Firefox 35 was released this week and became the first browser to enable support for the HTTP/2 protocol by default.
The HTTP/2 specification has not been finalised so Firefox actually enabled the Draft 14 version of HTTP/2 but little is expected to change in the final draft. Google is now supporting HTTP/2 draft 14 on its web servers alongside the SPDY protocol giving us a chance to compare the performance of raw HTTPS, SPDY and HTTP/2 on the same web page.
We also updated HttpWatch this week so that it supports HTTP/2 within Firefox. It has new columns to display information about the protocols being used by each request:
The Performance Comparison
The performance test used HttpWatch with Firefox to run a series of simple page load tests against the Google UK home page using the three protocols:
Raw HTTPS
SPDY/3.1
HTTP/2
We switched between the protocols by enabling and disabling the following entries in Firefox’s about:config page:
Each test was performed in a fresh instance of Firefox with an empty browser cache. Although this testing was simplistic and only used a simple page it does highlight some important differences between the protocols. Continue reading »
Edward Snowden公开的NSA机密文件显示,即使用户强加密了邮件内容,邮件的重要元数据仍旧是未加密的明文。元数据含有重要信息:发信者和收信者的地址、邮件主题行、邮件头,邮件转发服务器信息。
Lavabit的创始人Ladar Levison和PGP 作者 Phil Zimmermann 因此在2013年发起了Dark Mail项目,试图开发新协议解决这些问题。
Dark Mail项目去年底发布了替代现有邮件系统的Dark Internet Mail Environment (DIME)规格(PDF)。DIME系统包括了新的电子邮件消息格式和电子邮件交换和身份认证协议,它同时还努力保持了与现有系统的向后兼容性。DIME描绘了一种消息格式,其信息的每一个部分都分开加密,不同部分使用不同的密钥。因此邮件传输代理只能解密传输信息所需要的部分,而邮件发送代理能在不知道发信者和信息内容的情况下将邮件发送到正确用户的收件箱。 它是如何做到的?
一个DIME消息对象包含了三个部分:Next-Hop(目前邮件传输方法使用的未加密路由信息)、Envelope(分开加密的发信方和收信方信息)和Content(分开加密的消息头和消息体)。
Phillip Zimmermann 和Ladar Levison 等人宣布了替代SMTP协议的Darkmail Internet Mail Environment。目前电子邮件服务使用的SMTP协议被认为不安全,会泄露重要的发件人收件人元数据。一个安全的电子邮件协议必须限制元数据信息泄露,而邮件处理代理仅能访问它们需要看到的信息。Dark Internet Mail Environment(DIME) 通过有多层密钥管理和多层信息加密的核心模式实现这一目标。DIME的规格已经公布,代码发布在GitHub上。