rfc2237.Japanese Character Encoding for Internet Messages

合集下载

imap rfc标准

Internet Message Access Protocol (IMAP) is an email retrieval protocol. It stores email messages on a mail server and enables the recipient to view and manipulate them as though they were stored locally on their device. IMAP was developed in the late 1980s and has since become one of the most widely used email retrieval protocols.The IMAP standard is defined in RFC 3501, which was published in 2003. This document provides a detailed description of the protocol's functionality, including its data formats, commands, and responses. The standard specifies how IMAP clients and servers should communicate with each other to enable the retrieval and manipulation of email messages.One of the key features of IMAP is its support for multiple clients accessing the same mailbox simultaneously. This is achieved through the use of a "shared" storage model, where all clients see the same set of messages and folders stored on the server. This allows users to access their email from different devices without having to worry about synchronizing their messages manually.Another important aspect of IMAP is its support for message organization and management. Clients can create, delete, and rename folders, as well as move messages between folders. They can also search for specific messages based on various criteria, such as sender, subject, or date.IMAP also provides a range of features for managing individual messages. Clients can mark messages as read or unread, flag them for follow-up, and even move them to a specific folder. They can also reply to messages, forward them to others, and generate replies or forwards with attachments.Overall, the IMAP standard provides a powerful and flexible framework for managing email messages. Its support for shared storage, message organization, and advanced message management features make it a popular choice for both personal and business email users.。

Extreme Networks SLX 9640高性能固定路由器商品介绍说明书

ExtremeRouting? SLX 9640
Built to Suit Your Business Needs Ext rem e Elem ent s are t he b uild ing b locks t hat allow you t o t ailor your net w ork t o your sp ecific b usiness environm ent , g oals, and ob ject ives. They enab le t he creat ion of an A ut onom ous Net w ork t hat d elivers t he p osit ive exp eriences and b usiness out com es m ost im p ort ant t o your org anizat ion.
W W W.EXTREMENETW
1
Flexib le Bo rd er Ro ut ing w it h Int ernet Scale, Ult ra-Deep Buffers,
MPLS and EVPN
The SLX 964 0 is a very p ow erful com p act d eep b uffer Int ernet b ord er rout er, p rovid ing a cost -efficient solut ion t hat is p urp ose-b uilt for t he m ost d em and ing service p rovid er and ent erp rise d at a cent ers and MA N/ WA N ap p licat ions. The rob ust syst em archit ect ure sup p ort ed by SLX-OS and a versat ile feat ure set includ ing IPv4 , IPv6, and MPLS/ VPLS w it h Carrier Et hernet 2.0 and OA M cap ab ilit ies t o p rovid e d ep loym ent flexib ilit y.

rfc3232.Assigned Numbers RFC 1700 is Replaced by an On-line Database

Network Working Group J. Reynolds, Editor Request for Comments: 3232 RFC Editor Obsoletes: 1700 January 2002 Category: InformationalAssigned Numbers: RFC 1700 is Replaced by an On-line DatabaseStatus of this MemoThis memo provides information for the Internet community. It doesnot specify an Internet standard of any kind. Distribution of thismemo is unlimited.Copyright NoticeCopyright (C) The Internet Society (2002). All Rights Reserved. AbstractThis memo obsoletes RFC 1700 (STD 2) "Assigned Numbers", whichcontained an October 1994 snapshot of assigned Internet protocolparameters.DescriptionFrom November 1977 through October 1994, the Internet AssignedNumbers Authority (IANA) periodically published tables of theInternet protocol parameter assignments in RFCs entitled, "AssignedNumbers". The most current of these Assigned Numbers RFCs hadStandard status and carried the designation: STD 2. At this time,the latest STD 2 is RFC 1700.Since 1994, this sequence of RFCs have been replaced by an onlinedatabase accessible through a web page (currently, ).The purpose of the present RFC is to note this fact and to officially obsolete RFC 1700, whose status changes to Historic. RFC 1700 isobsolete, and its values are incomplete and in some cases may bewrong.We expect this series to be revived in the future by the new IANAorganization.Security ConsiderationsThis memo does not affect the technical security of the Internet. Reynolds Informational [Page 1]Author’s AddressJoyce K. ReynoldsRFC Editor4676 Admiralty WayMarina del Rey, CA 90292USAEMail: rfc-editor@Reynolds Informational [Page 2]Full Copyright StatementCopyright (C) The Internet Society (2002). All Rights Reserved.This document and translations of it may be copied and furnished toothers, and derivative works that comment on or otherwise explain it or assist in its implementation may be prepared, copied, publishedand distributed, in whole or in part, without restriction of anykind, provided that the above copyright notice and this paragraph are included on all such copies and derivative works. However, thisdocument itself may not be modified in any way, such as by removingthe copyright notice or references to the Internet Society or otherInternet organizations, except as needed for the purpose ofdeveloping Internet standards in which case the procedures forcopyrights defined in the Internet Standards process must befollowed, or as required to translate it into languages other thanEnglish.The limited permissions granted above are perpetual and will not berevoked by the Internet Society or its successors or assigns.This document and the information contained herein is provided on an "AS IS" basis and THE INTERNET SOCIETY AND THE INTERNET ENGINEERINGTASK FORCE DISCLAIMS ALL WARRANTIES, EXPRESS OR IMPLIED, INCLUDINGBUT NOT LIMITED TO ANY WARRANTY THAT THE USE OF THE INFORMATIONHEREIN WILL NOT INFRINGE ANY RIGHTS OR ANY IMPLIED WARRANTIES OFMERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE.AcknowledgementFunding for the RFC Editor function is currently provided by theInternet Society.Reynolds Informational [Page 3]。

CHARACTER SETS 字符集

Alias: us
Alias: IBM367
Alias: cp367
Alias: csASCII
Name: ISO_8859-1:1987 [RFC1345,KXS2]
MIBenum: 4
Source: ECMA registry
ISOnnn followed by letters suggestive of the name or standards number
of the code set. When a national or international standard is
revised, the year of revision is added to the cs alias of the new
1000-1999 Unicode / 10646
2000-2999 Vendor
The aliases that start with "cs" have been added for use with the
IANA-CHARSET-MIB as originally defined in RFC3808, and as currently
between use of upper and lower case letters.
The MIBenum value is a unique value for use in MIBs to identify coded
character sets.
The value space for MIBenum values has been divided into three
CHARACTER SETS

RFC2373

组织：中国互动出版网（/）RFC文档中文翻译计划(/compters/emook/aboutemook.htm)E-mail：ouyang@译者：党红梅（snowlily danghongmei@）译文发布时间：2001－4－27版权：本中文翻译文档版权归中国互动出版网所有。

可以用于非商业用途自由转载，但必须保留本文档的翻译及版权信息。

Network Working Group R. Hinden Request for Comments: 2373 Nokia Obsoletes: 1884 S. Deering Category: Standards Track Cisco Systems July 1998IPv6寻址体系结构（RFC2373: IP Version 6 Addressing Architecture）本备忘录的状态本文档讲述了一种Internet社区的Internet标准跟踪协议，它需要进一步进行讨论和建议以得到改进。

请参考最新版的“Internet正式协议标准”(STD1)来获得本协议的标准化程度和状态。

本备忘录的发布不受任何限制。

本文件包括I P v 6 寻址模型、I P v 6 地址的文字表示、I P v 6 单播地址、任意点播地址和组播地址的定义以及I P v 6 节点需要的地址。

目录摘要 11．简介 22. IPv6 寻址 22.1 寻址模型 32.2 地址的文本表示 32.3 地址前缀的文本表示 42.4 地址类型表示 52.5 单播地址 52.5.1 接口标识符 62.5.2 未指定地址72.5.3 回返地址72.5.4 嵌有IPv4 地址的IPv6 地址72.5.5 NSAP 地址72.5.6 IPX 地址82.5.7 可集聚全球单播地址82.5.8 本地用IPv6 单播地址82.6 任意点播地址92．6．1要求的任意点播地址92.7 组播地址102.7.1 预定义的组播地址112.7.2 新IPv6 组播地址的分配122.8 节点要求的地址123. 安全性考虑13附录A 创建EUI-64 接口标识符13A.1 具有EUI-64 标识符的链路或节点13A.2 具有IEEE 802 48 位MAC 地址的链路或节点13A.3 具有非全球标识符的链路14A.4 无标识符的链路14附录B 文本表示的ABNF 描述 15附录C 对RFC 1884 的修改15参考资料16作者联系方法17版权说明171．简介本技术规范定义了I P v 6 的寻址体系结构。

rfc5987.Character Set and Language Encoding for HTTP Header Field Parameters

Internet Engineering Task Force (IETF) J. Reschke Request for Comments: 5987 greenbytes Category: Standards Track August 2010 ISSN: 2070-1721Character Set and Language Encoding forHypertext Transfer Protocol (HTTP) Header Field Parameters AbstractBy default, message header field parameters in Hypertext TransferProtocol (HTTP) messages cannot carry characters outside the ISO-8859-1 character set. RFC 2231 defines an encoding mechanism for use in Multipurpose Internet Mail Extensions (MIME) headers. Thisdocument specifies an encoding suitable for use in HTTP header fields that is compatible with a profile of the encoding defined in RFC2231.Status of This MemoThis is an Internet Standards Track document.This document is a product of the Internet Engineering Task Force(IETF). It represents the consensus of the IETF community. It hasreceived public review and has been approved for publication by theInternet Engineering Steering Group (IESG). Further information onInternet Standards is available in Section 2 of RFC 5741.Information about the current status of this document, any errata,and how to provide feedback on it may be obtained at/info/rfc5987.Copyright NoticeCopyright (c) 2010 IETF Trust and the persons identified as thedocument authors. All rights reserved.This document is subject to BCP 78 and the IETF Trust’s LegalProvisions Relating to IETF Documents(/license-info) in effect on the date ofpublication of this document. Please review these documentscarefully, as they describe your rights and restrictions with respect to this document. Code Components extracted from this document must include Simplified BSD License text as described in Section 4.e ofthe Trust Legal Provisions and are provided without warranty asdescribed in the Simplified BSD License.Reschke Standards Track [Page 1]Table of Contents1. Introduction (2)2. Notational Conventions (2)3. Comparison to RFC 2231 and Definition of the Encoding (3)3.1. Parameter Continuations (3)3.2. Parameter Value Character Set and Language Information (3)3.2.1. Definition (3)3.2.2. Examples (6)3.3. Language Specification in Encoded Words (6)4. Guidelines for Usage in HTTP Header Field Definitions (7)4.1. When to Use the Extension (7)4.2. Error Handling (7)5. Security Considerations (8)6. Acknowledgements (8)7. References (8)7.1. Normative References (8)7.2. Informative References (9)1. IntroductionBy default, message header field parameters in HTTP ([RFC2616])messages cannot carry characters outside the ISO-8859-1 character set ([ISO-8859-1]). RFC 2231 ([RFC2231]) defines an encoding mechanismfor use in MIME headers. This document specifies an encodingsuitable for use in HTTP header fields that is compatible with aprofile of the encoding defined in RFC 2231.Note: in the remainder of this document, RFC 2231 is onlyreferenced for the purpose of explaining the choice of featuresthat were adopted; they are therefore purely informative.Note: this encoding does not apply to message payloads transmitted over HTTP, such as when using the media type "multipart/form-data" ([RFC2388]).2. Notational ConventionsThe key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT","SHOULD", "SHOULD NOT", "RECOMMENDED", "MAY", and "OPTIONAL" in this document are to be interpreted as described in [RFC2119].This specification uses the ABNF (Augmented Backus-Naur Form)notation defined in [RFC5234]. The following core rules are included by reference, as defined in [RFC5234], Appendix B.1: ALPHA (letters), DIGIT (decimal 0-9), HEXDIG (hexadecimal 0-9/A-F/a-f), and LWSP(linear whitespace).Reschke Standards Track [Page 2]Note that this specification uses the term "character set" forconsistency with other IETF specifications such as RFC 2277 (see[RFC2277], Section 3). A more accurate term would be "characterencoding" (a mapping of code points to octet sequences).3. Comparison to RFC 2231 and Definition of the EncodingRFC 2231 defines several extensions to MIME. The sections belowdiscuss if and how they apply to HTTP header fields.In short:o Parameter Continuations aren’t needed (Section 3.1),o Character Set and Language Information are useful, therefore asimple subset is specified (Section 3.2), ando Language Specifications in Encoded Words aren’t needed(Section 3.3).3.1. Parameter ContinuationsSection 3 of [RFC2231] defines a mechanism that deals with the length limitations that apply to MIME headers. These limitations do notapply to HTTP ([RFC2616], Section 19.4.7).Thus, parameter continuations are not part of the encoding defined by this specification.3.2. Parameter Value Character Set and Language InformationSection 4 of [RFC2231] specifies how to embed language informationinto parameter values, and also how to encode non-ASCII characters,dealing with restrictions both in MIME and HTTP header parameters.However, RFC 2231 does not specify a mandatory-to-implement character set, making it hard for senders to decide which character set to use. Thus, recipients implementing this specification MUST support thecharacter sets "ISO-8859-1" [ISO-8859-1] and "UTF-8" [RFC3629].Furthermore, RFC 2231 allows the character set information to be left out. The encoding defined by this specification does not allow that.3.2.1. DefinitionThe syntax for parameters is defined in Section 3.6 of [RFC2616](with RFC 2616 implied LWS translated to RFC 5234 LWSP):Reschke Standards Track [Page 3]parameter = attribute LWSP "=" LWSP valueattribute = tokenvalue = token / quoted-stringquoted-string = <quoted-string, defined in [RFC2616], Section 2.2> token = <token, defined in [RFC2616], Section 2.2>In order to include character set and language information, thisspecification modifies the RFC 2616 grammar to be:parameter = reg-parameter / ext-parameterreg-parameter = parmname LWSP "=" LWSP valueext-parameter = parmname "*" LWSP "=" LWSP ext-valueparmname = 1*attr-charext-value = charset "’" [ language ] "’" value-chars; like RFC 2231’s <extended-initial-value>; (see [RFC2231], Section 7)charset = "UTF-8" / "ISO-8859-1" / mime-charsetmime-charset = 1*mime-charsetcmime-charsetc = ALPHA / DIGIT/ "!" / "#" / "$" / "%" / "&"/ "+" / "-" / "^" / "_" / "‘"/ "{" / "}" / "˜"; as <mime-charset> in Section 2.3 of [RFC2978]; except that the single quote is not included; SHOULD be registered in the IANA charset registrylanguage = <Language-Tag, defined in [RFC5646], Section 2.1>value-chars = *( pct-encoded / attr-char )pct-encoded = "%" HEXDIG HEXDIG; see [RFC3986], Section 2.1attr-char = ALPHA / DIGIT/ "!" / "#" / "$" / "&" / "+" / "-" / "."/ "^" / "_" / "‘" / "|" / "˜"; token except ( "*" / "’" / "%" )Reschke Standards Track [Page 4]Thus, a parameter is either a regular parameter (reg-parameter), aspreviously defined in Section 3.6 of [RFC2616], or an extendedparameter (ext-parameter).Extended parameters are those where the left-hand side of theassignment ends with an asterisk character.The value part of an extended parameter (ext-value) is a token thatconsists of three parts: the REQUIRED character set name (charset),the OPTIONAL language information (language), and a charactersequence representing the actual value (value-chars), separated bysingle quote characters. Note that both character set names andlanguage tags are restricted to the US-ASCII character set, and arematched case-insensitively (see [RFC2978], Section 2.3 and [RFC5646], Section 2.1.1).Inside the value part, characters not contained in attr-char areencoded into an octet sequence using the specified character set.That octet sequence is then percent-encoded as specified in Section2.1 of [RFC3986].Producers MUST use either the "UTF-8" ([RFC3629]) or the "ISO-8859-1" ([ISO-8859-1]) character set. Extension character sets (mime-charset) are reserved for future use.Note: recipients should be prepared to handle encoding errors,such as malformed or incomplete percent escape sequences, or non- decodable octet sequences, in a robust manner. This specification does not mandate any specific behavior, for instance, thefollowing strategies are all acceptable:* ignoring the parameter,* stripping a non-decodable octet sequence,* substituting a non-decodable octet sequence by a replacementcharacter, such as the Unicode character U+FFFD (ReplacementCharacter).Note: the RFC 2616 token production ([RFC2616], Section 2.2)differs from the production used in RFC 2231 (imported fromSection 5.1 of [RFC2045]) in that curly braces ("{" and "}") areexcluded. Thus, these two characters are excluded from the attr- char production as well.Reschke Standards Track [Page 5]Note: the <mime-charset> ABNF defined here differs from the one in Section 2.3 of [RFC2978] in that it does not allow the singlequote character (see also RFC Errata ID 1912 [Err1912]). Inpractice, no character set names using that character have beenregistered at the time of this writing.3.2.2. ExamplesNon-extended notation, using "token":foo: bar; title=EconomyNon-extended notation, using "quoted-string":foo: bar; title="US-$ rates"Extended notation, using the Unicode character U+00A3 (POUND SIGN):foo: bar; title*=iso-8859-1’en’%A3%20ratesNote: the Unicode pound sign character U+00A3 was encoded into thesingle octet A3 using the ISO-8859-1 character encoding, thenpercent-encoded. Also, note that the space character was encoded as %20, as it is not contained in attr-char.Extended notation, using the Unicode characters U+00A3 (POUND SIGN)and U+20AC (EURO SIGN):foo: bar; title*=UTF-8’’%c2%a3%20and%20%e2%82%ac%20ratesNote: the Unicode pound sign character U+00A3 was encoded into theoctet sequence C2 A3 using the UTF-8 character encoding, thenpercent-encoded. Likewise, the Unicode euro sign character U+20ACwas encoded into the octet sequence E2 82 AC, then percent-encoded.Also note that HEXDIG allows both lowercase and uppercase characters, so recipients must understand both, and that the language information is optional, while the character set is not.3.3. Language Specification in Encoded WordsSection 5 of [RFC2231] extends the encoding defined in [RFC2047] toalso support language specification in encoded words. Although theHTTP/1.1 specification does refer to RFC 2047 ([RFC2616], Section2.2), it’s not clear to which header field exactly it applies, andwhether it is implemented in practice (see</wg/httpbis/trac/ticket/111> for details).Thus, this specification does not include this feature.Reschke Standards Track [Page 6]4. Guidelines for Usage in HTTP Header Field DefinitionsSpecifications of HTTP header fields that use the extensions defined in Section 3.2 ought to clearly state that. A simple way to achieve this is to normatively reference this specification, and to includethe ext-value production into the ABNF for that header field.For instance:foo-header = "foo" LWSP ":" LWSP token ";" LWSP title-paramtitle-param = "title" LWSP "=" LWSP value/ "title*" LWSP "=" LWSP ext-valueext-value = <see RFC 5987, Section 3.2>Note: The Parameter Value Continuation feature defined in Section 3 of [RFC2231] makes it impossible to have multiple instances ofextended parameters with identical parmname components, as theprocessing of continuations would become ambiguous. Thus,specifications using this extension are advised to disallow thiscase for compatibility with RFC 2231.4.1. When to Use the ExtensionSection 4.2 of [RFC2277] requires that protocol elements containinghuman-readable text are able to carry language information. Thus,the ext-value production ought to be always used when the parametervalue is of textual nature and its language is known.Furthermore, the extension ought to also be used whenever theparameter value needs to carry characters not present in the US-ASCII ([USASCII]) character set (note that it would be unacceptable todefine a new parameter that would be restricted to a subset of theUnicode character set).4.2. Error HandlingHeader field specifications need to define whether multiple instances of parameters with identical parmname components are allowed, and how they should be processed. This specification suggests that aparameter using the extended syntax takes precedence. This wouldallow producers to use both formats without breaking recipients that do not understand the extended syntax yet.Example:foo: bar; title="EURO exchange rates";title*=utf-8’’%e2%82%ac%20exchange%20ratesReschke Standards Track [Page 7]In this case, the sender provides an ASCII version of the title forlegacy recipients, but also includes an internationalized version for recipients understanding this specification -- the latter obviouslyought to prefer the new syntax over the old one.Note: at the time of this writing, many implementations failed to ignore the form they do not understand, or prioritize the ASCIIform although the extended syntax was present.5. Security ConsiderationsThe format described in this document makes it possible to transport non-ASCII characters, and thus enables character "spoofing"scenarios, in which a displayed value appears to be something otherthan it is.Furthermore, there are known attack scenarios relating to decodingUTF-8.See Section 10 of [RFC3629] for more information on both topics.In addition, the extension specified in this document makes itpossible to transport multiple language variants for a singleparameter, and such use might allow spoofing attacks, where different language versions of the same parameter are not equivalent. Whether this attack is useful as an attack depends on the parameterspecified.6. AcknowledgementsThanks to Martin Duerst and Frank Ellermann for help figuring outABNF details, to Graham Klyne and Alexey Melnikov for general review, to Chris Newman for pointing out an RFC 2231 incompatibility, and to Benjamin Carlyle and Roar Lauritzsen for implementer’s feedback.7. References7.1. Normative References[ISO-8859-1] International Organization for Standardization,"Information technology -- 8-bit single-byte codedgraphic character sets -- Part 1: Latin alphabet No.1", ISO/IEC 8859-1:1998, 1998.[RFC2119] Bradner, S., "Key words for use in RFCs to IndicateRequirement Levels", BCP 14, RFC 2119, March 1997. Reschke Standards Track [Page 8][RFC2616] Fielding, R., Gettys, J., Mogul, J., Frystyk, H.,Masinter, L., Leach, P., and T. Berners-Lee, "Hypertext Transfer Protocol -- HTTP/1.1", RFC 2616, June 1999.[RFC2978] Freed, N. and J. Postel, "IANA Charset RegistrationProcedures", BCP 19, RFC 2978, October 2000.[RFC3629] Yergeau, F., "UTF-8, a transformation format of ISO10646", RFC 3629, STD 63, November 2003.[RFC3986] Berners-Lee, T., Fielding, R., and L. Masinter,"Uniform Resource Identifier (URI): Generic Syntax",RFC 3986, STD 66, January 2005.[RFC5234] Crocker, D., Ed. and P. Overell, "Augmented BNF forSyntax Specifications: ABNF", STD 68, RFC 5234,January 2008.[RFC5646] Phillips, A., Ed. and M. Davis, Ed., "Tags forIdentifying Languages", BCP 47, RFC 5646,September 2009.[USASCII] American National Standards Institute, "Coded Character Set -- 7-bit American Standard Code for InformationInterchange", ANSI X3.4, 1986.7.2. Informative References[Err1912] RFC Errata, Errata ID 1912, RFC 2978,<>.[RFC2045] Freed, N. and N. Borenstein, "Multipurpose InternetMail Extensions (MIME) Part One: Format of InternetMessage Bodies", RFC 2045, November 1996.[RFC2047] Moore, K., "MIME (Multipurpose Internet MailExtensions) Part Three: Message Header Extensions forNon-ASCII Text", RFC 2047, November 1996.[RFC2231] Freed, N. and K. Moore, "MIME Parameter Value andEncoded Word Extensions: Character Sets, Languages, and Continuations", RFC 2231, November 1997.[RFC2277] Alvestrand, H., "IETF Policy on Character Sets andLanguages", BCP 18, RFC 2277, January 1998.[RFC2388] Masinter, L., "Returning Values from Forms: multipart/ form-data", RFC 2388, August 1998.Reschke Standards Track [Page 9]Author’s AddressJulian F. Reschkegreenbytes GmbHHafenweg 16Muenster, NW 48155GermanyEMail: julian.reschke@greenbytes.deURI: http://greenbytes.de/tech/webdav/Reschke Standards Track [Page 10]。

Infoprint 250 導入と計画の手引き第 7 章ホスト

SUBNETMASK
255.255.255.128
Type of service...............: TOS
*NORMAL
Maximum transmission unit.....: MTU
*LIND
Autostart.....................:
AUTOSTART
*YES
: xx.xxx.xxx.xxx
: xx.xxx.xxx.xxx
*
(
)
IEEE802.3
60 1500
: xxxx
48 Infoprint 250
31. AS/400
IP
MTU
1
1
IPDS TCP
CRTPSFCFG (V3R2)
WRKAFP2 (V3R1 & V3R6)
RMTLOCNAME RMTSYS
MODEL
0
Advanced function printing............:
AFP
*YES
AFP attachment........................:
AFPATTACH
*APPC
Online at IPL.........................:
ONLINE
FORMFEED
*CONT
Separator drawer......................:
SEPDRAWER
*FILE
Separator program.....................:
SEPPGM
*NONE
Library.............................:

rfc1137.Mapping Between Full RFC 822 and RFC 822 with Restricted Encoding

Network Working Group S. Kille Request for Comments: 1137 University College London Updates: RFC 976 December 1989 Mapping Between Full RFC 822 and RFC 822 withRestricted EncodingStatus of this MemoThis RFC suggests an electronic mail protocol mapping for theInternet community and UK Academic Community, and requests discussion and suggestions for improvements. This memo does not specify anInternet standard. Distribution of this memo is unlimited.This document describes a set of address mappings which will enableinterworking between systems operating RFC 822 protocols in a general manner, and those environments where transfer of RFC 822 messagesrestricts the character set which can be used in addresses. UUCPtransfer of RFC 822 messages is an important case of this[Crocker82a, Horton86a].SpecificationThis document specifies a mapping between two protocols. Thisspecification should be used when this mapping is performed on theInternet or in the UK Academic Community. This specification may bemodified in the light of implementation experience, but nosubstantial changes are expected.1. IntroductionSome mail networks which use RFC 822 cannot support the fullcharacter set required by all aspects of RFC 822. This documentdescribes a symmetrical mapping between full RFC 822 addressing, and a form for use on these networks. Any addresses within the networks will not use the full RFC 822 addressing, and so any addressesencoded according to this standard will always represent remoteaddresses. This document derives from a mapping originally specified in RFC 987 [Kille86a], where the domain of application was morerestricted. Two terms are now defined:Full RFC 822This implies full support for transfer to and from any legal RFC822 address. In particular, the quoted-string form of local-part must be supported (e.g., <"Joe Soap"@foo.bar>).Kille [Page 1]Restricted RFC 822This implies a subset of RFC 822 addressing. The quoted-stringform of local-part need not be supported. Standard UUCP mailtransfer falls into this category. Restricted RFC 822 isundesirable, but in practice it exists in many places.When a message is transferred from full RFC 822 to restricted RFC 822, and address forms used in full RFC 822 are involved, message loss may occur (e.g., it may not be possible to return an errormessage). This RFC describes a quoting mechanism which may beused to map between full RFC 822 and restricted RFC 822, in order to alleviate this problem.2. EncodingThe RFC 822 EBNF meta notation is used. Any EBNF definitions takenfrom RFC 822 are prefixed by the string "822.".The following EBNF is specified.atom-encoded = *( a-char / a-encoded-char )a-char = <any CHAR except specials (other than "@"and "."), SPACE,CTL, "_", and "#">a-encoded-char = "_" ; (space)/ "#u#" ; (_)/ "#l#" ; <(>/ "#r#" ; <)>/ "#m#" ; (,)/ "#c#" ; (:)/ "#b#" ; (\)/ "#h#" ; (#)/ "#e#" ; (=)/ "#s#" ; (/)/ "#" 3DIGIT "#"The 822.3DIGIT in EBNF.a-encoded-char must have range 0-127, and isinterpreted in decimal as the corresponding ASCII character. Thechoice of special abbreviations (as opposed to decimal encoding)provided is based on the manner in which this mapping is mostfrequently used. There are special encodings for each of thePrintableString characters not in EBNF.a-char, except ".". Space is given a single character encoding, due to its (expected) frequency of use, and backslash as the RFC 822 single quote character.This mapping is used to transform between the two forms of 822.word: 822.quoted-string (restricted RFC 822) and 822.atom (restricted RFC Kille [Page 2]822). To encode (full RFC 822 -> restricted RFC 822), first removeany quoting from any 822.quoted-string. Then, all EBNF.a-char areused directly and all other CHAR are encoded as EBNF.a-encoded-char. To decode (restricted RFC 822 -> full RFC 822): if the address can be parsed as EBNF.encoded-atom reverse the previous mapping. If itcannot be so parsed, map the characters directly.3. ApplicationThis mapping should be used for all addresses, at the MTS or Headerlevel. It is applied to the 822.local-part of the addresses. Forexample:Full RFC 822 Restricted RFC 822Steve.Kille@ <-> Steve.Kille@"Steve Kille"@ <-> Steve_Kille@"argle#˜"@blargle <-> argle#h##126#@blargleReferences[Crocker82a] Crocker, D., "Standard of the Format of ARPA InternetText Messages", RFC 822, August 1982.[Horton86a] Horton, M., "UUCP Mail Interchange Format Standard",RFC 976, February 1986.[Kille86a] Kille, S., "Mapping Between X.400 and RFC 822",UK Academic Community Report (MG.19), RFC 987, June 1986.Security ConsiderationsSecurity issues are not discussed in this memo.Author’s AddressSteve KilleUniversity College LondonGower StreetWC1E 6BTEnglandPhone: +44-1-380-7294EMail: S.Kille@Kille [Page 3]。

rfc3986 uri的正则表达式

rfc3986 URI 的正则表达式1. URI（Uniform Resource Identifier）是统一资源标识符的缩写，它是用于标识某一互联网资源的字符串标识符。

在互联网上，URI 是用来定位资源的，比如网页、图片、视频等。

URI 包括 URL 和 URN两种，其中 URL 是统一资源定位符，可以用来定位一个具体的资源，而 URN 是统一资源名称，用来给资源分配一个唯一的名称。

2. 在 rfc3986 中，定义了 URI 的通用语法和规则，包括 URI 的组成部分、解析规则等。

rfc3986 也规定了URI 的合法字符集和编码方式，以及 URI 的正则表达式。

3. 正则表达式是用于匹配字符串的一种强大工具，可以根据一定的规则从给定的字符串中筛选出符合条件的子串。

在 rfc3986 中，定义了URI 的正则表达式，用来验证一个字符串是否符合 URI 的规范。

4. 根据 rfc3986 中的定义，URI 的通用语法可以用以下正则表达式来表示：```^(([^:/?#]+):)?(\/\/([^/?#]*))?([^?#]*)(\?([^#]*))?(#(.*))?```这个正则表达式从整体上将 URI 分为以下几个部分：- 方案部分（scheme）：以双斜线开头的部分，可以包括字母、数字和特定字符，但不能包括空格或其他非法字符。

- 授权部分（authority）：双斜线后面到路径部分之前的部分，用来表示权限，一般格式为“[user:password]host[:port]”，其中 user 和 password 可选，host 是必须的。

- 路径部分（path）：authority 后面到查询部分之前的部分，用来表示资源的路径，可以包括字母、数字和特定字符。

- 查询部分（query）：以问号开头的部分，用来表达查询参数，可以包括字母、数字和特定字符。

- 片段标识符部分（fragment）：以井号开头的部分，用来表示文档中的某个片段，可以包括字母、数字和特定字符。

rfc相关设置及使用

rfc相关设置及使用RFC（Request for Comments）是一种用于定义互联网协议、标准和相关问题的文档。

RFC的格式由互联网工程任务组（IETF）统一规定，它们记录了网络技术的发展和演进过程。

在本文中，我们将介绍RFC相关的设置和使用。

1. 了解RFC的作用和历史：RFC是由IETF组织制定的一种标准化文档，它记录了互联网协议的设计、开发和演化过程。

RFC起源于20世纪60年代的ARPANET，是一种社区驱动的文档，通过共享和讨论来推动互联网技术的发展。

RFC文档旨在提供指南、建议和最佳实践，帮助网络技术人员解决问题。

2. 寻找和阅读RFC文档：RFC文档可以在互联网上免费获取，IETF的官方网站和其他资源库都有存档。

这些文档按照顺序编号，并且以RFC开头，比如RFC 791定义了IPv4协议。

通过搜索引擎或在IETF网站上使用关键词搜索，可以找到特定主题的RFC文档。

阅读RFC文档时，应该注意文档的状态，有一些可能已经被更新或废弃。

3. 使用RFC文档：RFC文档在网络技术的发展过程中起着重要的指导作用。

它们提供了协议规范、算法实现、安全性和隐私等方面的建议。

网络管理员、网络工程师和开发人员可以使用RFC文档来了解和理解特定协议或标准的设计原理和要求。

此外，RFC文档还常用于进行互联网协议的实现、编程和配置。

4. 参与RFC的制定过程：RFC并不是静止的文件，而是一个持续演进的过程。

任何人都可以参与到RFC的制定过程中。

要参与RFC的制定，可以加入IETF并参与相关的工作组或邮件列表。

通过这种方式，个人可以提出改进建议，参与讨论和标准化的制定。

5. 遵循RFC的指导原则：在网络技术领域，遵循RFC的指导原则是至关重要的。

这些指导原则包括设计原则、协议分层、安全性和互操作性等要求。

遵循RFC的指导原则可以确保网络协议的正确性、稳定性和可靠性，同时也可以促进网络技术的发展和创新。

总结起来，RFC在互联网技术领域起着重要的作用，它们记录了互联网协议的发展历程和指导原则。

日文编码系统与乱码关系

日文编码系统与乱码关系
日文编码系统与乱码之间的关系是一个比较复杂的话题。

日文可以使用多种编码系统，其中最常见的是Shift JIS、EUC-JP和UTF-8。

这些编码系统在表示日文字符时使用不同的规则和格式。

当日文文件以错误的编码方式打开时，就会出现乱码。

这是因为计算机无法正确解释以错误编码方式表示的字符。

例如，如果一个以UTF-8编码的日文文件被错误地以Shift JIS编码方式打开，文件中的日文字符就会显示为乱码。

乱码问题还可能出现在文本传输过程中。

当文本从一个以一种编码方式保存的系统传输到另一个以不同编码方式保存的系统时，如果接收系统无法正确识别编码方式，就会导致乱码。

为了避免乱码问题，我们需要确保在处理日文文本时使用正确的编码方式。

在编辑、保存和传输日文文件时，需要确保所有的操作都使用统一的编码方式，以确保日文字符能够被正确地显示和处理。

总之，日文编码系统与乱码之间的关系在于正确的编码方式能
够确保日文字符能够被正确地显示和处理，而错误的编码方式则会导致乱码问题的出现。

因此，正确理解和使用日文编码系统对于日文文本的处理至关重要。

HTTP常见状态码详细解析

HTTP常见状态码详细解析HTTP状态码（英语：HTTP Status Code）是⽤以表⽰⽹页服务器超⽂本传输协议响应状态的3位数字代码。

它由 RFC 2616 规范定义的，并得到 RFC 2518、RFC 2817、RFC 2295、RFC 2774 与 RFC 4918 等规范扩展。

HTTP状态码负责表⽰客户端HTTP请求的返回结果、标记服务端的处理是否正常、通知出现的错误等⼯作。

状态码的类别的由三位数字和原因短语组成，数字的第⼀位数字表⽰响应的类别，后⾯两位⽆类别。

以下有五种类别。

另外只要遵循状态码类别的定义，即使改变RFC2616中定义的状态码，或者服务端⾃⾏创建状态码都可以。

1XX类别：informational 信息性状态码原因短语：接收的请求正在处理2XX类别：success 成功状态码原因短语：请求正常处理完毕3XX类别：redirection 重定向状态码原因短语：需要进⾏附加操作以完成请求4XX类别：client error 客户端错误状态码原因短语：服务器⽆法处理请求5XX类别：server error 服务器错误状态码原因短语：服务器处理请求出错在RFC2616上的http状态码达到40多种，在加上WEBDAV和附加HTTP状态码（RFC6585）等扩展，就有60多种，但常⽤的有以下这些，接下来让我们分别来学习下。

（注：以下的使⽤场景只是举例，不包括所有使⽤场景）1xx Informational 信息响应1XX 是信息响应，表⽰接收的请求正在被处理。

100 Continue （继续）响应结果：信息型状态响应码表⽰⽬前为⽌⼀切正常, 客户端应该继续请求, 如果已完成请求则忽略.使⽤场景：为了让服务器检查请求的⾸部, 客户端必须在发送请求实体前, 在初始化请求中发送 Expect: 100-continue ⾸部并接收 100 Continue 响应状态码.101 Switching Protocols （协议切换）响应结果：表⽰服务器应客户端升级协议的请求（Upgrade请求头）正在进⾏协议切换。

rfc1468.Japanese Character Encoding for Internet Messages

Network Working Group J. Murai Request for Comments: 1468 Keio University M. Crispin Panda Programming E. van der Poel June 1993 Japanese Character Encoding for Internet MessagesStatus of this MemoThis memo provides information for the Internet community. It doesnot specify an Internet standard. Distribution of this memo isunlimited.IntroductionThis document describes the encoding used in electronic mail [RFC822] and network news [RFC1036] messages in several Japanese networks. It was first specified by and used in JUNET [JUNET]. The encoding is now also widely used in Japanese IP communities.The name given to this encoding is "ISO-2022-JP", which is intendedto be used in the "charset" parameter field of MIME headers (see[MIME1] and [MIME2]).DescriptionThe text starts in ASCII [ASCII], and switches to Japanese characters through an escape sequence. For example, the escape sequence ESC $ B (three bytes, hexadecimal values: 1B 24 42) indicates that the bytes following this escape sequence are Japanese characters, which areencoded in two bytes each. To switch back to ASCII, the escapesequence ESC ( B is used.The following table gives the escape sequences and the character sets used in ISO-2022-JP messages. The ISOREG number is the registrationnumber in ISO’s registry [ISOREG].Esc Seq Character Set ISOREGESC ( B ASCII 6ESC ( J JIS X 0201-1976 ("Roman" set) 14ESC $ @ JIS X 0208-1978 42ESC $ B JIS X 0208-1983 87Note that JIS X 0208 was called JIS C 6226 until the name was changed Murai, Crispin & van der Poel [Page 1]on March 1st, 1987. Likewise, JIS C 6220 was renamed JIS X 0201.The "Roman" character set of JIS X 0201 [JISX0201] is identical toASCII except for backslash () and tilde (˜). The backslash isreplaced by the Yen sign, and the tilde is replaced by overline. This set is Japan’s national variant of ISO 646 [ISO646].The JIS X 0208 [JISX0208] character sets consist of Kanji, Hiragana,Katakana and some other symbols and characters. Each character takesup two bytes.For further details about the JIS Japanese national character setstandards, refer to [JISX0201] and [JISX0208]. For furtherinformation about the escape sequences, see [ISO2022] and [ISOREG].If there are JIS X 0208 characters on a line, there must be a switchto ASCII or to the "Roman" set of JIS X 0201 before the end of theline (i.e., before the CRLF). This means that the next line starts in the character set that was switched to before the end of the previous line.Also, the text must end in ASCII.Other restrictions are given in the Formal Syntax below.Formal SyntaxThe notational conventions used here are identical to those used inRFC 822 [RFC822].The * (asterisk) convention is as follows:l*m somethingmeaning at least l and at most m somethings, with l and m takingdefault values of 0 and infinity, respectively.message = headers 1*( CRLF *single-byte-char *segmentsingle-byte-seq *single-byte-char ); see also [MIME1] "body-part" ; note: must end in ASCIIheaders = <see [RFC822] "fields" and [MIME1] "body-part"> segment = single-byte-segment / double-byte-segmentsingle-byte-segment = single-byte-seq 1*single-byte-charMurai, Crispin & van der Poel [Page 2]double-byte-segment = double-byte-seq 1*( one-of-94 one-of-94 )single-byte-seq = ESC "(" ( "B" / "J" )double-byte-seq = ESC "$" ( "@" / "B" )CRLF = CR LF; ( Octal, Decimal.) ESC = <ISO 2022 ESC, escape> ; ( 33, 27.) SI = <ISO 2022 SI, shift-in> ; ( 17, 15.) SO = <ISO 2022 SO, shift-out> ; ( 16, 14.) CR = <ASCII CR, carriage return>; ( 15, 13.) LF = <ASCII LF, linefeed> ; ( 12, 10.) one-of-94 = <any one of 94 values> ; (41-176, 33.-126.) 7BIT = <any 7-bit value> ; ( 0-177, 0.-127.) single-byte-char = <any 7BIT, including bare CR & bare LF, but NOT including CRLF, and not including ESC, SI, SO> MIME ConsiderationsThe name given to the JUNET character encoding is "ISO-2022-JP". This name is intended to be used in MIME messages as follows:Content-Type: text/plain; charset=iso-2022-jpThe ISO-2022-JP encoding is already in 7-bit form, so it is notnecessary to use a Content-Transfer-Encoding header. It should benoted that applying the Base64 or Quoted-Printable encoding willrender the message unreadable in current JUNET software.ISO-2022-JP may also be used in MIME Part 2 headers. The "B"encoding should be used with ISO-2022-JP text.Background InformationThe JUNET encoding was described in the JUNET User’s Guide [JUNET](JUNET Riyou No Tebiki Dai Ippan).The encoding is based on the particular usage of ISO 2022 announced Murai, Crispin & van der Poel [Page 3]by 4/1 (see [ISO2022] for details). However, the escape sequencenormally used for this announcement is not included in ISO-2022-JPmessages.The Kana set of JIS X 0201 is not used in ISO-2022-JP messages.In the past, some systems erroneously used the escape sequence ESC ( H in JUNET messages. This escape sequence is officially registeredfor a Swedish character set [ISOREG], and should not be used in ISO- 2022-JP messages.Some systems do not distinguish between ESC ( B and ESC ( J orbetween ESC $ @ and ESC $ B for display. However, when relaying amessage to another system, the escape sequences must not be alteredin any way.The human user (not implementor) should try to keep lines within 80display columns, or, preferably, within 75 (or so) columns, to allow insertion of ">" at the beginning of each line in excerpts. Each JIS X 0208 character takes up two columns, and the escape sequences donot take up any columns. The implementor is reminded that JIS X 0208 characters take up two bytes and should not be split in the middle to break lines for displaying, etc.The JIS X 0208 standard was revised in 1990, to add two characters at the end of the table. Although ISO 2022 specifies special additional escape sequences to indicate the use of revised character sets, it is suggested here not to make use of this special escape sequence inISO-2022-JP text, even if the two characters added to JIS X 0208 in1990 are used.For further information about Japanese character encodings such as PC codes, FTP locations of implementations, etc, see "ElectronicHandling of Japanese Text" [JPN.INF].References[ASCII] American National Standards Institute, "Coded character set-- 7-bit American national standard code for informationinterchange", ANSI X3.4-1986.[ISO646] International Organization for Standardization (ISO),"Information technology -- ISO 7-bit coded character set forinformation interchange", International Standard, Ref. No. ISO/IEC646:1991.[ISO2022] International Organization for Standardization (ISO),"Information processing -- ISO 7-bit and 8-bit coded character sets Murai, Crispin & van der Poel [Page 4]-- Code extension techniques", International Standard, Ref. No. ISO2022-1986 (E).[ISOREG] International Organization for Standardization (ISO),"International Register of Coded Character Sets To Be Used WithEscape Sequences".[JISX0201] Japanese Standards Association, "Code for InformationInterchange", JIS X 0201-1976.[JISX0208] Japanese Standards Association, "Code of the Japanesegraphic character set for information interchange", JIS X 0208-1978,-1983 and -1990.[JPN.INF] Ken R. Lunde <lunde@>, "Electronic Handling ofJapanese Text", March 1992,(128.101.24.1):pub/lunde/japan[123].inf[JUNET] JUNET Riyou No Tebiki Sakusei Iin Kai (JUNET User’s GuideDrafting Committee), "JUNET Riyou No Tebiki (Dai Ippan)" ("JUNETUser’s Guide (First Edition)"), February 1988.[MIME1] Borenstein N., and N. Freed, "MIME (MultipurposeInternet Mail Extensions): Mechanisms for Specifying andDescribing the Format of Internet Message Bodies", RFC 1341,Bellcore, Innosoft, June 1992.[MIME2] Moore, K., "Representation of Non-ASCII Text in InternetMessage Headers", RFC 1342, University of Tennessee, June 1992.[RFC822] Crocker, D., "Standard for the Format of ARPA InternetText Messages", STD 11, RFC 822, UDEL, August 1982.[RFC1036] Horton M., and R. Adams, "Standard for Interchange of USENET Messages", RFC 1036, AT&T Bell Laboratories, Center for SeismicStudies, December 1987.AcknowledgementsMany people assisted in drafting this document. The authors wish tothank in particular Akira Kato, Masahiro Sekiguchi and Ken’ichiHanda.Security ConsiderationsSecurity issues are not discussed in this memo.Murai, Crispin & van der Poel [Page 5]Authors’ AddressesJun MuraiKeio University5322 Endo, FujisawaKanagawa 252 JapanFax: +81 466 49 1101EMail: jun@wide.ad.jpMark CrispinPanda Programming6158 Lariat Loop NEBainbridge Island, WA 98110-2098USAPhone: +1 206 842 2385EMail: MRC@Erik M. van der PoelA-105 Park Avenue4-4-10 Ohta, KisarazuChiba 292 JapanPhone: +81 438 22 5836Fax: +81 438 22 5837EMail: erik@poel.juice.or.jpMurai, Crispin & van der Poel [Page 6]。

RFC2236

当查询者在其接口上接收到了组成员离开组的消息之后，它发送 [最后成员查询计数 ] 特定组成员查询消息[最后成员查询间隔] 给正离开的组。这些特定组查询有最大的响应时间(设为最后成员查询间隔)。如果在最后查询的响应时间之后，没有报告者接到消息，路由器则会假定该组没有本地的成员。在该时间内，任一个查询者到非查询者的传送都会忽略，一个路由器会继续发送特定组的查询。
"SHOULD", "SHOULD NOT", "RECOMMENDED", "MAY", and "OPTIONAL" 均在RFC 2119 [RFC 2119]有详细说明。
2. 介绍
Internet组管理协议 (IGMP)在IP主机上应用，并向任一个邻近的路由器报告他们的组播成员关系。该备忘录仅描述了 IGMP 在主机和路由器之间如何确定其组成员关系，在此路由器和组播成员主机的行为相近。IGMP 也用于两个路由器之间，但不在此进行讨论。
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
2.1. 类型
有3种 IGMP 消息和主机与路由器的交互有关：
0x11 = 成员关系查询
有两个成员关系查询的子类型：
- 一般查询，用于了解一个组中是否有成员在相邻的网络中。
该文档是Internet工程技术组织一个域内组播的技术标准。如有任何注释应向idmr@邮件列表或其作者提出。

rfc 3629规则

rfc 3629规则RFC 3629是关于UTF-8字符编码的规范。

以下是关于该规范中定义的规则的简要概述：1.基本多语言平面（BMP）：UTF-8只定义了基本多语言平面的字符编码。

所有的U+0000到U+FFFF的Unicode码位都由两个字节（16位）表示。

2.字节顺序标记（BOM）：UTF-8编码的文件可以使用字节顺序标记（BOM）来指示字节顺序。

BOM是一个字节序列（0xEF,0xBB,0xBF），用于在字节流中标识UTF-8编码的文本。

3.起始字节：UTF-8编码的起始字节是用来标识一个字符的开始。

起始字节为0xC0到0xFD的字符由两个字节组成，起始字节为0x00到0x7F的字符由一个字节组成。

4.后续字节：后续字节用于扩展多字节字符。

其第一个二进制位为1，接下来的二进制位用于表示额外的字节数和偏移量。

5.非法的UTF-8序列：不符合UTF-8编码规则的字节序列被认为是无效或非法的。

例如，一个以0xC0开始的字节序列，其随后的字节没有以10开头，或者一个以0xF5开始的字节序列，其随后的字节没有以11开头，都是非法的UTF-8序列。

6.字符编码规则：根据不同的Unicode码位范围，UTF-8采用不同的字节数来编码字符。

例如，码位在U+0000到U+007F之间的字符使用一个字节编码（起始字节为0x00到0x7F），码位在U+0080到U+07FF之间的字符使用两个字节编码（起始字节为0xC2到0xDF），码位在U+0800到U+FFFF之间的字符使用三个字节编码（起始字节为0xE0到0xEF）。

以上是RFC 3629中定义的UTF-8编码规则的简要概述。

如需了解更多详细信息，请参考官方文档或相关资料。

rfc 5322标准

rfc 5322标准
RFC 5322 是一项Internet 标准，它规定了电子邮件的格式、结构和内容。

该标准于2008年发布，取代了之前的RFC 2822，并进一步扩展了电子邮件的语法和语义。

以下是RFC 5322 中的一些关键内容：
电子邮件地址格式：它定义了电子邮件地址的结构和语法，包括邮件头部（header）和邮件体（body）的各个部分。

邮件头部：包括发件人（From）、收件人（To）、抄送（CC）、密送（BCC）、主题（Subject）、日期（Date）等信息，以及其他可能的标头字段。

邮件体：邮件体包括邮件的正文内容，可以是纯文本、HTML 格式、附件等。

地址标准化：RFC 5322 规定了电子邮件地址的标准化格式，包括邮件用户名和邮件域名的结构和语法规则。

消息结构：它定义了电子邮件消息的结构，包括消息头部、消息体和附件的组织方式。

字符编码和传输：RFC 5322 规定了邮件内容的字符编码和传输方式，以确保邮件在网络上的可靠传输。

邮件格式标准化：RFC 5322 对邮件格式进行了标准化，以确保不同邮件客户端和邮件服务器之间的互操作性和兼容性。

总的来说，RFC 5322 标准化了电子邮件的格式、结构和内容，使得电子邮件系统能够在全球范围内进行通信和交换，为互联网邮件提供了统一的基础规范。

1。

request库默认使用的编码方式

request库默认使用的编码方式
request库默认使用的编码方式是UTF-8。

在使用Python的request库发送HTTP请求时，默认情况下，request库会使用UTF-8编码对请求的数据进行编码和解码。

这意味着，如果您发送的请求中包含非ASCII字符（如中文、日文、俄文等），request库会自动将这些字符转换为UTF-8编码进行传输。

UTF-8是一种通用的字符编码标准，它可以表示世界上几乎所有的字符，包括ASCII字符和非ASCII字符。

因此，使用UTF-8编码可以确保请求中的文本数据能够正确传输和处理，而不会出现乱码或其他编码相关的问题。

如果需要使用其他编码方式，可以通过设置request库的headers 来指定编码方式。

例如，可以在请求头中设置'Content-Type'字段为'application/x-www-form-urlencoded;charset=utf-8'，其中'charset=utf-8'指定了使用UTF-8编码。

另外，如果您接收到的响应数据使用了其他编码方式，request库也会根据响应头中的'Content-Type'字段中的编码信息进行自动解码，以确保能够正确地处理响应数据。

如果需要自定义解码方式，可以使用response对象的`content.decode()`方法手动解码响应数
据。

综上所述，request库默认使用UTF-8编码方式对请求和响应数据进行处理，这有助于确保数据的正确传输和处理。

如果需要使用其他编码方式，可以通过设置请求头或手动解码来实现。