What is base64 encoding used for?

Question

I've heard people talking about "base 64 encoding" here and there. What is it used for?

Answer 1

“Base64 encoding schemes are commonly used when there is a need to encode binary data that needs be stored and transferred over media that are designed to deal with textual data. This is to ensure that the data remains intact without modification during transport”(Wiki, 2017)

Example could be the following: you have a web service that accept only ASCII chars. You want to save and then transfer user’s data to some other location (API) but recipient want receive untouched data. Base64 is for that. . . The only downside is that base64 encoding will require around 33% more space than regular strings.

Another Example:: uenc = url encoded = aHR0cDovL2xvYy5tYWdlbnRvLmNvbS9hc2ljcy1tZW4tcy1nZWwta2F5YW5vLXhpaS5odG1s = http://loc.querytip.com/asics-men-s-gel-kayano-xii.html.

As you can see we can’t put char “/” in URL if we want to send last visited URL as parameter because we would break attribute/value rule for “MOD rewrite” – GET parameter.

A full example would be: “http://loc.querytip.com/checkout/cart/add/uenc/http://loc.magento.com/asics-men-s-gel-kayano-xii.html/product/93/”

Answer 2

When you have some binary data that you want to ship across a network, you generally don't do it by just streaming the bits and bytes over the wire in a raw format. Why? because some media are made for streaming text. You never know -- some protocols may interpret your binary data as control characters (like a modem), or your binary data could be screwed up because the underlying protocol might think that you've entered a special character combination (like how FTP translates line endings).

So to get around this, people encode the binary data into characters. Base64 is one of these types of encodings.

Why 64?
Because you can generally rely on the same 64 characters being present in many character sets, and you can be reasonably confident that your data's going to end up on the other side of the wire uncorrupted.

Answer 3

From http://en.wikipedia.org/wiki/Base64

The term Base64 refers to a specific MIME content transfer encoding. It is also used as a generic term for any similar encoding scheme that encodes binary data by treating it numerically and translating it into a base 64 representation. The particular choice of base is due to the history of character set encoding: one can choose a set of 64 characters that is both part of the subset common to most encodings, and also printable. This combination leaves the data unlikely to be modified in transit through systems, such as email, which were traditionally not 8-bit clean.

Base64 can be used in a variety of contexts:

• Evolution and Thunderbird use Base64 to obfuscate e-mail passwords[1]
• Base64 can be used to transmit and store text that might otherwise cause delimiter collision

• Base64 is often used as a quick but insecure shortcut to obscure secrets without incurring the overhead of cryptographic key management

• Spammers use Base64 to evade basic anti-spamming tools, which often do not decode Base64 and therefore cannot detect keywords in encoded messages.

• Base64 is used to encode character strings in LDIF files
• Base64 is sometimes used to embed binary data in an XML file, using a syntax similar to ...... e.g. Firefox's bookmarks.html.
• Base64 is also used when communicating with government Fiscal Signature printing devices (usually, over serial or parallel ports) to minimize the delay when transferring receipt characters for signing.
• Base64 is used to encode binary files such as images within scripts, to avoid depending on external files.
• Can be used to embed raw image data into a CSS property such as background-image.

Answer 4

Mostly, I've seen it used to encode binary data in contexts that can only handle ascii - or a simple - character sets.

Answer 5

Base64 can be used for many purposes.

The primary reason is to convert binary data to something passable.

I sometimes use it to pass JSON data around from one site to another, store information in cookies about a user.

Note: You "can" use it for encryption - I don't see why people say you can't, and that it's not encryption, although it would be easily breakable and is frowned upon. Encryption means nothing more than converting one string of data to another string of data that can be either later decrypted or not, and that's what base64 does.

Answer 6

Base-64 encoding is a way of taking binary data and turning it into text so that it's more easily transmitted in things like e-mail and HTML form data.

http://en.wikipedia.org/wiki/Base64