Things that slow your PC down

You are install one CCTV Software in your Customer PC. During boot up a computer brand new from the store, and to revel in the galactic super-speed in which it loads. It’s another to keep it running at that same speed, especially after some months have passed.

There are many reasons why your computer isn’t running at its optimum. Fortunately, they’re all very easy to solve. Read on to find out what slows your PC down, and what you can do about it.

An overloaded startup
Most applications you install usually add themselves automatically to your Start Up folder. This results in a slower startup because of the time needed to load them all. If your computer used to boot at the speed of light, but now moves slower than an old lady at the zebra crossing, this might be your problem.

SOLVE THIS: by accessing the MSCONFIG command through your search bar or run application, heading to the Startup tab at the top, and unchecking all unnecessary programmes. Seriously, do you really need iTunes to boot whenever you start your computer?

Too many temporary files
Whenever you look at webpages, watch videos, look at photos or even type on Microsoft Word, your computer stores temporary files so that it can load up faster the next time round. These files build up over time and may slow your computer down, especially since they’re usually located in your OS drive.

SOLVE THIS: By running Windows Disk Cleanup, found in Accessories, regularly.

A fragmented disk
A very old school problem, but still a very real one. Disk fragmentation occurs when the file system can’t or won’t allocate enough continuous space to store a complete file. This results in gaps within that file, and can make that file run slower than it usually would. Sometimes, those gaps occur when the OS deletes a file it doesn’t need any more. (This is safe though, your OS is smarter than you think).

SOLVE THIS: By running the Disk Defragmenter, also found in Accessories, regularly. We suggest not using the computer whilst the Defragmenter runs so as to minimise more fragmentation 

Programs uninstalled improperly
What a mouthful this header is. A PC does not work like a MAC – simply deleting the application you don’t want won’t cut it, and leaves behind remaining files that may cause your computer to slow down.

SOLVE THIS: By always uninstalling programs with the proper uninstall.exe, or remove them via the Control Panel. Go one step further to delete leftover files from the folder manually after uninstallation. This could include save games, 3rd party add ons, screenshots and etc.

A full OS disk
Many people make the mistake of saving everything possible into their C:/ drive, and that usually hosts their OS, or operating system. Once that drive gets too full, it slows down, thereby slowing down your entire computer’s processing speed.

SOLVE THIS: by partitioning your drive into C:/ and D:/ and saving your data in D:/. The lack of strain on your OS drive will let it run faster. You might be pleasantly amazed at the difference this can make.

Background anti-viruses
Anti-viruses are always helpful, but can sometimes do more harm than good. Since they’re always running and usually boot together with your computer, they can slow down processes considerably. Strangely enough, it’s always the ones you’ve got to pay for that wreak the most havoc.

SOLVE THIS: By disabling auto scans and updates, or by switching to a more lightweight, freeware anti-virus. Some have suggested Avira and AVG Antivirus, but it’s your job to ask your trusted geek friend what he’s using.

Spyware and viruses
Malicious software often heads straight for your Windows Registry or core file system, slowing down your computer. They can sneak in with applications you download online and install, and can also hop in from less-than-savoury websites you visit.

SOLVE THIS: While spyware and viruses can be removed manually by deleting them from your registry, some can be more persistent. In this case, use an automatic spyware remover – tons are available if you do a Google search. One of the more popular one is Ad-Aware Spyware Remover.

--Thanks to Maryanne Lee to provide info.

Door Monitoring and Control with Internet CCTV

Because internet CCTV cameras are intelligent, as opposed to the “dumb” traditional CCTV cameras, you can use them to see your property from wherever you are in the world, over the internet.  That, however, is just the start.  By joining these cameras to simple alarm and control circuits, they can be used to monitor and control doors.  In part one of this two-part series, I will show you how the monitoring side of the equation works.

Seeing your home, business or family from the other side of the world is amazing enough, but wireless internet CCTV cameras can do so much more than even this impressive feat.  Most of the best of this type of camera will have a digital input/output port, or I/O port, that allows the camera to be connected to electrical circuits.  The two input connectors on the port can be used to monitor an alarm circuit and trigger an alarm as I will explain.

The input connectors can be wired to each end of a so-called alarm circuit that in reality is nothing more than an unbroken loop of low-voltage wire, connected to, say, a pair of magnetic door contacts.  These are a standard part of any alarm system, but for those of you who have not come across them, you basically get two magnets, with plastic mounts.  One of them has connectors for the two wires of the alarm circuit.  You screw this one with the wires to the door frame, and the other one to the opening door so that they are lined up very close to each other when the door is closed, which keeps the circuit unbroken.  This is known as a “normally closed” or “NC” circuit, because in its normal state, the circuit is complete or closed.  When the door is opened, the magnetic contacts separate and the circuit is broken.

The wireless internet CCTV camera will detect when the circuit is broken because there will be a change in voltage at the input connectors and the camera is programmed to raise the alarm when this happens.  So, when the door is opened your camera can send an immediate message across the internet to a central computer.  This computer is programmed to send a text message to your mobile phone, and perhaps an email too – all within seconds of the door being opened.  Of course, if you want this great feature without “getting your hands dirty”, you will need a specialist “internet CCTV” company that can provide you with a camera pack ready-configured to work with your alarm circuit, so you can just plug it in.

We looked at how your wireless internet CCTV camera can monitor the area in front of an external door, and raise an alert when someone approaches the door.  In this final part of the series we are going to look at the next step in the process; how to use your camera to unlock the door.

You may remember from part one that most good quality internet CCTV cameras have a digital input/output port, or I/O port.  This is simply a series of connectors that allow the camera to be attached to electrical circuits.  I have shown you in part one how the two input connectors on the port can be used for monitoring an alarm circuit and raising an alert.  In a similar way, the two output connectors can be used to switch electrical equipment.  Your camera can be configured so that a current is sent to the output connectors under certain circumstances.  This gets very interesting, because unbelievably you can use the camera to actually open the door! So how can a wireless CCTV camera actually open a front door?  I will explain how in the next few sections.

The first piece of equipment you will need is an electronic door release, which you fit to the door frame.  This is a common piece of equipment in home and business security systems and can be obtained inexpensively by searching for “electronic door release” on the internet.  The door release is fitted to the door frame so that the catch on the door lock fits into it.  The door lock is untouched and the door can be unlocked with a key as usual, but the electronic door release can also open the door.  It does this by freeing the catch from the door frame without unlocking the lock, when a current is sent along the attached wires.

The next step is simply to run the wires from the door release mechanism to the output connectors on the internet CCTV camera’s I/O port. The camera has to be programmed so that it will accept an “open door” text message from your mobile phone or from a web page, and send a current to release the door.  Of course, you may be happy enough fitting the door release mechanism, but programming the camera to work with it is a specialist task.  I always recommend getting in touch with an “internet CCTV” provider for a ready-programmed camera that you simply plug in, so you get this great feature without needing any technical knowledge.

Once you have everything connected, here is how it all works in practice.  Let’s say you get a text message alert from the camera to tell you that someone is at the door, and you know it’s about the time your son gets home from school.  You log in using your mobile phone or PC and see a live picture of your son standing outside the front door, unable to get in because he’s forgotten his key.  You can simply send a text message from your phone to a central number, with your password, user name and a simple command such as “open front door”.  A central computer program gets your text message and processes it, checking your credentials.  Then, the system sends a message across the internet to your internet CCTV camera, and the camera then sends a current to the door release mechanism, which opens the door for your son, all within a few seconds!

New applications for wireless internet CCTV such as door monitoring and control bring the technology to a different level when compared to traditional CCTV.  This is yet another reason why these intelligent digital cameras are fast replacing dumb analogue cameras the world over.

TCP VS UDP & IP Topics

Can you explain the difference between UDP and TCP internet protocol (IP) traffic and its usage with an example?
A. Transmission Control Protocol (TCP) and User Datagram Protocol (UDP)is a transportation protocol that is one of the core protocols of the Internet protocol suite. Both TCP and UDP work at transport layer TCP/IP model and both have very different usage.

Difference between TCP and UDP

TCP	UDP
Reliability: TCP is connection-oriented protocol. When a file or message send it will get delivered unless connections fails. If connection lost, the server will request the lost part. There is no corruption while transferring a message.	Reliability: UDP is connectionless protocol. When you a send a data or message, you don't know if it'll get there, it could get lost on the way. There may be corruption while transferring a message.
Ordered: If you send two messages along a connection, one after the other, you know the first message will get there first. You don't have to worry about data arriving in the wrong order.	Ordered: If you send two messages out, you don't know what order they'll arrive in i.e. no ordered
Heavyweight: - when the low level parts of the TCP "stream" arrive in the wrong order, resend requests have to be sent, and all the out of sequence parts have to be put back together, so requires a bit of work to piece together.	Lightweight: No ordering of messages, no tracking connections, etc. It's just fire and forget! This means it's a lot quicker, and the network card / OS have to do very little work to translate the data back from the packets.
Streaming: Data is read as a "stream," with nothing distinguishing where one packet ends and another begins. There may be multiple packets per read call.	Datagrams: Packets are sent individually and are guaranteed to be whole if they arrive. One packet per one read call.
Examples: World Wide Web (Apache TCP port 80), e-mail (SMTP TCP port 25 Postfix MTA), File Transfer Protocol (FTP port 21) and Secure Shell (OpenSSH port 22) etc.	Examples: Domain Name System (DNS UDP port 53), streaming media applications such as IPTV or movies, Voice over IP (VoIP), Trivial File Transfer Protocol (TFTP) and online multiplayer games etc

Further readings

UDP is the faster protocol as it doesn't wait for acknowledgement so it is not at all having reliability as  compared to TCP.

Bridging the Analog-IP Gap

The name "encoder" does not really do these technological miracles justice. These investment-protecting, budget-saving marvels build a bridge between two generations of surveillance technology and bring harmony to your network.

IP-based video surveillance systems bring many important benefits. The image quality they deliver is a vast improvement. The networks are more scalable and cheaper to run. Better still, computerization means you can automate systems to bring about event management and intelligent video. Nevertheless, it is too early to claim that this development has rendered analog CCTV surveillance systems obsolete.

One option to installers would be to replace everything analog. This would mean getting rid of the existing analog cameras, the coaxial cables that have been laid inside and outside the buildings, the recording systems (AVRs or DVRs) and the management system. It would then be necessary to introduce an entirely new Ethernet cabling infrastructure, which would involve not insubstantial disruption, along with new IP-compatible storage hardware and a management system suited to IP or network video.

In many cases, that would be a waste of time and money, and the people who bought analog systems are not going to write off their investment any time soon, especially when around 95 percent of the estimated 40 million surveillance cameras installed in the world are still analog.

While analog technology is being fast eclipsed by IP video, which is growing at 30 percent a year according to IMS Research, there is no reason why the two infrastructures cannot be rationalized together, apart from a few technological hurdles. These barriers to integration are, in most cases, easily surmountable.

For most installations, the most valuable service you can offer your clients is to migrate them from analog to IP video by making judicious use of their existing network. The key to this magic passage is the video encoder. Encoders help convert analog networks into IP-friendly formats, putting the existing investment in cameras and coaxial cable to good use.