VoIP is a protocol (Voice-over-Internet protocol) which is designed to optimize the transmission of audio through the Internet. Most people refer to VoIP as the act of sending audio through a network, rather than the protocol itself. The protocol evolved from a 1973 protocol known as the Network Voice Protocol, which was one of the first attempts at sending speech over the Internet.
Despite the NVP's early origination date, it was not until 1996 that VoIP became widely available to consumers. Even then, the protocol and network structures had a long way to go, and the system was relatively inefficient. As technology has evolved and advanced, VoIP has become a realistic cost-effective solution to consider.
Currently, the chief alternative to VoIP is the PSTN, or public switched telephone network, which utilizes the traditional structure of circuit switching. The PSTN is a world network, much like the Internet, and includes household and mobile phones. When VoIP first came out, it was incompatible with PSTN, meaning users could only connect to other people with VoIP. Many early complications such as this have since been overcome, making VoIP much more viable than it was a decade ago.
What can VoIP do that the PSTN cannot One feature is the ability to add multiple phone lines without incurring additional costs, as it is possible to transmit several phone calls over the same connection. Other features that normally cost extra for a PSTN phone are free on VoIP; this includes attributes such as call forwarding, call waiting, caller ID. When encryption is employed, the security of the network is strong and hard to break in to.
The most popular security protocol used with VoIP is the Secure Real-Time Transport Protocol (SRTP). Many other services can be integrated with a system, including file exchanges, video conversation, and conference calls. Advanced services which would usually be difficult to implement are much easier to do in a VoIP system, and this ease also reduces the cost of installation as well.
Despite the many breakthroughs that have been made through the years, VoIP still faces many challenges. Audio is essentially large streams of data, and whenever data of that size is transferred through a network, problems can occur. Receiving nodes must restructure every bit of information that comes in, so if the data is obtained too quickly, the decapsulation process can be negatively affected.
Jitter, another data transfer conundrum, can also occur frequently if proper precautionary measures are not taken. All of the data transfer troubles, if not tended to, can result in a low quality of service. When packets are not received or they are scrambled, this translates into drop-outs of voice for the end users.
Reliability is another important thing to consider, especially for home use of VoIP. With regular telephones, if the power goes out, you can still use your phone. However, because VoIP works directly through the Internet, and a modem that uses household electricity, if the power goes out, your phone goes out.
Although VoIP can be made secure through encryptions, most of the software on the market today does not support that function. While SRTP is available for business applications, it rarely is accessible to the average consumer. For users who do not have any encryption mechanism, they can still rely on security by obscurity, which is usually fine enough for non-business uses.
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Imagine doing a 250-km journey in a car that will cover the distance in just one-litre of petrol (just over $1)!
That's exactly what students of a Technical Institute in Punjab - the Rayat Institute of Engineering and Information Technology near Ropar - claim to have developed.
"It is a rare solo car which can generate a mileage of up to 250 km per litre. Our team of students have not only achieved this feat, but are going to showcase it at a world super-mileage competition in the United States next month," Gurvinder Singh Bahra, vice chairman of the Rayat and Bahra group of institutes, told media persons here as he unveiled the 'wonder car' with the team.
Though the students' team claims that the car will cost Rs.500,000, its research and development cost over Rs.2.13 million to the institute.
The car, having a 92cc engine, has been developed by a seven-member team of students from the sixth semester of the institute's mechanical engineering course. The team is led by Gaurav Aggarwal as captain and other members are Mayank Tyagi, Bhavuk Makkar, Arun Salaria, Rahul Kumar, Ramandeep Singh and Navneet Kumar. The team had Jujhar Singh and Rajesh Chaudhary as faculty advisors.
It took them one year to develop the car, said Bahra.
The team is now headed for the world super mileage competition to be held in Michigan, US, next month. The competition is organised by the Society of Automotive Engineers in the US.
"We have modified the engine as per rules supplied by the competition organisers. The frame of the 65-kg car has been developed by using special grade aluminium. It has hydraulic disc brakes and a modified carburettor and fuel supply system. The car has a lightweight outer body shell with an aerodynamic structure.
"All safety and ergonomics features have been taken into account. The car even has a self-designed battery re-charging system," said Aggarwal.
The Rayat team will be the second Asian team to participate in the 28-year-old contest that will have competitors from 35 countries.
Friends we have to be very proud of this as Indians. Letz encourage them in all aspects and let them find more luxurious car with same mileage...
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Regards,
DJ
BALANCE SHEET OF LIFE
Our Birth is our Opening Balance
Our Death is our Closing Balance
Our Prejudiced Views are our Liabilities
Our Creative Ideas are our Assets
Heart is our Current Asset
Soul is our Fixed Asset
Brain is our Fixed Deposit
Thinking is our Current Account
Achievements are our Capital
Character & Morals, our Stock-in-Trade
Friends are our General Reserves
Values & Behavior are our Goodwill
Patience is our Interest Earned
Love is our Dividend
Children are our Bonus Issues
Education is Brands / Patents
Knowledge is our Investment
Experience is our Premium Account
The Aim is to Tally the Balance Sheet Accurately.
The Goal is to get the Best Presented Accounts Award.
Yum is a very powerfull package manager. yum will resolve dependencies for you and makes installing applications a breeze. yum also searches, removes, and lists packages for you.
Usage: yum [options] <>
Options:
-h, --help show this help message and exit
-t, --tolerant be tolerant of errors
-C run entirely from cache, don't update cache
-c [config file] config file location
-R [minutes] maximum command wait time
-d [debug level] debugging output level
-e [error level] error output level
-y answer yes for all questions
--version show Yum version and exit
--installroot=[path] set install root
--enablerepo=[repo] enable one or more repositories (wildcards allowed)
--disablerepo=[repo] disable one or more repositories (wildcards allowed)
-x [package], --exclude=[package]
exclude package(s) by name or glob
--obsoletes enable obsoletes processing during updates
--noplugins disable Yum plugins
--nogpgcheck disable gpg signature checking
--disableplugin=[plugin] disable plugins by name
From a first look this can look rather intimidating, but this is rather easy.
- Examples given below:
- To seach for a application
Yum will search all your enabled repos and tell you where you can obtain the package from
yum search application_name
- Yum can list all available packages from your enabled repos and tell you where you can obtain the package from:
yum list available
- To find out more info about some package
yum info application_name
- Installing applications
Inastalling is as easy as
yum install application_name
- Listing rpms
yum can list installed rpms for you from the repos you have enabled
yum list extras
- Removing rpms
Yum can remove a application and the dependenciesit installed with tat application. it will not remove depenencies if another application installed needs them.
yum remove application_name
- Updating the system
Yum can update the system for you with out user interact if you want it to.
yum update
- Not sure if you have upates?
yum check-update
- Local install
downloaded a rpm and cannot install it with rpm because of dependencies?
yum localinstall /path/to/the/rpm
- Happy yumming...
Once upon a time ...
There was a rich King who had 4 wives.
He loved the 4th wife the most and adorned her with rich robes and treated her to the finest of delicacies. He gave her nothing but the best.
He also loved the 3rd wife very much and was always showing her off to neighboring kingdoms. However, he feared that one day
she would leave him for another.
He also loved his 2nd wife. She was his confidante and was always kind, considerate and patient with him. Whenever the King faced a problem, he could confide in her to help him get through the difficult times.
The King's 1st wife was a very loyal partner and had made great contributions in maintaining his wealth and kingdom. However, he did not love the first wife and although she loved him deeply, he hardly took notice of her.
One day, the King fell ill and he knew his time was short.
He thought of his luxurious life and pondered, "I now have 4 wives with me, but when I die, I'll be all alone.
Thus, he asked the 4th wife, "I have loved you the most, endowed you with the finest clothing and showered great care over you. Now that I'm dying, will you follow me and keep me company?"
"No way!" replied the 4th wife and she walked away without another word.
Her answer cut like a sharp knife right into his heart.
The sad King then asked the 3rd wife, "I have loved you all my life. Now that I'm dying, will you follow me and keep me company?"
"No!" replied the 3rd wife. "Life is too good!When you die, I'm going to remarry!"
His heart sank and turned cold.
He then asked the 2nd wife, "I have always turned to you for help and you've always been there for me. When I die, will you follow me
and keep me company?"
"I'm sorry, I can't help you out this time!" replied the 2nd wife. "At the very most, I can only send you to your grave."
Her answer came like a bolt of thunder and the King was devastated.
Then a voice called out:
"I'll leave with you and follow you no matter where you go." The King looked up and there was his first wife. She was so skinny,
she suffered from malnutrition.
Greatly grieved, the King said, "I should have taken much better care of you when I had the chance!"
In Truth, we all have 4 wives in our lives ...
Our 4th wife is our body. No matter how much time and effort we lavish in making it look good, it'll leave us when we die.
Our 3rd wife is our possessions, status and wealth.When we die, it will all go to others.
Our 2nd wife is our friends. No matter how much they have been there for us, the furthest they can stay by us is up to the grave.
AND
And our 1st wife is our Parents ,often neglected in pursuit of wealth, power and pleasures of the ego.
However, our Parents are the only thing that will follow us and guide wherever we go.
So Love them at ur best ..... They need and Love you most !!!
You are their greatest gift
Let them Smile and Cherish..
Have u ever heard about LPG gas cylinder's expire date. I also didn'tknow.
How to find LPG cylinder's expiry date
Very important information.
Most of us do not know this. I came to know today from the gas
stockist, because here one accident occurred.
Do you know that there is an expiry date (physical life) for LPG
cylinders?
Expired Cylinders are not safe for use and may cause accidents. In
this regard please be cautious at the time of accepting any LPG
cylinder from the vendor.
Here is how we can check the expiry of LPG cylinders:
On one of three side stems of the cylinder, the expiry date is coded
alpha-numerically as follows A or B or C or D and some two digit
number following this e.g. D06.
The alphabets stand for quarters -
A for March (First Qtr),
B for June (Second Qtr),
C for Sept (Third Qtr), &
D for December (FourthQtr).
The digits stand for the year till it is valid.
Hence D06 would mean December qtr of 2006.
Please ask ur frenz to visit the blog and share this message with everyone you know, UR kind cooperation will save life of many people and create awareness among the public.
Regards,
DJ