Archive for December, 2015

Let’s Encrypt has opened to the public, allowing anyone to obtain Free SSL/TLS (Secure Socket Layer/Transport Layer Security) certificates for their web servers and to set up HTTPS websites in a few simple steps (mentioned below).
Let’s Encrypt – an initiative run by the Internet Security Research Group (ISRG) – is a new, free, and open certificate authority recognized by all major browsers, including Google’s Chrome, Mozilla’s Firefox and Microsoft’s Internet Explorer.
The Free SSL Certification Authority is now in public beta after testing a trial among a select group of volunteers.

Why Let’s Encrypt?

Let’s Encrypt promised to offer a certificate authority (CA) which is:
  • Free – no charge for HTTPS certs.
  • Automatic – the installation, configuration as well as the renewal of the certificates do not require any administrator action.
  • Open – the automatic issuance, as well as renewal procedures, will be published as the open standard.
  • Transparent – the records of all certs issuance or revocation will be available publicly.
  • Secure – the team is committed to being a model of best practice in their own operations.
  • Cooperative – Let’s Encrypt is managed by a multi-stakeholder organization and exists to benefit the community, not any of the consortium members.

How to Install Let’s Encrypt Free SSL Certificate

First of all, let’s say you want to get a certificate for To run the installation, you must have root access to your web server.
To Generate and Install Let’s Encrypt Free SSL Certificate, you must first download and run the Let’s Encrypt client application.

To install Let’s Encrypt Free SSL certificate follow these Steps:
Step 1: Login to your ‘’ web server using SSH with root access.

Step 2: To install the Git version control system, type the following command:

apt-get install git

Step 3: Then download and install the latest version of Let’s Encrypt Client application, type the following commands:

git clone
cd letsencrypt

Step 4: Once the installation starts, press Enter to accept the agreement.

Step 5: Then press Enter to specify the server name manually in the text box (for example, and then press Enter.

Step 6: Next, enter your email address, where you can receive messages from Let’s Encrypt and to recover lost keys, and then press Enter.

Step 7: Review the ‘Terms of Service,’ and then press Enter to generate and install the SSL certificate.
Once the installation completes, you’ll receive a ‘Congratulation‘ message.

How to Configure Nginx/Apache for Let’s Encrypt SSL Certificate

By default, Nginx or Apache web servers are not configured to how to use your new certificates.
For example, in case of Nginx: To use the installed SSL certificate, you need to edit Nginx configuration file. Type the following command to open Nginx configuration file:

$ sudo nano /etc/nginx/sites-available/

Within that file, add the following lines.


listen 443 ssl;
ssl_certificate /etc/letsencrypt/live/;
ssl_certificate_key /etc/letsencrypt/live/;


Save the file, and just restart your Nginx web server, using the following command:

sudo nginx -s reload

That’s it! Check complete documentation here.

Congratulation you have successfully installed SSL certificate for your domain.
How to Renew Let’s Encrypt Free SSL Certificate: It is important to note that the beta version of Let’s Encrypt issues certificates that expire after 90 days. So, to renew your SSL certificate, you need to run theletsencrypt-auto script again after expiration.

FREE HTTPS Certificates for Everyone!

So, now it’s time for the Internet to take a significant step forward in terms of security and privacy. With Let’s Encrypt, the team wants HTTPS becomes the default and to make that possible for everyone, it had built Let’s Encrypt in such a way that it is easy to obtain and manage.

“There’s a reward going for anyone who can find a security hole in the service,” the team wrote in ablog post. “We have more work to do before we’re comfortable dropping the beta label entirely, particularly on the client experience.”

“Automation is a cornerstone of our strategy, and we need to make sure that the client works smoothly and reliably on a wide range of platforms. We’ll be monitoring feedback from users closely, and making improvements as quickly as possible.”

Let’s Encrypt had signed its first free HTTPS certificate in September, and its client software emerged in early November. Since then the team has been finding flaws in their systems before going public.

Bitcoin can be confusing for new comers. Luckily, we’ve got it covered for you.

I just bought my first bitcoin. Here’s what I learned

When it comes to Bitcoin, I’ve always been an outsider looking in. Living in China, government crackdowns have made the cryptocurrency largely inaccessible, so I’ve been content to sit on the sidelines and observe.

Eventually, however, my curiosity got the best of me, and I decided to take the plunge. I am a Bitcoin believer, and I want to walk the talk. After some thorough research, I bought US$100 worth. So, in the interest of spreading the word, here’s some first-hand advice for first-time bitcoin buyers.

Where to buy bitcoins – choose the right exchange

The first question I had was – “where to buy bitcoins from?” With dozens upon dozens of exchanges in the world, I chose US-based Coinbase. Originally, I wanted to try out one of the many exchanges in Asia that I’ve written about in the past, but ultimately went with Coinbase because it’s in the same country as my primary bank account. I highly recommend you filter your search by finding exchanges in your home country or ones that explicitly state they accept transfers from your bank, otherwise you will risk unnecessary bureaucracy headaches and transfer fees. I also wouldn’t suggest buying from individuals on your first attempt. Here’s a brief (and by no means exhaustive) list of exchanges in Asian countries:

So what should you be looking for? The number one priority should be security. This is real currency we’re talking about (despite what some governments might think), but rules and regulations are not yet up to the same standard as real banks and other financial institutions. If an exchange goes down, all of its customers’ assets can go down with it (see: Mt. Gox).

Do some background research on each of the available exchanges in your country. Have they been around awhile? Do they have good reviews? Are there any news articles about them getting hacked? Are the founders some fresh IT grads or experienced financial professionals?

Make sure the exchange uses two-factor authentication – a security measure used when logging into your account from a new device that requires two methods to prove your identity. Sometimes this is an email address and a phone number, while some exchanges require an actual scan of photo ID.

Cold storage is another plus. Not all exchanges have this, but I prefer those that do. Cold storage is sort of like the opposite of cloud storage – disconnected from the internet and kept completely out of the reach of hackers, and other forms of catastrophe.

Next, look for the features you want in an exchange. Remittances will require cooperation with local banks in the destination country. If you don’t have a bank account, look for exchanges with nearby bitcoin ATMs or a voucher system. Margin trading, instant withdrawals, automatic trading, and the option to buy altcoins (Litecoin, Dogecoin, etc) are all worth considering depending on your needs.

See: Beginner’s guide to buying and storing Litecoin
Transaction fees are also important to keep in mind and vary from exchange to exchange, but competition has driven most of them down to keep their prices low.

Apart from it being in my home country, I chose Coinbase because it uses two-factor authentication and cold storage, has a clean reputation, and offers instant buying up to US$100.

Choose the right wallet

Finding a wallet, an app from which you can send and receive bitcoin, is the next step. A search on any major app store returns tons of options, but using one made by the exchange which you buy from will make your life easier. Coinbase has both a mobile wallet app and a browser wallet on its website that sync with each other.

It’s convenient that I don’t have to transfer the bitcoins to a separate wallet, and I don’t have to worry about losing my bitcoins if I lose my phone or my computer dies. That’s a double-edged sword, though, because if Coinbase gets hacked or goes dark for some other reason, my bitcoins will go with it.

Bitcoin Wallet - Android Apps on Google Play

Not all exchanges have wallets, which really only leaves you with the option of using a third-party wallet. If you go this route, extra steps are needed to make sure it’s secure. You’ll have to back up your wallet and sync it regularly to multiple secure locations, like password-protected USB drives. It also requires some bandwidth to sync the blockchain. A third-party wallet is much less likely to be targeted by hackers, but is probably not as secure as an exchange’s servers. The decision ultimately comes down to trust and ease of use.

Coinbase’s wallet is very simple and intuitive, which is all I want. I’m not a very active trader, but more serious users might want something more complex. Quoine’s wallet, for instance, has two interfaces for novice and expert users.

How to buy bitcoins

Now time for the actual purpose: buying bitcoin. Most exchanges work in a similar manner, so I’ll use screenshots from Coinbase as a guide. Buying bitcoin is easy, but it’s by no means instant, even with the “instant” option that I used.

First off, you’ll have to connect your bank account. On Coinbase, this is very similar to setting up an account on PayPal, where two small deposits are made to verify that the account number and owner are legitimate. This can take up to four business days alone, but it’s a one-off step. To use the instant purchase feature, I also bound my credit card to my account.

My Wallet - Coinbase

Once your accounts are in order, it’s time to make the purchase. The primary method is to use a bank transfer, and very few exchanges or other services allow you to use a credit card. Coinbase only allows it as a secondary measure, and the instant buy amount is capped at US$100.

You can input the amount in either bitcoin or your preferred fiat currency (yen, kroner, euro, etc.), but make sure to check the price as bitcoin rates tend to fluctuate rather violently. My US$100 worth of bitcoin was worth just US$90 one day later.

Buy Bitcoin - Coinbase

Once the purchase is submitted, the transaction will be pending for at least two more days. This is because bank transfers take time and because the bitcoin network needs to validate the transaction and add it to the blockchain – a shared database used by everyone on the bitcoin protocol that records every transaction ever made using bitcoin.

My Wallet - Coinbase (1)

You won’t be able to spend, send, or sell these bitcoins until the transaction is verified by the blockchain. Depending on the exchange, this varies by the number of times the transaction is verified by peers on the network – it needs to be double, triple, and even sextuple checked to ensure everything is in order.

Buy Bitcoin - Coinbase (1)

See: Pick up your pickaxes and headlamps: here’s how Bitcoin mining works

Sending and receiving bitcoins

Now that you’ve got some bitcoin in your wallet, sending and receiving it is easy. In my example, I’m going to send a very small amount of bitcoin from the third-party wallet installed on my PC, MultiBit, to my Coinbase wallet.

First, you’ll need your wallet’s address. Just look around the menus and you’re sure to find it. You can either copy and paste the address – usually a long string of random characters – manually, or use the QR code scanner built into your phone’s wallet app. NFC is also an option for physical payments.

bitcoin address

Next, type in a label indicating what the transaction is for and the amount you want to send. Double check to make sure you have enough to cover any transfer fees, which is usually a very small amount. Then hit send.

multibit ss

Voila! You’ve now sent (or received) some bitcoin. Just like buying from the exchange, it will take some time for the transaction to take effect in the blockchain.

If you want someone to send you bitcoin, you can use your wallet’s request function, or just give the sender your wallet address. Even though the address looks like a complicated password, it doesn’t have to be secret. Many organizations display it publicly to collect donations or other forms of payment.

Yes, you can share games with others, on one or more consoles

One of the more confusing and even controversial aspects to Xbox One is its ability to let users share their games with others, on the same console and between consoles. But how does this work? And how does this feature impact a family with multiple users and even multiple consoles?

Note: This article refers to electronically purchased games, not disc-based games unless otherwise noted.

One Xbox One, multiple users

The most common game sharing scenario is a single Xbox One console with multiple users. In this situation, any user can purchase a game electronically through the console, download and install it to the console, and any other user can sign in and play that game, earning achievements, participating in leaderboards, and so on. This works much as you’d expect, and if you think about how an Xbox 360 would work with multiple users and a single copy of a disc-based game, you can see that it’s consistent.

To be fair, Microsoft could very easily have tied an electronic game purchase to a single Microsoft account (aka Xbox Live Gamertag) and then required you to pay for a second copy of the game (perhaps at a reduced price) for an additional user. I suspect the uproar would have been deafening but it’s worth considering.

I assume disc-based games work with the Xbox One in much the same way but have not yet tested this. I will (unhappily). But with a single console, you should be able to share games in the same way regardless of the media type.

Actually, before moving on to the multi-console household, let’s discuss one more thing, and it’s actually pretty magical. If you’re sitting there playing a game, enjoying some entertainment experience, or doing whatever on the Xbox One and a second person walks in the room, one who has previously signed into the console with their own Microsoft account, that person will be signed in automatically and immediately. This feature is nicely demonstrated in this promotional video and it does work exactly as described.

>> Xbox One: His and Hers

Two users, two consoles

So a single console with multiple users is pretty straightforward. But with multiple consoles, things get a bit more hairy.

For starters, you need to deal with an Xbox One feature called “home Xbox,” where each user that is signed in to an Xbox One must have one console that is configured as their home Xbox. (If you only have one Xbox One, then that will be the home Xbox for all configured users.) When you configure a console as your home Xbox, any user that signs in to that Xbox One can play any of your downloaded games without having to first sign in as you.

Read that one again, because it’s important: When you configure a console as your home Xbox, any user that signs in to that Xbox One can play any of your downloaded games without having to first sign in as you.

That means that the converse is also true: On a non-home Xbox One, users will need to sign-in as you before they can play any of your downloaded games.

If this isn’t your home Xbox, others will need to sign in as you to play your games

So here’s the trick, assuming you have two Xbox Ones: Configure the Xbox One you don’t usually use as your home Xbox. The other player will be able to play your games automatically and you will be able to play their games automatically, each on your own console.

It’s that simple.

To make it work, user one signs in to console two with their Microsoft account/Gamertag credentials and configures that console as their home Xbox in Settings, My Home Xbox. User two, meanwhile, will sign in to console one with their Microsoft account/Gamertag and configure that console as their home Xbox.

The Your Home Xbox interface

Once this has happened, any user on either of the consoles can download and install the other user’s games. They appear at the end of the Games & Apps list with little cloud icons on their tiles.

My son’s games appearing at the end of my Games & Apps list

And when you run the other person’s game titles, they work just fine. All you have to do is configure that home Xbox feature correctly.

In real world terms, this is quite interesting. In my home, we have two Xbox One consoles: My console, in my home office, and my son’s, which is in the basement. My Xbox One is configured as my son’s home Xbox, and my son’s Xbox One is configured as my home Xbox. We both have access to each other’s downloadable game library and can play each other’s games, even at the same time, while signed in under our own Microsoft account/Gamertag credentials. We should never need to buy two copies of a (digital) game again, if I’m understanding this correctly.

That is pretty amazing. But it does raise questions about how this might work if we were to add another Xbox One to the mix. After all, we’re going to want one of these things in the living room too.