VoIP - What is the Problem?

Written by E. B. Randall


Inrepparttar beginning, whenrepparttar 143579 Internet Protocol was first designed, no one was thinking aboutrepparttar 143580 possibilities of sending audio and video. Real time communication was not an issue.

Perhapsrepparttar 143581 greatest single problem is thatrepparttar 143582 Internet Protocol (the IP part of VoIP - Voice over Internet Protocol) wasn't designed to ensure thatrepparttar 143583 packets are delivered inrepparttar 143584 correct order. When information is transmitted using IP,repparttar 143585 data is broken up into information packets, each of which is sent separately. The correct sequence of packets is part ofrepparttar 143586 information in each packet, but nothing specifically exists to make sure thatrepparttar 143587 packets are delivered, and, therefore, received inrepparttar 143588 proper order.

Now this isn't usually a significant issue for web pages, email, etc. Why? Because these aren't real-time applications. Audio and video however, especially live audio and live video are definitely real-time applications. For a real time conversation to work,repparttar 143589 packets have to arrive - pretty much in order and also within certain time limits.

The first, and one ofrepparttar 143590 major challenges then, is to restructure incoming packets intorepparttar 143591 correct order and to somehow cope with lost and/or trashed packets. Face it,repparttar 143592 internet does not provide a quality of service guarantee. If enough packets are lost, an audio or video stream rapidly turns into a useless mess. While packets can be resent -repparttar 143593 standard way lost/trashed packets are dealt with - real time communication means that you just can't wait around forever. After a certain time, it's simply too late to maintain a coherent stream.

What we've seen overrepparttar 143594 last few years is a gradual and now nearly explosive growth inrepparttar 143595 use of VoIP, and streaming audio and video. The reason is decline of dial-up andrepparttar 143596 growth of ISDN, DSL, ADSL, cable and other high speed, high bandwidth access modes. Bandwidth isrepparttar 143597 answer to most ofrepparttar 143598 problems posed by IP. End-to-end high speed links can ensure high quality sound. The sole remaining problem is latency.

Mobile devices security

Written by Mike Ber


As this security solution is not such a great idea, other companies have researched, and finally found a new way to prevent cell phones and PDAs theft. This method permits to remotely disable up to four different tasks of a stolen cell phone or PDA, rendering it inoperable. But atrepparttar same time data contained inrepparttar 143265 device are locked. The beauty of this option is thatrepparttar 143266 unit is not damaged in any way - full functionality and data can be easily restored ifrepparttar 143267 device is recovered. Thus,repparttar 143268 device is useless torepparttar 143269 thief, but it can be reactivated and restored if it is recovered and returned to its rightful owner.

Another new security breach has been encountered this year when reports were received about a backdoor Trojan horse program that can take control over a mobile device. This isrepparttar 143270 first known backdoor Trojan horse for PDAs. The subject program, identified as Backdoor.Brador.A, attacks PDAs runningrepparttar 143271 Windows operating system. And like all backdoors, it cannot spread by itself. The Trojan arrives as an e-mail attachment or can be downloaded fromrepparttar 143272 Internet. Also, it has a complete set of destructive functions characteristic for backdoors. After it is installed, this small program is activated whenrepparttar 143273 PDA is restarted and begins to look for a remote administrator to take control ofrepparttar 143274 device. Security specialists claimrepparttar 143275 virus was written by a Russian virus coder since it was attached to an e-mail with a Russian sender address and contained Russian text. Fortunately,repparttar 143276 Trojanís threat control and removal was rated as "easy".

The important thing about this virus is notrepparttar 143277 number of devices affected, because this number is very small, butrepparttar 143278 fact that this isrepparttar 143279 first one that appeared onrepparttar 143280 "market" is considered to be very important. We have to admit that it is hardly surprising that viruses have found their way to mobile devices. This isrepparttar 143281 natural trend. Where technology goes, viruses will follow. Asrepparttar 143282 new technology shifts intorepparttar 143283 mobile market, these threats will move in that direction also. The specialists fromrepparttar 143284 Kaspersky Labs claim they were expecting a virus attack on a PDA, due torepparttar 143285 latest attacks against other mobile devices. Now,repparttar 143286 PDA users look at a real danger and it is a well known fact that interested intruders will grabrepparttar 143287 chance to attack PDAs and mobile phones inrepparttar 143288 near future. Virus threats development for mobile devices is passing throughrepparttar 143289 same stages asrepparttar 143290 one for desktops.

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