0 8,822 +10.23 c2pnb163v2 [2.sup.164] 0 8,795 +9.92 c2pnb163v3 [2.sup.164] 0 8,795 +9.90 c2pnb176v1 [2.sup.177] 0 8,739 +9.20 ipsec4 [2.sup.186] 4 8,003 0.00 GF([2.sup.234]) and GF([2.sup.240]) wtls10 [2.sup.234] 2 15,865 +0.23 wtlsll [2.sup.234] 1 17,474 +10.40 sect233r1 [2.sup.234] 1 17,493 +10.52 sect233k1 [2.sup.234] 2 15,828 0.00 sect239k1 [2.sup.240] 2 16,244 +2.63 c2tnb239v1 [2.sup.240] 0 17,890 +13.03 c2tnb239v2 [2.sup.240] 0 17,843 +12.73 c2tnb239v3 [2.sup.240] 0 17,784 +12.36 GF(2284) sect283r1 [2.sup.284] 1 32,072 +11.91 sect283k1 [2.sup.284] 2 28,659 0.00 GF(2410) sect409r1 [2.sup.410] 2 76,160 +14.35 sect409k1 [2.sup.410] 1 66,605 0.00 GF(2572) sect571r1 [2.sup.572] 2 174,749 +14.86 sect571k1 [2.sup.572] 1 152,143 0.00 TABLE II. EXPERIMENTAL RESULTS FOR MEASURED ELLIPTIC CURVES OVER PRIME FIELD ON RASPBERRY PI 2B AND MSP430. Curve Field n [t. [DELTA] [t. [DELTA] sub.G1] [t.sub.1] sub.G2] [t.sub.2] name [-] [[mu]s] [%] [[mu]s] [%] GF(112) and GF(128) wtls6 112 0 2,555 0.00 10,696 +8.68 wtls8 112 4 2,953 +15.58 10,897 +10.72 secp112r1 112 0 2,570 +0.59 9,842 0.00 secp112r2 112 0 2,599 +1.72 11,413 +15,96 secp128r1 128 0 2,825 +10.57 12,092 +22,86 secp128r2 128 0 2,899 +13.46 12,986 +31,94 GF(160) wtls7 160 0 4,130 0.00 13,031 0.00 wtls9 160 4 4,704 +13.90 19,612 +50.50 secp160r1 160 0 4,143 +0.31 13,050 +0.15 secp160r2 160 0 4,143 +0.31 13,963 +7.15 secp160k1 160 2 4,557 +10.34 15,080 +15.72 GF(192) secp192k1 192 2 6,364 +11.92 23,674 7.57 prime192v1 192 0 5,716 +0.53 25,400 13.04 prime192v2 192 0 5,686 0.00 22,470 0.00 prime192v3 192 0 5,701 +0.26 24,171 5.36 GF(224) wtls12 224 0 7,483 +0.09 26,631 0.00 secp224r1 224 0 7,476 0.00 27,020 1.46 secp224k1 224 2 8,388 +12.20 30,771 15.55 GF(256) secp256k1 256 2 11,007 +12.28 -- -- prime256v1 256 0 9,803 0.00 -- -- TABLE III. COMPARISON OF SPEED REDUCTION WITH OTHER CURRENT AND RELEVANT WORKS. Speed Short description reduction #Ref. [%] Work focused on the use of ECC in wireless 46-48 % sensor networks. They present a new technique (D&A) to speed up the multiplication operation. 32-37 % L26J (wNAF) Work focused on double-and-add algorithm for point multiplication and application to the no data  Fibonacci sequence. The work compares only chain size, where they achieved up to 18 % differences. But final speed tests are missing. Another work focused on new more efficient design of elliptic curve point multiplication 4-38 %  based on Montgomery modular multiplication. The authors introduce the new curve 25519 with significant speed efficiency on hardware. A final no data  comparison of this curve on specific hardware and with other curves is missing. The work focused on ECC in the Internet of Things. The authors implement their solution of ECDSA on a small processor and gain 50 %  significant speed results compared to the other implementations by using FPGA acceleration. Another work providing a new algorithm based on modified traditional extended Euclidean >50 %  Great Common Divisor (GCD).
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|Author:||Fujdiak, Radek; Dzurenda, Petr; Mlynek, Petr; Misurec, Jiri; Orgon, Milos; Sergey, Bezzateev|
|Publication:||Elektronika ir Elektrotechnika|
|Date:||May 1, 2017|
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