Dimov Stojce Ilcev / International Journal of New Technologies in Science and Engineering Vol. 2, Issue. 4,October 2015, ISSN 2349-0780

ENCRYPTION OF VOICE, DATA AND VIDEO (VDV) FOR SECURE TERRESTRIAL AND SATELLITE COMMUNICATIONS

Stojce Dimov Ilcev Durban University of Technology (DUT), 133 Bencorrum, 183 Prince Street, Durban, South Africa

Abstract: This paper introduces the Voice, Data and Video (VDV) as protection shield for secure terrestrial and satellite communication systems deploying special hardware and software scrambling solutions against government or private surveillance and spying. The encryption covers fixed, personal and mobile (cellular) solutions including computer, fax and telex messaging modes for commercial and military applications.

Keywords: Encryption, VDV/NSA, DES/AES, RSA/IBE

I. INTRODUCTION

Secure communication is when two entities are communicating and do not want a third party to listen in or to communicate in a way not susceptible to eavesdropping or interception. It includes means by which people can share mutual information with varying degrees of certainty that third parties cannot intercept what was said, heard, sent and saw. Other than spoken face-to-face communication with no possible eavesdropper, it is probably safe to say that no communication is guaranteed secure in this sense, although practical obstacles such as legislation, resources, technical issues (interception and encryption), and the sheer volume of communication serve to limit surveillance. In , encryption is the process of encoding voice (speech and fax), data (messages or text) and video (TV, videoconference and images) in such a way that only authorized parties can listen, read or see it properly. Encryption does not of itself prevent interception, but denies the speech, message and image content to the interceptor. In an encryption scheme, the speech, message or image information, referred to as secure , is encrypted using an encryption algorithm, generating that can only be read if decrypted. For technical reasons, an encryption scheme usually uses a pseudo-random encryption generated by an algorithm. An authorized recipient can easily decrypt the message or voice with the key, provided by the originator to recipients but not to unauthorized interceptors. However, it is in principle possible to decrypt the message without possessing the key, which requires very large computational resources and skill are required.

II. ENCRIPTION STANDARDS

Ongoing news reports in the international media have revealed operational details about the US (NSA) and its international partners’ global surveillance of foreign nationals and US citizens. The reports mostly emanate from a cache of top-secret documents leaked by ex-NSA contractor Edward Snowden, who obtained them while working for B.A. Hamilton, one of the largest contractors for defense and intelligence in the US government.

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To prevent surveillance and cracking data, today are used a number of standards and protocols related to cryptography. There are many cryptographic algorithms available in the market to encrypt the computer or other devices data, which strengths depend upon the cryptographic system. Crypto systems are composed from cryptographic primitives such as encryption algorithm, number of keys, hash and round functions, memory elements, real time operating system, etc. Some important encryption algorithms are: - Data Encryption Standard (DES) was once a predominant symmetric-key algorithm for the encryption of electronic data. It was highly influential in the advancement of modern cryptography in the academic world. Developed in the early 1970s at IBM and endorsed by the US National Institute of Standards and Technology (NIST). It uses a 56-bit key to encrypt the 64 bit block size data. It processes 64-bit inputs into 64-bit cipher-text and algorithm performs 16 iterations. However, DES was susceptible to brute-force attacks, and as a result it was phased out at the start of the 21st century by a more secure encryption standard AES. - Advanced Encryption Standard (AES) is the first publicly accessible, from the NSA for the classification “top secret” approved cipher. It started in 1997 as one of the most frequently used and most secure encryption algorithms available today. Thus, this algorithm is based on several substitutions, permutations and linear transformations, each executed on data blocks of 16 byte, therefore the term . Those operations are repeated several times, called “rounds”. During each round, a unique round key is calculated out of the encryption key, and incorporated in the calculations. The AES encryption system offers AES-128, AES-192 and AES-256 with drastic improvements compared to the 56-bit key of DES. The 128-bit AES key is not so secure like unbreakable AES-256, however to provide its cracking with a state-of-the-art supercomputer would take longer than the presumed age of the universe. As of today, no practicable attack against AES-256 exists, because 256-bit is secure against any likely future technology, and forthcoming 512-bit is probably secure against even never-imagined hypothetical alien technology. In Table 1 is provided time to crack versus key.

Table 1. Cracking Time of Key Size

- Rivest, Shamir and Adelman (RSA) is a public-key encryption technology developed by RSA Data Security, which is based on the fact that there is no efficient way to factor very large numbers. Deducing an RSA key, requires an extraordinary amount of computer processing power and time. The RSA algorithm is widely used for securing sensitive data, particularly when being sent over an insecure network such as the Internet, built into many software products, including Windows, Microsoft Internet Explorer, Google and other solutions. The technology is so powerful that the US government has restricted exporting it to foreign countries. The RSA key length of 1024-bits is sufficient for many medium-security purposes such as web site logins and long-term confidential data. The 2048-bit is for a contingency plan for migrating to larger key sizes and to keep data confidential for more than the next two decades. The new coming 3072-bit promises more reliable a key size larger than 2048-bits. - Elliptical Curve Cryptography (ECC) is a public key encryption technique based on elliptic curve theory that can be used to create faster, smaller and more efficient cryptographic keys. It was discovered in 1985 by Victor Miller (IBM) and Neil Koblitz (Washington University) as an alternative mechanism for implementing public-key cryptography.

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Public-key algorithms provide sharing keys among large numbers of participants or entities in a complex information system. Unlike other popular algorithms such as RSA, ECC is based on discrete logarithms that are much more difficult to challenge at equivalent key lengths. These benefits of ECC were very important to the NSA as it chooses its security for use over several decades in its crypto hardware [1, 2, 3].

III. IMPORTANCE AND EFFECIENCY OF ENCRIPTION SECURITY

Therefore, encryption plays an important role in mitigating risk related to the many threats and cracklings. If sensitive information stored on computers is well encrypted, it will take a secret key to decode it. If sensitive information en route to others is encrypted, only someone that knows the secret key can read what it says. When sensitive information is encrypted and it ends up logged by others in the course of communicating online, encryption keeps those without the secret key from knowing the contents of the message. In addition to the theoretical comparisons and experimental analysis between DES and AES algorithms in Table 2 is shown a comparative study between DES and AES into nine factors, such as key length, cipher type, block size, developed, resistance, security, possibility key, possible ACSII printable character keys and time required to check all possible key. Based on the text files used and the experimental result it was realized that AES algorithm consumes least encryption and decryption time as compared to DES algorithm. Otherwise, new proposed Hybrid Encryption Algorithm using Block cipher and symmetric key provides a more secure and convenient technique for secure data trans-mission for all kind of applications

Table 2. Comparison between DES and AES for VDV Encryption

According to the NIST, keys for symmetric ciphers such as AES must be matched in strength by public key algorithms such as RSA and ECC. For example, a 128-bit AES demand a 3072-bit RSA key, while 256-bit AES demands an RSA key size of 15,360-bits for equivalent security. Clearly, 15,360-bits would bring almost any system to its knees since key size is directly related to computing resources. Thus, a message encrypted using a modern One-time Pad cannot be broken because the encryption key is a random number and because the key is used only once. Before today no one thought it was possible to successfully break a 923-bit . And even if it was possible, scientists estimated it would take thousands of years. Table 3. Cost Comparison between PKI and IBE Encryption Solutions

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One of the biggest questions right now is how powerful the government’s code-breaking tools are, and the extent to which they are capable of cracking the algorithms, and at what speed, that power modern encryption programs. However, the US government doesn’t tell in public how many codes it can break, but even if the government can’t crack the codes just yet, there is still the anonymity problem of the government seeing who sent what to whom. As stated before, encryption is a way of covering important information with a code before it is sent over the Internet or other transmission systems to the end users. That means other machines and people cannot read it illegally. Therefore, encryption of any kind of transmissions is very important for everyone and according to the importance of information all users need different level of encryption. For instance, every user of PC or cellular phone needs to protect own password and data inside memory device, while some government or corporations officials and institutional need very sophisticated and unbreakable encryption systems to cover all memory storage units and end-to-end VDV communications. The topic can be intimidating for those without extensive computer experience, but thankfully, for most users, keeping sensitive data unbreakable and safe is a relatively straightforward process. The key is to start early and regularly verify the effectiveness of the chosen security measures and how is the cost to deploy reliable encryption system? For instance the price of full disk encryption is about 232 $ per user, while the true cost of E-mail encryption is up to a significant difference between a traditional Identity-Based Encryption (IBE) solution and Trend Micro Encryption .are different. All of these costs add up to a significant difference between a traditional Identity-Based Encryption (IBE) vs Public Key Infrastructure (PKI) solution of Trend Micro Encryption. Thus, based upon Enterprise Strategy Group’s (ESG) estimates, the Trend Micro solution (PKI) costs shown in Table 3 are about 78% less than the PKI equivalent [2, 3, 4, 5].

IV. CELLULAR (MOBILE) ENCRYPTION SYSTEM

Cellcrypt a provider of encrypted voice calling solutions for mobile phones is offering mobile encryption for voice calls on leading smartphones, such as Android, BlackBerry, iPhone and Nokia, for government-grade security in an easy-to-use application that makes secure calling as simple as making a normal call on the same device. This software solution allows many types of cell phones to be supported and can be deployed to users in remote locations over the air in minutes. However, all smartphones, as computers, are preferred targets of attacks.

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Figure 1. Mobile encrypted Phones – Courtesy of Manual: by GSMK [3]

These attacks exploit weaknesses related to smartphones, like SMS, MMS, WiFi networks, Bluetooth and GSM, which are de facto global standard for mobile communications. There are also attacks that exploit software vulnerabilities from both the Web browser and operating system. Finally, there are forms of malicious software that rely on the weak knowledge of average users. Different security counter-measures are being applied to smartphones, from security in different layers of software to the dissemination of information to end-users. To make safer your calls it will be necessary for all mobile users to deploy some kind of the following mobile encryption devices: - CryptoPhone 500 of German GSMK producer is an Android-based secure mobile phone with true 360° mobile device security for secure messaging and Voice over IP (VoIP) communication on any network, shown in Figure 1 (Left). It is providing renowned end-to-end voice and message encryption with a highly sophisticated approach towards mobile device protection for secure end-to-end encrypted VoIP calls on any network, such as GSM, 3G UMTS/W-CDMA, 4G WiMAX and Wireless LAN (WLAN). - Another GSMK CryptoPhone 400 is a touch screen-based phone for secure VoIP on any GSM, 3G/4G or WLAN networks, shown in Figure 1 (Middle). This IP crypto phone is unmatched flexibility combined with secure messaging, a hardened operating system and encrypted storage for mutual confidential contacts, messages and notes. - Rohde&Schwarz (R&S) TopSec Mobile is a mobile encryption device for secure worldwide VoIP-based communications on smartphones and laptops, which is illustrated in Figure 1 (Right). These units are a highly versatile voice encryption device in terms of its ability to connect to communications terminal equipment and networks by many companies and government authorities to share confidential information. In such a way, with its Bluetooth interface, it provides a dependable wireless connection to communications terminal equipment such as smartphones, laptops or satellite communication terminals (Inmarsat/Thuraya). Users can make confidential and encrypted calls either directly with the TopSec Mobile or with a headset. As an alternative, this unit can be connected to a laptop via a USB cable to set up an encrypted IP connection where a wireless connection is undesirable. Cellcrypt Mobile Baseline provides end-to-end voice call encryption on commercially available off-the-shelf BlackBerry smartphones. It is an easy-to-use software solution that makes secure calling as easy as making a normal mobile phone call and uses the IP data channel of mobile (2G, 3G, and 4G) networks, which network is shown in Figure 2 [3, 4, 5, 6].

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V. VOICE (FAX) AND DATA ENCRYPTION

The new voice encryption of the US Government is Secure Terminal Equipment (STE) currently in use since 2008 as encrypted telephone communications system for wired or “landline” telephone communications via Integrated Services for Digital Network (ISDN) telephone lines up to 128 KB/s.

Figure 3. Voice (Fax) and Data Encryption Devices – Courtesy of Manual: by R&S [6]

The greater bandwidth allows higher quality voice, fax and data transmission through a built-in RS-232 port, which is a standard for serial communication transmission of data. The STU-II is a secure telephone developed by the US NSA, which permits up to six users to have secure communications, on a time-shared basis. Samples about two Rohde&Schwarz (R&S) voice (fax) and data encryption devices are presented: - The R&S MKS9680 is a highly secure multifunctional device for encrypting voice, facsimile (fax) and data transmission over analog and digital landline networks, including satellite fixed and mobile links, shown in Figure 3 (Left). It meets even the most demanding requirements in terms of cryptographic and emanation security, including resistance to mechanical attacks, capable of operating in poor-quality networks. This is a is a modular device, available in different configurations and designed to support various use scenarios. And is equipped with interfaces for operation in heterogeneous networks. - The R&S ELCRODAT 5-4 (ED5-4) is used by military and government authorities for the encrypted transmission of voice (no fax) and data signals in analog and ISDN networks, shown in Figure 3 (Right). It provides secure end-to-end encryption, which protects messages against ckracking and manipulation attacks along the entire transmission path. It uses a tried-and-tested special NATO algorithm for encryption and has an expansion slot for cryptological capabilities of the device for new or additional requirements.

VI. MULTIPURPOSE ENCRYPTION SYSTEMS

The multipurpose product family provides end-to-end voice and fax encryption at the highest security level, across networks. The following two family products for encrypted transmission are the ideal solution when confidential and tap-proof information is to be transmitted:

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Figure 4. Multipurpose Encryption Devices – Courtesy of Manual: by R&S [6]

Figure 5. Video Encryption Devices – Courtesy of Manual: by Decom [8]

- R&S TopSec encryption devices offer a suitable security solution for every application, such as communications as well as video, data and fax transmissions, shown in Figure 4 (A-Left). Deploying this device, mobile phone users can choose between the TopSec GSM, a mobile phone enhanced with a crypto module, shown in Figure 4 (A-Middle), and the TopSec Mobile, a voice encryption device equipped with a Bluetooth interface, shown in Figure (4-Right). However, users with a digital Euro ISDN connection employ the TopSec 703+, those with an analog connection use the TopSec 711, which are intertoperable with the TopSec Mobile, TopSec GSM encryption devices. - R&S ELCRODAT 6-2 is the high-end encryption system, which provides secure voice, fax, data and video conferencing transmissions of classified information up to top cecret, shown in Figure 4 (B). It can be used for ISDN/PBX, Inmarsat and other satellite links, permiting up to 30 simultaneous single-channel encryption. A typical application of this version is the 2 MB/s port encryption at the frontend of ISDN PBX systems [1, 6, 7, 8].

VII. VIDEO ENCRYPTION SYSTEMS

Image and Video Encryption provides a unified overview of techniques for encryption of images and digital video data including TV encryption, such as follows: - Polycom VVX 1500D Video Conferencing System is an affordable, easy-to-use, dual stack business media phone for H.323 and Session Initiation Protocol (SIP) environments, shown in Figure 5 (Left). This unit combines one-touch video calling, integrated business applications and advanced IP telephony in flexible and future-proof Unified Communications (UC) solutions. It enables managers and knowledge workers to make simple and fast touch screen video and voice calls right from their workspace and one-touch business-grade video conferencing right from the desktop. The adjustable camera, base, and display provide eye-level visual interactions. The voice telephony requires integration with an IP PBX platform from a Polycom Voice Interoperability Partner (VIP). This unit uses security AES 128-bit

Available online @ www.ijntse.com 323 Dimov Stojce Ilcev / International Journal of New Technologies in Science and Engineering Vol. 2, Issue. 4,October 2015, ISSN 2349-0780 encryption standard for multimedia streams, H.235v3 Media encryption via SRTP Transport Layer Security (TLS), Encrypted configuration files, Digest , Password login, Support for URL syntax with password for boot server address, HTTPS secure provisioning and Support for signed software executables. - StarLeaf PT Mini is a video communication device connected to any screen or monitor and makes user desk to a full conference environment via certificate-based encryption, shown in Figure 5 (Right). The plug-and-play functionality allows its installation in a few seconds transforming users desktop into a high-definition telepresence solution for video and audio calls. It is a powerful personal video calling and conferencing device designed to work with any screen or monitor for fixed, portable and mobile environments.

Figure 6. Network Encryption Devices – Courtesy of Manual: by R&S [6]

VIII. NETWORK ENCRYPTION SYSTEMS

Network encryption provides private and secure systems for organizations, which guards against spying on regular data and provides valuable protection for all other classes of data transfer. Although network-level encryption is a relatively mature technology, organizations need to make several choices when deciding what kind of network encryption to deploy: - R&S SITGate Next-Generation Firewall is a multifunctional encrypted network system that uses the latest technology for analyzing data traffic at very high speed for secure access to Internet and cloud services, shown in Figure 6 (Left): L-Series (Bellow), M-Series (Middle) and S-Series (Top). The firewall blocks hazardous or unauthorized use and warns of attacks and abuse, providing the secure site-to-site networking with IP and Virtual Private Network (VPN) encryption standards. Thus, VPN enable users to access private networks over the Internet from remote sites, home offices and mobile devices. When it comes to network security, dedicated encryption devices afford greater protection than network equipment with built-in encryption capabilities. Prior to encryption and authentication, network traffic can be prioritized according to network ports and applications. Telephony, for instance, can be given higher priority than, say, E-mail traffic. - R&S KGE3000 Key Generation Equipment True random data for security management applications, shown in Figure 6 (Right). This hardware-based true random number generator delivers output optimized to the specific requirements of security management applications. Namely, two separate and independent physical sources provide the raw data for the random numbers. The mathematical post processing uses AES-256 with CBC-MAC with a fixed key and initialization vector to produce the 16 random bytes. Therefore, AES-256 is ideal for a massively parallel brute-force attack and the use of the CBC-MAC doesn’t hurt the system.

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IX. INTEGRATED ENCRYPTION SYSTEMS

An effective voice and data encryption technologies must ensure that unauthorized users cannot circumvent controls by accessing the data at a level above the encryption mechanism. This system requires linking the strong access control, host, application integrity protection and significant data encryption into the following integrated comprehensive R&S systems: - R&S SITLine ETH Ethernet Encryptor is the modern concept of next-generation firewalls for secure data transmission via landline, radio relay and satellite links up to 40 GB/s, shown in Figure 7 (Left). This unit maximizes network security by employing a completely application-based approach to positively validate all network traffic and permanently analyzes every single IP packet in order to determine its application type and content. Only data that is fully validated can pass.

Figure 7. Integration Encryption Devices – Courtesy of Manual: by R&S [6]

- R&S ELCRODAT 4-2 is a fully ruggedized HF/VHF/UHF and satellite communications security for voice and data tactical crypto device used to encrypt and decrypt voice and data communications, shown in Figure 7 (Right). It is perfectly suited for deployment on stationary and mobile platforms in rugged terrain and in naval and airborne environments. A customizable crypto algorithm provides the uniqueness and exclusivity needed for different national and coalition scenarios. The data crypto mode is seamlessly integrated into data transmission systems and vocoder is used in voice mode optimizes speech clarity even in noisy transmissions.

X. SATELLITE ENCRYPTION SYSTEMS

Some of CryptoPhone IP secure mobile and desktop phone devices can be connected to Inmarsat BGAN, Thuraya IP and other satellite terminals either via a simple Ethernet cable or an encrypted Wireless LAN connection, thus guaranteeing end-to-end encrypted communications on any network, any time. However, during the last few decades have been developed new powerfull fixed, transportable and mobile stallite systems known as Digital Video Broadcasting- Return Channel via Satellite (DVB-RCS), which also are deploying encryption systems for customers wordwide. Here will be presented DVB-RCS transceiver and adequate encryption telephone: - Evolution X3 iDirect Series Satellite Router is a next-generation satellite router that implements DVB-S2 Adaptive Coding and Modulation (ACM) standard, shown in Figure 8 (A) together with antenna system, The X3 is ideally suited satellite transceiver for broadband connectivity such as Internet and VPN access to the government and enterprise networks, as well as real-time VoIP, data and video conferencing

Available online @ www.ijntse.com 325 Dimov Stojce Ilcev / International Journal of New Technologies in Science and Engineering Vol. 2, Issue. 4,October 2015, ISSN 2349-0780 or Voice, Data and Video over IO (VDVoIP) applications. This device can be optionally deployed with can be AES 256-bit or higher standard encryption system.

Figure 8. Satellite Encryption Devices – Courtesy of Manuals: by iDirect/GSMK [9, 2]

Figure 9. Rack and Plug-in Card R&S CryptoServer – Courtesy of Brochure: by R&S [6]

The similar device known as Evolution X5 Series Satellite Router is designed specifically to support business-critical applications for broadband applications such as enterprise connectivity, cellular backhaul, maritime, secure banking, and other mobile applications. - GSMK CryptoPhone IP 19 is a secure IP desktop phone for end-to-end either fixed, mobile and satellite (Inmarsat/Thuraya) encrypted VoIP communications via any IP network, shown in Figure 8 (B). This phone features a Gigabit Ethernet interface with an R45 plug and supports wireless LAN. It uses the same encryption engine as GSMK’s secure mobile and satellite phones, featuring 256-bit AES and other type of encryption.

XI. CRYPTO SERVERS

The R&S Crypto server equipment is a highest level of security for confidential data and cryptographic keys, which is used as a Hardware Security Module (HSM) for the protection of data and transactions. It is available as a complete server in rack format (LAN HSM), shown in Figure 9 (Left) and as a plug-in card (PCI/PCIe HSM), shown in Figure 9 (Right). The CryptoServer meets highest international security standards and is certified by the German Federal Office for Information Security (BSI) and the US NIST. Via Application Program Interface (API), this unit is integrated into existing IT systems such as Public Key Infrastructures (PKI) for ID and inspection systems, where it is used to encrypt and sign confidential data [2, 6, 7, 8].

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XII. CONCLUSION

The encryption and decryption of any voice, facsimile, data or video network is providing enough a secure key from different encryption systems, which is used for many types of transmissions encryption. For this purpose asymmetric key is used along with the linear block cipher algorithm. However, the block cipher algorithm is more efficiently using in symmetric encryption technique. Thus, AES algorithm along with the use of RSA algorithm for key management will provide an efficient technique to ensure the security of transmitted data. The security RSA AES is better than RSA-DES and the proposed the proposed Hybrid Encryption Algorithm is showing more efficiencies than RSA AES during the application of data transmission. Therefore, in this paper a new comparative study between DES and AES algorithms were presented, which include the theoretical comparisons, experimental analysis and comparison is done for DES and AES algorithms. Based on the text files used and the experimental result it was concluded that AES algorithm consumes least encryption and decryption time as compared to DES algorithm. REFERENCES

[1] R. Smith, “Understanding Encryption and Cryptography Basics”, 2015 at: [http://searchsecurity.techtarget.com/Understanding-encryption-and-cryptography-basics]. [2] IJET, “Comparison of Various Encryption Algorithms”, 2012 at: [http://iet-journals.org/archive/2012/jan_vol_2_no_1/794713132491542.pdf]. [3] GSMK CryptoPhone, “Cryptophone Devices”, Germany, 2015 at: [http://www.cryptophone.de/en/products/]. [4] S. Soni & Others, “Analysis and Comparison between AES and DES Cryptographic Algorithm”, IJEIT, 2012. [5] Oltsik J., “The True Costs of E-mail Encryption”, Enterprise Strategy Group, 2010. [6] Rohde&Schwarz, “R&S Products Overview – Secure Communications, 2015 at: [www.rohde-schwarz.de]. [7] Global TSCM Group, “Voice, Data and Fax Encryption”, Stealth, Syosset, NY, 2015 at: [http://thestealthmall.com/cart/voice-data-fax-encryption-p805/] [8] Decom, “Video Conferencyng”, 2015 at: [www.dekom.com]. [9] iDirect, “Satellite Routers”, 2015 at: [www.idirect.net

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