Illegal use of VOIP - Essay Example

Illegal use of VOIP Voice over Internet Protocol or VoIP enables a person to make telephone calls using broadband internet instead of the usual telephone line. The most important advantage of this technique over the regular telephone service is that the charge that has to be paid is much less in VoIP. Because of this fact more and more people are using this method especially to make long distance international calls. The number of VoIP service providers is increasing day by day. Nowadays there are many such providers which include consumer IP telephony services, which are provided by legacy telephone carriers, IP-PBX services provided by enterprises (Private Branch eXchange). There is also IP telephony outsourcing services also known as IP Centrex services which is provided for enterprises by ISPs (Internet service providers or carriers). IP telephony services require interoperation of IP networks and this open nature of the IP networks open niche for its illegal uses. Nowadays these services are provided by unlicensed VoIP providers. The present paper is intended to analyze the factors leading to such illegal use of VoIP, the methods of illegal use and how this problem could be circumvented. The principle behind VoIP is that using a computer and a microphone it is possible to record sound of a person. In this process, the sound would be sampled at a very high rate and then would be stored as files in the computer. Each of these samples is a small bit of sound by the respective person. Now the computer would be able to use these samples in such a way that a listener would be able to hear accurately what the speaker has said. In VoIP, the difference is that the recorded samples are send through IP services to another computer placed at a distant place. So the speaker's voice could be heard as such by a listener sitting at a long distance. For this purpose the computer has to compress the sound samples so that it could be hold in a limited bandwidth with limited frequency. This is done by using compressor/de-compressor or CODEC. Speech CODECs are modified in such a way that the speaker's sound could be reproduced by much accuracy and clarity. The small sound samples are then packed as IP packets for transmission. This process is called packetization. So IP packets would be containing a lot of samples each with a bit of sound and together they form the entire message. If these packets are delivered in the correct time satisfactory results could be obtained. But if it is delayed, it has to be discarded. The process of compression, transmission, the processes by which it is uncompressed and delivered have to take place in a very less time. If the process is delayed or is not occurring according to time there would be echo or over talk (VOIP disadvantages, 2009). VoIP system could be installed in a variety of hardware systems such as a telephone. There is no need of a computer in that case. Some of the VoIP providers allow a customer to contact only a person using the same service. But there are providers who would allow contacting any person with a telephone number and this include land line or mobile or international or long distance numbers. Instead of a computer one could use a VoIP telephone for the purpose. The traditional telephone available with the customer could be used for the purpose with a VoIP adapter. In this case the digital signals of sound would be converted into regular telephone signals before it reaches destination. Above all these in areas where wireless internet connections are possible like in airports, cafes etc, VoIP service could be availed wirelessly (Voice-Over-Internet Protocol, 2009). This makes illegal calls very easy to be made. There is no need of spending money on expensive devices for VoIP services. Without much expenditure, using the existing phone one could easily make long distance calls through VoIP and for the same reason it is difficult for the government to interfere to reduce such illegal practices (How does VoIP works, 2009). According to Burns (2007) in China the illegal use of VOIP for long distance calls is the result of the great increase in the telephone charges. Although it is illegal, most of the service providers offer this facility also through internet connections and as a result nowadays people in China are paying for this unlicensed practice. It is assumed that there would be a tenfold increase in the number of people using this service in the next three to four years. Such services are provided by 'virtual VOIP carriers' or VVC's. They have their own gateways to connect internet to phone networks. Through this they provide PC to phone services. Government is not in a position to detect these unlicensed providers on a time bound basis. Only traditional service providers are allowed to provide IP telephony service as per government regulations. But the price of international calls through either internet phone cards or the usual telephone calls is exorbitantly high. Compared to these, VVC offer the same service at a very lower price. This is the motivation for the people to go for it and even to pay for such an unlicensed service. Telephone operators round the world have lost a significant amount of their profit as a result of interconnection bypass. This is mainly because of increased use of GSM VoIP gateways (Battling illegal call operations with fraud management systems, 2009). These gateways are also called SIM boxes. Because of the development in the technologies of this system these gateways could easily route calls from mobile or landline to relevant GSM network through VoIP. It is now possible to use hundreds of mobile SIM cards, do remote pre-paid recharging, provide SIM rotation facility and it is also possible to feature antenna splitters. It is also possible to store many SIM cards off site. Installing GSM gateways in offices to save costs on office to mobile calls is legal in many countries. But using these gateways for commercial telecommunication services without a GSM operator's approval is illegal. Nowadays GSM operators are increasingly using Fraud management systems to catch these culprits. It is possible to do detailed analysis of Call Detail Records (CDR) to find out the international call termination and also to block SIM cards of mobiles doing such illegal activities. Unusual user behavior patterns could be easily detected using fraud management systems. But the fraud operators are discovering new techniques to avoid detection by fraud management systems. There are several ways of detecting illegal use of VoIP. Most of the illegal users would divert all calls to mailboxes and they would never pick up the calls. This would allow easy detection by fraud management systems. Some more advanced illegal users allow all the voice calls to be accepted in their gateway. Then the calls made by subscriber from the missed call list would be received on the GSM gateway. When the subscriber hears no sound from the other end, there is also chances of calling again and again thus providing GSM gateway with a number of incoming calls. Thus the user patters as such would be normal and would not be easily detected by the Fraud management systems. Therefore now these systems are checking duration of calls also in addition to patterns to detect them. This is because in such cases the duration of incoming calls would be very less. Nowadays the illegal users also give pre-recorded messages such as 'please wait for a minute' etc and thus they overcome detection by checking the duration of calls also. The ratio of on-net calls to off-net calls is another indication of illegal usage. If on-net calls accounts to 90 to 100% of all calls, it could be presumed that illegal users are using it. Still another method of detection is to check the mobility of SIMs. Usually SIMs used for the illegal purpose would be having very less mobility. The illegal users would be using the gateways usually during nights. Unusually large number of calls at night also enables detection of illegal users easy. Most of the mobile SIM cards used for fraud activities are prepaid. It is also possible to concentrate on the most recently activated SIM cards for detection purposes. If the subscriber has given false data regarding the contact address there is an increased chance of using that SIM for illegal purposes. This would also allow detection of such users. A Fraud management system which use multiple detecting technique and that could incorporate more and more techniques to counteract fraudster easily would be best for the purpose. The team should be well aware of the most recent fraud techniques adopted by the illegal users. There should also be test calls to mobiles to detect illegal users. Most of the enterprises install firewalls to filter out unwanted packets from internets to intranets. This would prevent illegal access to internets (Fukuyama et al., 2003). This also prevents illegal use to some extent. The government could make the use of such firewalls mandatory in all the enterprises with PBX facility and this could solve the problem to a great extent. Thus it could be seen that VoIP is been used increasingly world wide as a reault of the reduced charge for long distance calls compared to traditional phones. The open nature of internet facilitates such illegal use with the help of GSM gateways, which is installed in most of the big offices. The techniques available to detect such use are not very efficient since the illegal users always find method to avoid detection. Use of firewalls in offices with PBX facility could be recommended to prevent illegal use to some extent References "Battling illegal call operations with fraud management systems" [online] Available at: http://www.nokiasiemensnetworks.com/NR/rdonlyres/3BEAAC03-80DF-40A4-8154-0E1001FBFAA7/0/Fraud_Management_white_paper.pdf (2009) (accessed on 1-5-2009) Burns, Simon. "China embracing 'illegal' VoIP calls". [online] Available at: http://www.itnews.com.au/News/47039,china-embracing-illegal-voip-calls.aspx (2007) (accessed on 1-5-2009) Fukuyama, N., Fugimoto, S. and Takenaka, M. "Firewall-friendly VoIpPSecure Gateway and VoIP Security Issues". Fujitsu Science and. Technology journal (2003) 39(2):182-187. 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