An overview of the

This article is the second chapter of WebSocket protocol. The main content of this article is the introduction of related terms in WebSocket protocol.

2 Consistency Requirements (Chapter 2 Agreement Text)

In this document, all the diagrams, examples, and notes are non-normative, as are all the chapters marked as non-normative. Anything else that is not specified in the document is normative.

Key words in this document are “MUST”, “MUST NOT”, “need”, “SHALL”, “SHALL NOT”, “SHOULD”, “SHOULD NOT” “NOT)”, “RECOMMENDED”, “MAY” and “OPTIONAL” can be explained as described in RFC2119.

Imperative statements that are part of an algorithm (such as “delete any leading whitespaces” or “return false and abort subsequent steps”) SHOULD be explained along with keywords (” MUST, “” SHOULD,” “MAY,” etc.) when introducing the algorithm.

The desired wording of an algorithm or specified step can be expressed in any way, as long as the end result is equivalent. (Especially in algorithm definitions, we aim for the simplest possible operation rather than the most perfect.)

2.1 Terminology and other conventions

_ASCII_ represents the character encoding table defined in ANSI.x3-4.1986.

This document references UTF-8 values, using the UTF-8 standard format defined in STD 63 (RFX3629).

Such as naming algorithms or identifiers defining key inputs such as _this_.

Named after the header fields or variables such as | this |.

This article references the WebSocket connection failure (_Fail the WebSocket Connection_) program. This program is located in section 7.1.7.

Converting a lower-case character (_Converting a string to ASCII lowercase_) means replacing all the characters from U+0041 to U+005A (Latin capital A to Z) with the corresponding characters from U+0061 to U+007A (Latin lowercase A-z).

ASCII case-insensitive (_ASCII Case-InSensitive_) comparison means comparing these two characters by code point, If the characters are U+0041 to U+005A (Latin capitals A to Z) and the corresponding characters U+0061 to U+007A (Latin lowercase A-z), then the two characters are also considered equal.

The word URI is defined in RFC3986.

When the _send_ data part of the WebSocket protocol needs to be implemented, it is possible for the implementation to delay the data transfer for any length of time, for example, using a data buffer to ensure that fewer IP packets are sent.

This document uses both the extended bacos-nohr normal form (ABNF) in RFC5234 and RFC2616 in different sections.