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The Internet is undoubtedly the most significant development in communications technology over the past 25 years. It is also one of the most misunderstood, subject as it is to both disinformation and scaremongering.

Benefits to be realised from the World Wide Web are clear. Reduced communication costs, the ability for consumers to remove the middleman from transactions and access to huge amounts of facts, figures and information on all manner of topics being but a few. However, those benefits also bring challenges. How secure is the Internet? How reliable is it? What happens when things go wrong?

Security managers need to understand the principles of how alarm transmission may be achieved effectively over the Internet. By employing techniques more sophisticated than those systems which communicate over telephone lines, the Internet delivers a better, more cost-effective alarm service.

To help managers in their ongoing quest for knowledge and understanding, and as a follow-on from an earlier article discussing the basics of IP alarm monitoring technology (鈥楽ending out the signals鈥�, SMT, April 2004, pp21-22), we鈥檝e decided to list several of those questions most commonly-asked by security managers and offer them some salient answers.

鈥淚鈥檝e already spoken to my IT Department about IP signalling and didn鈥檛 really achieve anything. Why should that not be the case now?鈥�

The main reason why the IT Department will speak to you now is cost savings. In the majority of corporate blue chips, it鈥檚 the IT Director who pays for your company鈥檚 communication costs.

At present, your security system(s) will be using a telephone line to transmit alarms to the monitoring station. The cost of telephone line rental, alarm monitoring and line monitoring is around the 拢400 per annum mark per site (for a single path system).

By using IP technology, these annual ongoing costs are likely to be reduced by something in the region of 50%. Those savings could then be used to invest in GSM or GPRS dual path technology, consequently helping to deliver a better system and a safer environment for key holders.

鈥淪ometimes, when I connect to a web page on the Internet 鈥� such as a popular news site 鈥� the page takes a long time to appear. The Internet can be a bit slow, can鈥檛 it? Surely that must then affect the transmission time of my alarm system?鈥�

Services such as BBC News are offered to the user (in this case yourself) by way of a powerful master computer, otherwise known as a server. That server will have a certain capacity in terms of how quickly it processes your request for information (your click onto a link, for example). The bottleneck is the server鈥檚 ability to respond to you, not the Internet transmission path.

The BBC News home page and similar sites are accessed by thousands of people each day, and deliver an excellent service. The alarm transmission system that鈥檚 based on IP will normally have its communications server based at the monitoring station (which is clearly not a publicly-used service). The server is designed to respond immediately to the transmission requirements of the alarm system.

鈥淣ow and again I cannot access my e-mail or other tools that I use on our corporate network. Occasionally, our computer network isn鈥檛 available. Surely, then, the alarm system will not work?鈥�

The computer that you use at work talks to a server on the network that controls many of the resources you need day in, day out (such as e-mail). The fact that you cannot access an e-mail or other applications for a specific period of time doesn鈥檛 mean that the computer network has failed.

Indeed, whenever you cannot access your corporate e-mail, it鈥檚 almost certain that during the period you are restricted from working you may well look at the Internet for inspiration or research purposes while the 鈥榥etwork鈥� is put back to rights.

In practical terms, the loss of service that you are experiencing is a problem with the server on your local network. Your alarm transmission system that uses the network to send alarm traffic has no need to communicate with the server, and isn鈥檛 affected by its temporary (and normally infrequent) departure from service.

鈥淭here are sophisticated hackers using the Internet. They will be able to view all of my alarm transmission data and compromise the system. True or false?鈥�

Data transmission from the alarm system may be encrypted using sophisticated yet standard techniques.

Clearly, if the risk is high enough there may be an attempt to hack into the encryption algorithm and look at the data. However, the encryption standards used today are employed by Governments to send non-classified information over public networks. These encryption techniques are updated and calculated to take many decades of 鈥榤an effort鈥� in order to crack them.

鈥淚鈥檝e heard about 鈥楧enial of Service鈥� attacks, whereupon hackers flood your computer system so that nothing on the network can operate. Clearly, this will prevent the alarm transmission system from working over the Internet鈥�

Denial of Service attacks will affect an alarm transmission system. The latest standards for intruder alarm systems (PD6662) and CCTV systems (BS 8418) define how the alarm transmission system should identify failures and attacks.

A compliant system will notify the monitoring station within three minutes of any such attack, or IP route failure enabling remedial action (such as key holder or police response).

鈥淢essages can be lost on the Internet. If an alarm event disappeared into the ether, or was redirected by a malicious hacker, then the system is useless. Isn鈥檛 it?鈥�

The Internet is used daily by millions of people worldwide for e-mail traffic, stock updates, live auctions and a great many other real-time applications. Clearly, an alarm transmission is an event that simply must be delivered.

By confirming delivery of information from the alarm system back to the transmitter, very reliable alarm transmission over the Internet is achievable. Additionally, should the Internet connection have failed, or if there鈥檚 a malicious attack, then a good security alarm transmission system will have an alternative monitoring station location for automatic connectivity, or alternatively wireless back-up connection (for example GSM or GPRS).

鈥淚f I have to have GSM or GPRS as a dual path to the system, surely the costs will be very high? Maybe my risk isn鈥檛 high enough to justify the system?鈥�

Alarm transmission systems are a 鈥榤ust have鈥� for producing a solid, reliable solution to monitoring premises that require police response and/or insurance cover. It doesn鈥檛 matter whether the system adopted uses a standard telephone line or an IP network to communicate with the monitoring station 鈥� single path solutions are vulnerable, and render your key holding staff vulnerable, too. Security managers take note!

Today鈥檚 mobile telephone network operators have excellent tariffs and SIMs. Annual contracts are now available for as little as 拢4.00 per month. There may be some messaging costs to pay, but as the system is to be used as a back-up for the primary path, costs are only incurred when the primary path has failed and there鈥檚 an alarm event to send.

鈥淚鈥檓 told that the alarm system cannot be placed on the network because too much bandwidth will be absorbed and affect our other computers. Is this true?鈥�

There are really two aspects to this. One is the transmission of signals from an intruder system, the other is transmission of CCTV. Intruder alarm signals are very small. A good comparison is that a signal from the alarm system is equivalent to that of a text message from a mobile phone 鈥� very short and of no genuine consequence to the network.

The bigger issue surrounds CCTV images. However, most CCTV/DVR systems are only monitored when an event has been triggered. IT Departments are always concerned about video on the network, as they believe transmission will be constant (using a lot of bandwidth and resources in the process). Clearly, there is a general misunderstanding here which needs to be clarified.

When transmitting, the CCTV system will require an amount of bandwidth, but most systems have the flexibility to throttle their bandwidth use. You should discuss with your IT Department your specific monitoring requirements and the amount of bandwidth available to you at particular times of the day.

鈥淐ommunication services such as ADSL and GPRS aren鈥檛 yet available everywhere, are they? Isn鈥檛 that a problem?鈥�

You鈥檝e probably read statistics from BT detailing their roll-out of ADSL on more than one occasion. The key message is that ADSL services 鈥� always on Internet connections 鈥� will be available in over 99% of exchanges by the end of 2005. BT is successfully rolling out ADSL connections to tens of thousands of customers each and every month.

With regard to GPRS, it鈥檚 a pretty similar story. GPRS services from O2 and Vodafone are high revenue generating tariffs 鈥� used by professionals on the road for downloading e-mails, accessing Internet updates and connecting to the corporate office. These services are highly successful, but in order to be so the coverage must be excellent.

鈥淥K. I鈥檓 sold on the concept of IP alarm monitoring. I can now go out and buy an IP interface for my alarm panel and begin transmitting, right?鈥�

The answer to this one is both a 鈥榊es鈥� and a 鈥楴o鈥�. Transmitting alarms over IP will require you to work with your IT Department and ensure that the right network security is in place to protect access to your corporate data.

Additionally, an IP module for your alarm panel will not in fact provide you with many of the requirements of PD6662 (such as suitable encryption, line monitoring or a dedicated wireless back-up path).

You need to consider all of those elements 鈥� as well as insurance requirements and the needs of the police 鈥� before buying a low cost IP transmission solution. Don鈥檛 just replace your Digi modem with an IP equivalent.

鈥淓ven though I鈥檓 sold on the idea, one thing is clear to me. I鈥檓 never going to understand everything about IP. What are the consequences of that?鈥�

You need to ask yourself how much you know about the existing systems you use and the way in which they operate. Understanding how a Digi modem really works, or how an ISDN line operates isn鈥檛 easy, but we accept the principles. It鈥檚 the same with IP.

You need to educate yourself on the basic principles, remove some of the fear inevitably generated by misinformation, misunderstanding or bad experiences and ensure that you partner with an installer and monitoring station that can assist you and work with your IT Department to deliver a cost-effective IP solution for alarm transmission and line monitoring.