WebRTC là gì ?

WebRTC là gì ?

Hãy tưởng tượng một ngày mà điện thoại, máy tính, tivi, có thể kết nối trực tiếp với nhau và thực hiện được các cuộc gọi thông qua một nền tảng chung. Việc giao tiếp của chúng ta sẽ dễ hàng hơn và điều này có thể thay thế các phương phức liên lạc hiện có. Đó là mục tiêu của dự án WebRTC mà Google đang theo đuổi, WebRTC được kỳ vọng sẽ tạo bước ngoặt lớn trong cách mà chúng ta giao tiếp.

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Build an API in your Rails app now!

Build an API in your Rails app now!

Over the past months we have been building various APIs here in Kollegorna using Rails. Although there has been a lot of fuzz about API frameworks in Ruby community like the sinatra-way and Grape the truth is that I never felt that Rails limits you when building APIs, especially if you have a large one. Continue reading “Build an API in your Rails app now!”

Decorator – cầu nối giữa View và Model

Decorator – cầu nối giữa View và Model

Như chúng ta đã biết, Rails được xây dựng trên mô hình MVC, với Controller là cầu nối xử lý dữ liệu giữa View và Model. Ngoài 3 lớp này, Rails còn có thêm helper. Helper thường được coi là nơi chứa các đoạn mã logic phức tạp thay cho View.

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How to create a self-signed SSL Certificate

How to create a self-signed SSL Certificate

Overview

The following is an extremely simplified view of how SSL is implemented and what part the certificate plays in the entire process.

Normal web traffic is sent unencrypted over the Internet. That is, anyone with access to the right tools can snoop all of that traffic. Obviously, this can lead to problems, especially where security and privacy is necessary, such as in credit card data and bank transactions. The Secure Socket Layer is used to encrypt the data stream between the web server and the web client (the browser).

SSL makes use of what is known as asymmetric cryptography, commonly referred to as public key cryptography (PKI). With public key cryptography, two keys are created, one public, one private. Anything encrypted with either key can only be decrypted with its corresponding key. Thus if a message or data stream were encrypted with the server’s private key, it can be decrypted only using its corresponding public key, ensuring that the data only could have come from the server.

If SSL utilizes public key cryptography to encrypt the data stream traveling over the Internet, why is a certificate necessary? The technical answer to that question is that a certificate is not really necessarythe data is secure and cannot easily be decrypted by a third party. However, certificates do serve a crucial role in the communication process. The certificate, signed by a trusted Certificate Authority (CA), ensures that the certificate holder is really who he claims to be. Without a trusted signed certificate, your data may be encrypted, however, the party you are communicating with may not be whom you think. Without certificates, impersonation attacks would be much more common.

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