RS422, RS485, comparison with RS232

RS232 is well-known due to popularity of today’s PC’s, unlike the RS422 and RS485. These are used in industry for control systems and data transfers (small volumes, less than hundreds of Mb/s).

So, what is the main difference between RS 232 and RS 422 & 485? The RS 232 signals are represented by voltage levels with respect to ground.

There is a wire for each signal, together with the ground signal (reference for voltage levels). This interface is useful for point-to-point communication at slow speeds. For example, port COM1 in a PC can be used for a mouse, port COM2 for a modem, etc. This is an example of point-to-point communication: one port, one device. Due to the way the signals are connected, a common ground is required. This implies limited cable length? About 30 to 60 meters maximum. (Main problems are interference and resistance of the cable.) Shortly, RS 232 was designed for communication of local devices, and supports one transmitter and one receiver.

RS422 & 485 uses a different principle: Each signal uses one twisted pair (TP) line-two wires twisted around themselves. We’re talking ‘Balanced data transmission’, or ‘Differential voltage transmission’. Simply, let’s label one of the TP wires ‘A’ and the other one ‘B’. Then, the signal is inactive when the voltage at A is negative and the voltage at B is positive. Otherwise, the signal is active, A is positive and B is negative. Of course, the difference between the wires A and B matters. For RS 422 & 485 the cable can be up to 1200 meters (4000 feet) long, and commonly available circuits work at 2.5 MB/s transfer rate.

What is the difference between RS 422 and RS 485? Electrical principle is the same both use differential transmitters with alternating voltages 0 and 5V. However, RS is intended for point-to-point communications, like RS 232. RS 422 is intended uses two separate TP wires, data can be transferred in both directions simultaneously. RS 422 is often used to extend a RS 232 line, or in industrial environments.

RS 485 is used for multiply-point communications: more devices may be connected to a single cable- similar to e.g ETHERNET networks, which use coaxial cable. Most RS 485 systems use Master/Slave architecture, where each slave unit has its unique address and responds only to packets addressed to this unit. These packets are generated by Master (e.g PC), which periodically polls all connected salve units.

Quick Comparison Chart:

Choose an HDMI Cable

How to Choose an HDMI Cable

Choosing an HDMI cable can be a complex task. There are several factors that must be considered in order to select the best HDMI cable to meet the user’s requirements:

·         HDMI standards compliance

·         HDMI Cable Categories

·         Cable length

·         Cable quality

·         Active cables

·         HDMI devices

·         Price

HDMI Standards Compliance

Each HDMI cable is rated to comply with a specific revision of the HDMI standards. A cable rated for HDMI 1.2a should meet the requirements of HDMI 1.0, 1.1 and 1.2, but is not guaranteed to meet the standards for HDMI 1.3.

HDMI Cable Categories

The HDMI standards define two cable categories. Category 1 HDMI cables support HDTV resolutions and frame rates. Category 2 cables are required for higher resolutions or higher frame rates.

Cable Length

The HDMI specification does not define a maximum cable length. HDMI cables are commonly available in 3′ to 50′ lengths.

Purchasing a cable longer than necessary will cost more money, but it will also increase signal loss due to attenuation.

Cable Quality

All other factors being equal, a cable that is built to higher tolerances using better materials will outperform a cable that is built merely to meet a standards specification. In addition, these premium cables will often provide longer service lives.

An HDMI cable can be made using 28 AWG wire, but a 24 AWG wire will create a sturdier cable that is more resistant to attenuation.

As with traditional analog stereo cables, premium HDMI cables are often furnished with gold plated connectors to ensure the best possible signal quality.

Active Cables

For specialized high end applications, some manufacturers are selling active HDMI cables. These cables use a variety of technologies that involve boosting the transmission distance or quality through the addition of electrical power to the cable connection.

Some of these active cables run over fiber optics or Cat-5 cable.

HDMI Devices

Another approach to supporting extremely long cable runs is to chain multiple HDMI cables together with amplifiers, repeaters, or equalizers.

Cyber Law in INDIA

Why Cyberlaw in India ? 

When Internet was developed, the founding fathers of Internet hardly had any inclination that Internet could transform itself into an all pervading revolution which could be misused for criminal activities and which required regulation. Today, there are many disturbing things happening in cyberspace. Due to the anonymous nature of the Internet, it is possible to engage into a variety of criminal activities with impunity and people with intelligence, have been grossly misusing this aspect of the Internet to perpetuate criminal activities in cyberspace. Hence the need for Cyberlaws in India.

What is the importance of Cyberlaw ? 
Cyberlaw is important because it touches almost all aspects of transactions and activities on and concerning the Internet, the World Wide Web and Cyberspace. Initially it may seem that Cyberlaws is a very technical field and that it does not have any bearing to most activities in Cyberspace. But the actual truth is that nothing could be further than the truth. Whether we realize it or not, every action and every reaction in Cyberspace has some legal and Cyber legal perspectives.

Does Cyberlaw concern me ? 
Yes, Cyberlaw does concern you. As the nature of Internet is changing and this new medium is being seen as the ultimate medium ever evolved in human history, every activity of yours in Cyberspace can and will have a Cyberlegal perspective. From the time you register your Domain Name, to the time you set up your web site, to the time you promote your website, to the time when you send and receive emails , to the time you conduct electronic commerce transactions on the said site, at every point of time, there are various Cyberlaw issues involved. You may not be bothered about these issues today because you may feel that they are very distant from you and that they do not have an impact on your Cyber activities. But sooner or later, you will have to tighten your belts and take note of Cyberlaw for your own benefit.

Cyberlaw Awareness program 
Are your electronic transactions legally binding and authentic? Are you verifying your customers' identities to prevent identity theft? Does your online terms and conditions have binding effect? Are you providing appropriate information and clear steps for forming and concluding your online transactions? How are you ensuring data protection and information security on your web site? Are you recognising the rights of your data subjects?

Transacting on the Internet has wide legal implications as it alters the conventional methods of doing business. To build enduring relationships with your online customers the legal issues of e-transactions need to be addressed from the onset.

This Awareness program will cover
the basics of Internet Security
basic information on Indian Cyber Law
Impact of technology aided crime
Indian IT Act on covering the legal aspects of all Online Activities
Types of Internet policies required for an Organization.
Minium hardware and software, security measures required in an organization to protect data

Cyber laws are meant to set the definite pattern, some rules and guidelines that defined certain business activities going on through internet legal and certain illegal and hence punishable . The IT Act 2000, the cyber law of India , gives the legal framework so that information is not denied legal effect, validity or enforceability, solely on the ground that it is in the form of electronic records.

One cannot regard government as complete failure in shielding numerous e-commerce activities on the firm basis of which this industry has got to its skies, but then the law cannot be regarded as free from ambiguities.

MMS porn case in which the CEO of bazee.com(an Ebay Company) was arrested for allegedly selling the MMS clips involving school children on its website is the most apt example in this reference. Other cases where the law becomes hazy in its stand includes the case where the newspaper Mid-Daily published the pictures of the Indian actor kissing her boyfriend at the Bombay nightspot and the arrest of Krishan Kumar for illegally using the internet account of Col. (Retd.) J.S. Bajwa.

The IT Act 2000 attempts to change outdated laws and provides ways to deal with cyber crimes. Let’s have an overview of the law where it takes a firm stand and has got successful in the reason for which it was framed.

1. The E-commerce industry carries out its business via transactions and communications done through electronic records . It thus becomes essential that such transactions be made legal . Keeping this point in the consideration, the IT Act 2000 empowers the government departments to accept filing, creating and retention of official documents in the digital format. The Act also puts forward the proposal for setting up the legal framework essential for the authentication and origin of electronic records / communications through digital signature.

2. The Act legalizes the e-mail and gives it the status of being valid form of carrying out communication in India. This implies that e-mails can be duly produced and approved in a court of law , thus can be a regarded as substantial document to carry out legal proceedings.

3. The act also talks about digital signatures and digital records . These have been also awarded the status of being legal and valid means that can form strong basis for launching litigation in a court of law. It invites the corporate companies in the business of being Certifying Authorities for issuing secure Digital Signatures Certificates.

4. The Act now allows Government to issue notification on the web thus heralding e-governance.

5. It eases the task of companies of the filing any form, application or document by laying down the guidelines to be submitted at any appropriate office, authority, body or agency owned or controlled by the government. This will help in saving costs, time and manpower for the corporates.

6. The act also provides statutory remedy to the coporates in case the crime against the accused for breaking into their computer systems or network and damaging and copying the data is proven. The remedy provided by the Act is in the form of monetary damages, not exceeding Rs. 1 crore($200,000).

7. Also the law sets up the Territorial Jurisdiction of the Adjudicating Officers for cyber crimes and the Cyber Regulations Appellate Tribunal.

8. The law has also laid guidelines for providing Internet Services on a license on a non-exclusive basis.

The IT Law 2000, though appears to be self sufficient, it takes mixed stand when it comes to many practical situations. It looses its certainty at many places like:

1. The law misses out completely the issue of Intellectual Property Rights, and makes no provisions whatsoever for copyrighting, trade marking or patenting of electronic information and data. The law even doesn’t talk of the rights and liabilities of domain name holders , the first step of entering into the e-commerce.
2. The law even stays silent over the regulation of electronic payments gateway and segregates the negotiable instruments from the applicability of the IT Act , which may have major effect on the growth of e-commerce in India . It leads to make the banking and financial sectors irresolute in their stands .
3. The act empowers the Deputy Superintendent of Police to look up into the investigations and filling of charge sheet when any case related to cyber law is called. This approach is likely to result in misuse in the context of Corporate India as companies have public offices which would come within the ambit of "public place" under the Act. As a result, companies will not be able to escape potential harassment at the hands of the DSP.
4. Internet is a borderless medium ; it spreads to every corner of the world where life is possible and hence is the cyber criminal. Then how come is it possible to feel relaxed and secured once this law is enforced in the nation??

Seven Advantages of IP or Network Camera Surveillance System

Seven Advantages of IP / Network Camera Surveillance System

1, the advancement: system use existing integrated wiring network transmission of images, and real-time surveillance. The system front-end equipment, attachment is concise, the back-end and only a set of software system.

2, reliability: the main equipment of WDR PoE network IP camera adopted embedded real-time operating system, the required equipment is simple, and image transmission is implemented through integrated wiring network, the reliability of the system is high.

3, price performance ratio: the required equipment system is extremely simple, system control by the backend software system implementation, eliminating the traditional analog surveillance system of a large number of devices, as a result of the image transmission through the network integrated wiring, saves a lot of video coaxial cable, reducing the cost.

4, security: system set up different levels of user permissions, only the highest authority of the user to set or change to the whole system, without permission of the user is receiving less than the image.

5, easy maintenance: the 3 megapixel waterproof IR h.264 CMOS IP camera installation of the system is simple, installation and use of the software system is also very simple. In the aspect of maintenance, system wiring is very simple, and the reliability of the main equipment is very high, maintain good performance, and can realize remote maintenance.

6, easy extension: when the need to increase surveillance points, surveillance host, only need to add 3MP outdoor vandalproof HD wdr dome camera can be through the existing network, without the need to change existing wiring system what to do.

7, wide range of application: using the network transmit real-time image, such as office, building inter-district remote surveillance: chain business, large factory room, the distal child care for the elderly, public building, there is no dangerous environment surveillance, surveillance, traffic regulation of all financial institutions branch, false alarms distinguishing, etc.

Principles of Surveillance System Installation

8 principles surveillance system installation

Safety awareness increases, Video surveillance systems into our lives. Video surveillance program are also more and more, So the first thing to consider installing surveillance systems of the following 8 major principles:

1.Real-time monitoring system

Real-time monitoring is very important, and it’s necessary for the Monitoring System.

2.Security

Security and confidentiality measures to prevent the illegal invasion and illegal operation system.

3.Scalability

Monitoring system equipment used modular structure, The system can be extended no need to change the structure of the network and hardware and software.

4.Openness

The system provides software, hardware , communications, networking , operating systems and database management systems and other aspects of the interface and tools that meet international standards , so that the system has good flexibility , compatibility , scalability and portability.The entire network is an open system that is compatible with a number of monitor manufacturers of products, and to support the secondary development.

5.Normative

Equipment and technology used in line with internationally accepted standards.

6.flexibility

System features full use of existing video surveillance subsystem networks. Monitoring can be used in different business, it is full-featured and easy to configure.

7.Advancement

Monitoring systems will become an advanced , future-proof , high reliability, confidentiality, easy network expansion , strong connection data processing capabilities, the system is running manipulate simple security system .

8.Applicability

Video surveillance systems have to complete the project in the required functional capacity and standards. Comply with the requirements of norms of domestic and foreign, and the advantages include ease of operation, Low- cost and high-performance.

PTZ camera advantages & Disadvantages

PTZ camera advantages & Disadvantages

PTZ cameras occupy a special place in the field of video surveillance. So, here’s an article which will throw some light on how these cameras can prove useful, what are their deployment pros and cons and other related points.

Basically, a PTZ security camera is a network camera which reflects the movement options of Pan, Tilt and Zoom. These cameras can be mechanically operated, where the user typically has the ability to control the Pan-L and R (Rotate Vertically); Tilt- Up & down (Move Horizontally); and Zoom (Point Down an objects) of the camera with a joy stick / Key Board / hardware device or another software.

PTZ cameras are ideal choice for monitoring large public places like stadiums, traffic signals, and other environments. If these cameras come tucked with the feature of megapixel or high definition (which is now possible in 2015), then they add absolute value to the whole deployment security surveillance.

Coming to the Pros and Cons of PTZ cameras, here’s a bit of illustration-

PTZ camera advantages

1. With the help of a capable VMS, the PTZ cameras can be auto programmed. So, these cams can capture the front doors, the gate and the fence at regular intervals and can achieve the best out of it.

2. If the video from this camera is under live monitoring then an operator can track down a suspect or respond to a threat triggered by the video management software integrated with the camera. The operator can then zoom-in and take control of the situation and if necessary can act in time for loss prevention. If the PTZ camera is tucked with high definition, then the captured image can help the operator track the facial features of a suspect, license plate of an automobile involved in crime or identify an object of interest.

3. As these security cameras can be panned, zoomed and tilted, hundreds of acres of land can be monitored day/night. So, by using a PTZ in premises, the cost of coverage per given area can get reduced.

PTZ camera Disadvantages

1. As every technology has its pros and cons, so does the PTZ camera. Generally, people gather an opinion that these cameras are capable of covering 360 degrees. Except for a couple of cameras available in the market of this sort none can truly cover up more than 180 degrees. So, go for a demo if the camera PTZ maker claims to make a camera with not just 360 degrees coverage.

2. The other disadvantage which can prove advantageous to criminals is that these cameras record where the lens is focused. So, if an incident occurs and if the camera is pointed in other direction, then it could potentially miss the event entirely and this could miss vital video evidence.

3. Though, there is a lot of development in PTZ cameras offered by different manufactures, it is often observed that they need to be regularly maintained and have a shorter life span. Moreover, most installers feel that in hot conditions, these cameras will give-up. But yes, if they are secured in a housing which keeps the inside temperature under control, then these cameras tend to work fine.

4. The sensors of PTZ cameras are smaller when compared to fixed cameras. So, image quality is not up to the mark. But as technology improvisation is taking place is this segment, it is reviewed to be yielding better results.

5. To get the best out of a PTZ camera monitoring, a live operator dedicated to monitor the system is needed. So, here a rise in surveillance costs can be observed.

6. If the PTZ camera is not properly installed, then a slight wind can push the video output into doldrums. So, the installer must be very careful in such camera deployments.

7. PTZ cameras if positioned in unwanted places can land the installer and the owner installing the equipment into legal trouble. And if their focus includes the coverage of an opposite house swimming pool or lawn even by an inch, then the installer and the related authorities will be in deep trouble.

8. PTZ controls are sensitive to latency and if the latency is more than a fraction of second, then the PTZ control can go out of gear.

9. PTZ cameras have more features in them and so their cost is 60% high than normal fixed cameras.

10. The position of a PTZ camera will indicate the focus of its lens. So, an attacker can creep into the blind spot of the camera and spray some paint on the camera lens, in order to prevent the camera from recording further. There is a high chance that the image of the person doing such mischief can get skipped.

Therefore, in order to get optimal results from PTZ camera deployment these cameras can be made as a supplementary with fixed cameras for investigating a situation or tracking a criminal.

Hope, this article helps in unraveling the truth about PTZ security cameras.

720p and 1080p explained

720p explained

720p is the shorthand name for a category of HDTV video modes. The number 720 stands for the 720 horizontal scan lines of display resolution (also known as 720 pixels of vertical resolution), while the letter p stands for progressive scan or non-interlaced.

Progressive scanning reduces the need to prevent flicker by filtering out fine details, so sharpness is much closer to 1080i than the number of scan lines would suggest. A 720p frame has about 1 million pixels. Compared to it, a 1080p frame has 2 million pixels so the amount of detail doubles. However in practice the difference between 1080p vs 720p is not as obvious as the one between standard definition vs high definition (480p vs 720p). For example a regular DVD isn’t even considered high definition because it is either 720×480 (NTSC) or 720×576 (PAL) but it looks much better than regular NTSC or PAL TV broadcasts and not as great as 720p. That being said, you do get more detail from 1080p than from any resolution if you have the “winning” formula for screen size, resolution and viewing distance – that is if you have the optimum conditions to get the most out of 1080p.

1080p explained:
The number 1080 represents 1,080 lines of vertical resolutions (1,080 horizontal scan lines), while the letter p stands for progressive scan (meaning the image is not interlaced). 1080p can be referred to as full HD or full high definition although 1080i is also “Full HD” (1920×1080 pixels). The term usually assumes a widescreen aspect ratio of 16:9, implying a horizontal resolution of 1920 pixels. This creates a frame resolution of 1920×1080, or 2,073,600 pixels in total.

The only pure 1080p content comes from high definition DVDs like Blue Ray and HD DVD. Regular DVDs are way below that, having just 480p or 576p. You also get HD content from TV broadcasts but for now only 1080i and 720p. Basically 1080i offers pretty much the same amount of detail as 1080p but the quality of fast moving scenes is a bit inferior to 1080p. To understand this better read the 1080p vs 1080i guide. 720p content will of course look the same (or very similar) on a 1080p screen as it does on a 720p screen because what also matters is the content resolution not just the screen resolution.

Here is a sample with the difference between 720p and 1080p:

480i - Total image resolution 337,920 pixels

480p - Total image resolution 337,920 pixels

720p - Total image resolution 921,600 pixels (roughly equivalent to a 1 mega pixel camera)

1080i - Total image resolution 2,073,600 pixels (equivalent to a 2 mega pixel camera)

1080p - Total image resolution 2,073,600 pixels (equivalent to a 2 mega pixel camera)

More lines is nice but don't forget about the 'p' and 'i' in the 720p, 1080i and 1080p. The letter is an abbreviation for the type of scan the TV uses -- 'p' stands for progressive and 'i' stands for interlaced.

1000BASE-TX over CAT 6

1000BASE-TX over Category 6

TIA/EIA-854 : A Full Duplex Ethernet Physical Layer Specification for 1000Mb/s operating over Category 6 Balanced Twisted Pair Cabling (1000BASE-TX).

This document specifies a full duplex Ethernet physical layer interface for 1000Mb/s operation over a 100 meters of a Category 6 twisted pair cabling channel, referred to as 1000BASE-TX.

The purpose of this document, 1000BASE-TX, is to provide an Ethernet physical layer specification that is low complexity and can easily be implemented by many vendors. This will take advantage of the improved transmission parameters provided by Category 6 cabling.

It was believed by the members of this project that a much simpler solution for data rates of 1000Mb/s operating over a 100 meters of Category 6 UTP cabling would be a benefit to users who migrate to the higher data rates. It would eliminate the complicated requirements in the 1000BASE-T standard of canceling the effects of crosstalk and return loss, providing a solution that could operate at a much lower power level, the potential for multiple ports per chip, and could be implemented at a lower cost.  As it turned out, the ports became cheap very quickly and so no hardware vendor adopted this standard.

ANSI decided not to adopt TIA/EIA-854. The IEEE also decided not to adopt this and keep with 1000BASE-T as in IEEE802.3ab.

Since there is no application for this limit and it was not adopted by either ANSI or IEEE, it is not in the DTX CableAnalyzer.

Make Your Internet Faster

How To Make Your Internet Faster (Windows XP, Vista, 7,8)

Slow internet connection is the annoying thing that many people don't want to have. If your internet download speed is slow or your internet connection took long time to load the page, so you are not viewing your Security Camera / DVR. Don't worry today we will teach you how to make your internet faster by change DNS server in the control panel. There are many tricks and tips that also can increase internet speed, but we will show you the effective one.

In here we will walk you through step by step on how to change DNS servers that can increase your internet speed to maximum. Make sure to follow the step correctly for better result.

Step 1 : Open Control Panel

Step 2 : Go to Network and Internet >>> Network and Sharing Center

Step 3 : Click on Local Area Connection >>> Select Properties

Step 4 : Find and double click on "Internet Protocal Version 4 (TCP/IPv4)"

Step 5 : Tick on "Use the following DNS server addresses"

Step 6 : Fill up the DNS server like the same down below :

Preferred DNS Server : 8.8.8.8 
Alternate DNS Server : 8.8.4.4

or

Preferred DNS Server : 208.67.222.222
Alternate DNS Server : 208.67.222.222 

Step 7 : Click OK and Restart your computer.

Cleaning Up Your Computer

No matter how fast your internet is, If there are a lot of junk files and temporary files in your system, Your internet speed and system performance will drop. Also, there are many program installed in your computer and running on the background, Those programs that running in the desktop can slow down your internet speed also.

If you have many junk files and unnecessary programs installed in your PC, you should delete them out of your system.

Scan For A Virus

Virus is a main problem that causes your fast internet to run slow. Running your system with a virus can slow down your system performance, decrease your internet speed, and cause many more problems. If there are virus in your system, make sure to scan and get rid of it. You should scan for your system once a week for better security.

Protect your home use Security Cameras

I want to protect my home and use Security Cameras

So I want to protect my home.   I need a video surveillance system for night or in areas with low light. So looks like the best option would be infrared security cameras that capture images even in the dark.

So what is an infrared camera exactly?

An infrared camera works by calculating the brightness of a room or particular area. They feature special LED lighting which can be seen on the outside lens. These LEDs are able to capture light from the regions of electromagnetic spectrum that allow an image to be created even if there is little visible light. For this reason we refer to IR cameras as having night vision.

An infrared security camera will switch its mode to infrared only when the light drops below a certain level. It captures black and white images at that point.

Interesting side note, IR Illuminators allow many objects to be penetrated, such as the haze, fog and smoke. Infrared Illuminators are used typically for a low light environment. Sometimes, when the IR array is focused narrowly or the hold is not strong enough the external IR Illuminator will give an extra sharp image. It can provide an additional infrared light source that is invisible to the naked eye normally.

If you are going to use infrared security cameras outdoors, the best option would be to choose those that can stand up to the natural elements as well as tampering from criminals.   I found several options that allow for the greatest flexibility including direct bright light, vandal resistant, weather proof and cost effective.