HTTPS

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Hypertext Transfer Protocol Secure (HTTPS) is a combination of the Hypertext Transfer Protocol with the SSL/TLS protocol to provide encryption and secure (website security testing) identification of the server. HTTPS connections are often used for payment transactions on the World Wide Web and for sensitive transactions in corporate information systems. HTTPS should not be confused with Secure HTTP (S-HTTP) specified in RFC 2660

The main idea of HTTPS is to create a secure channel over an insecure network. This ensures reasonable protection from eavesdroppers and man-in-the-middle attacks, provided that adequate cipher suites are used and that the server certificate is verified and trusted.

The trust inherent in HTTPS is based on major certificate authorities which come pre-installed in browser software (this is equivalent to saying “I trust certificate authority (e.g. VeriSign/Microsoft/etc.) to tell me who I should trust”). Therefore an HTTPS connection to a website can be trusted if and only if all of the following are true:

1. The user trusts the certificate authority to vouch only for legitimate websites without misleading names.
2. The website provides a valid certificate (an invalid certificate shows a warning in most browsers), which means it was signed by a trusted authority.
3. The certificate correctly identifies the website (e.g. visiting https://example and receiving a certificate for “Example Inc.” and not anything else ).
4. Either the intervening hops on the Internet are trustworthy, or the user trusts the protocol’s encryption layer (TLS or SSL) is unbreakable by an eavesdropper.

Browser integration

When connecting to a site with an invalid certificate, older browsers would present the user with a dialog box asking if they wanted to continue. Newer browsers display a warning across the entire window. Newer browsers also prominently display the site’s security information in the address bar.

Extended validation certificates turn the address bar green in newer browsers. Most browsers also pop up a warning to the user when visiting a site that contains a mixture of encrypted and unencrypted content.
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Multimedia bit rates

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In digital multimedia, bitrate represents the amount of information, or detail, that is stored per unit of time of a recording. The bitrate depends on several factors:

* The original material may be sampled at different frequencies
* The samples may use different numbers of bits
* The data may be encoded by different schemes
* The information may be digitally compressed by different algorithms or to different degrees

Generally, choices are made about the above factors in order to achieve the desired trade-off between minimizing the bitrate and maximizing the quality of the material when it is played.

If lossy data compression is used on audio or visual data, differences from the original signal will be introduced; if the compression is substantial, or lossy data is decompressed and recompressed, this may become noticeable in the form of compression artifacts. Whether these affect the perceived quality, and if so how much, depends on the compression scheme, encoder power, the characteristics of the input data, the listener’s perceptions, the listener’s familiarity with artifacts, and the listening or viewing environment.

The bitrates in this section are approximately the minimum that the average listener in a typical listening or viewing environment, when using the best available compression, would perceive as not significantly worse than the reference standard:

Audio (MP3)

* 32 kbit/s – MW (AM) quality
* 96 kbit/s – FM quality
* 128–160 kbit/s – Standard Bitrate quality; difference can sometimes be obvious (e.g. lack of low frequency quality and high frequency “swashy” effects)[citation needed]
* 192 kbit/s – DAB (Digital Audio Broadcasting) quality.
* 224–320 kbit/s – VBR to highest MP3 quality

Other audio

* 800 bit/s – minimum necessary for recognizable speech (using special-purpose FS-1015 speech codecs)
* 8 kbit/s – telephone quality (using speech codecs)
* 32-500 kbit/s — lossy audio as used in Ogg Vorbis
* 500 kbit/s–1,411kbit/s – lossless audio as used in formats such as Free Lossless Audio Codec, WavPack or Monkey’s Audio
* 1,411.2 kbit/s – PCM sound format of Compact Disc Digital Audio

Video

* 16 kbit/s – videophone quality (minimum necessary for a consumer-acceptable “talking head” picture using various video compression schemes)
* 128 – 384 kbit/s – business-oriented videoconferencing quality using video compression
* 1.25 Mbit/s – VCD quality (with bit-rate reduction from MPEG-1 video compression)[citation needed]
* 1374 kbit/s – VCD (Video CD) – audio and video streams multiplexed in an MPEG-PS
* 3.5 Mbit/s typ – Standard-definition television quality (with bit-rate reduction from MPEG-2 compression)
* 5 Mbit/s typ – DVD quality (with bit-rate reduction from MPEG-2 compression)
* 8 to 15 Mbit/s typ – HDTV quality (with bit-rate reduction from MPEG-4 AVC compression)
* 29.4 Mbit/s max – HD DVD
* 40 Mbit/s max – Blu-ray Disc

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Amazon S3

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Amazon S3 (Simple Storage Service) is an online storage web service offered by Amazon Web Services. Amazon S3 provides unlimited storage through a simple web services interface. Amazon launched S3, its first publicly-available web service, in the United States in March 2006 and in Europe in November 2007. Since its inception, Amazon has charged end users US$0.15 per gigabyte-month, with additional charges for bandwidth used in sending and receiving data, and a per-request (get or put) charge. As of November 1, 2008, pricing moved to tiers where end users storing more than 50 terabytes receive discounted pricing. Amazon claims that S3 uses the same scalable storage infrastructure that Amazon.com uses to run its own global e-commerce network. Amazon S3 is reported to store more than 102 billion objects as of March 2010. This is up from 64 billion as of August 2009, 52 billion objects as of March 2009, 29 billion objects as of October 2008, 14 billion objects as of January 2008, and from 10 billion in October 2007. S3 uses include web hosting, image hosting, and a back-up system. S3 comes with a 99.9% monthly uptime guarantee.
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SPDY

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SPDY, pronounced “Speedy”, is an application-level protocol for transporting web content. It is a proposed replacement for the HTTP protocol and created by Google.

The goal of SPDY is to reduce web page load time.This is achieved by prioritizing and multiplexing the transfer of several files so that only one connection per client is required. All transmissions are SSL encrypted and gzip compressed by design (in contrast to HTTP, the headers are compressed too). Moreover, servers may hint or even push content instead of awaiting individual requests for each resource of a web page.

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Microsoft security essentials

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Microsoft Security Essentials (MSE) (previously codenamed Morro) is a free antivirus software created by Microsoft that provides protection against viruses, spyware, rootkits, and trojans for Windows XP (x86), Windows Vista, and Windows 7 (both x86 and x64), free of charge. MSE replaces Windows Live OneCare, a commercial subscription-based antivirus service and the free Windows Defender, which only protected users from adware and spyware. It is geared for consumer use, unlike Microsoft’s upcoming enterprise-oriented product Microsoft Forefront.

Symantec and McAfee, two competing antivirus vendors, responded by claiming that MSE is not as good as their own software. AVG Technologies viewed MSE positively, stating it reinforced the company’s ideal of free antivirus software. Reviews were mostly positive, citing its organized interface, low resource usage, and its status as freeware.
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