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Author Domain Signing Practices
In computing, Author Domain Signing Practices (ADSP) is an optional extension to the DKIM E-mail authentication scheme, whereby a domain can publish the signing practices it adopts when relaying mail on behalf of associated authors. ADSP was adopted as a standards track RFC 5617 in August 2009, but declared "Historic" in November 2013 after "...almost no deployment and use in the 4 years since...". Concepts Author address The ''author address'' is the one specified in the header field defined in RFC 5322. In the unusual cases where more than one address is defined in that field, RFC 5322 provides for a field to be used instead. The domains in 5322-''From'' addresses are not necessarily the same as in the more elaborated ''Purported Responsible Address'' covered by Sender ID specified in RFC 4407. The domain in a 5322-''From'' address is also not necessarily the same as in the ''envelope sender'' address defined in RFC 5321, also known as SMTP MAIL FROM, envelope-''From'', ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
DomainKeys
DomainKeys (informally ''DK'') is a deprecated e-mail authentication system designed by Yahoo to verify the domain name of an e-mail sender and the message integrity. Aspects of DomainKeys, along with parts of Identified Internet Mail, were combined to create DomainKeys Identified Mail (DKIM),Delany, Mark (May 22, 2007)"One small step for email, one giant leap for Internet safety" Yahoo! corporate blog. Delany is credited as Chief Architect, inventor of DomainKeys. which is now widely used. Both DomainKeys and DKIM were published in May 2007, DomainKeys as an "historical" protocol, and DKIM as its standards-track replacement. See also * Sender ID * Author Domain Signing Practices * Sender Policy Framework Sender Policy Framework (SPF) is an email authentication method designed to detect forging sender addresses during the delivery of the email. SPF alone, though, is limited to detecting a forged sender claim in the envelope of the email, which is ... (SPF) References Externa ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
IETF
The Internet Engineering Task Force (IETF) is a standards organization for the Internet and is responsible for the technical standards that make up the Internet protocol suite (TCP/IP). It has no formal membership roster or requirements and all its participants are volunteers. Their work is usually funded by employers or other sponsors. The IETF was initially supported by the federal government of the United States but since 1993 has operated under the auspices of the Internet Society, an international non-profit organization. Organization The IETF is organized into a large number of working groups and birds of a feather informal discussion groups, each dealing with a specific topic. The IETF operates in a bottom-up task creation mode, largely driven by these working groups. Each working group has an appointed chairperson (or sometimes several co-chairs); a charter that describes its focus; and what it is expected to produce, and when. It is open to all who want to particip ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Sender ID
Sender ID is an historic anti- spoofing proposal from the former MARID IETF working group that tried to join Sender Policy Framework (SPF) and Caller ID. Sender ID is defined primarily in Experimental RFC 4406, but there are additional parts in RFC 4405, RFC 4407 and RFC 4408. Principles of operation Sender ID is heavily based on SPF, with only a few additions. Sender ID tries to improve on SPF: SPF does not verify the header addresses (of which there can be more than one) that indicate the claimed sending party. One of these header addresses is typically displayed to the user and may be used to reply to emails. These header addresses can be different from the address that SPF tries to verify; that is, SPF verifies only the "MAIL FROM" address, also called the envelope sender. However, there are many similar email header fields that all contain sending party information; therefore Sender ID defines in RFC 4407 a Purported Responsible Address (PRA) as well as a set of heuristi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Envelope Sender
{{No footnotes, date=June 2016 A bounce address is an email address to which bounce messages are delivered. There are many variants of the name, none of them used universally, including return path, reverse path, envelope from, envelope sender, MAIL FROM, 5321-FROM, return address, From_, Errors-to, etc. It is not uncommon for a single document to use several of these names. All of these names refer to the email address provided with the MAIL FROM command during the SMTP session. Background information Ordinarily, the bounce address is not seen by email users and, without standardization of the name, it may cause confusion. If an email message is thought of as resembling a traditional paper letter in an envelope, then the "header fields", such as To:, From:, and Subject:, along with the body of the message are analogous to the letterhead and body of a letter - and are normally all presented and visible to the user. However, the envelope in this analogy is the contents of the M ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
SMTP
The Simple Mail Transfer Protocol (SMTP) is an Internet standard communication protocol for electronic mail transmission. Mail servers and other message transfer agents use SMTP to send and receive mail messages. User-level email clients typically use SMTP only for sending messages to a mail server for relaying, and typically submit outgoing email to the mail server on port 587 or 465 per . For retrieving messages, IMAP (which replaced the older POP3) is standard, but proprietary servers also often implement proprietary protocols, e.g., Exchange ActiveSync. SMTP's origins began in 1980, building on concepts implemented on the ARPANET since 1971. It has been updated, modified and extended multiple times. The protocol version in common use today has extensible structure with various extensions for authentication, encryption, binary data transfer, and internationalized email addresses. SMTP servers commonly use the Transmission Control Protocol on port number 25 (for plaintext) and ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Sender Policy Framework
Sender Policy Framework (SPF) is an email authentication method designed to detect forging sender addresses during the delivery of the email. SPF alone, though, is limited to detecting a forged sender claim in the envelope of the email, which is used when the mail gets bounced. Only in combination with DMARC can it be used to detect the forging of the visible sender in emails (email spoofing), a technique often used in phishing and email spam. SPF allows the receiving mail server to check during mail delivery that a mail claiming to come from a specific domain is submitted by an IP address authorized by that domain's administrators. The list of authorized sending hosts and IP addresses for a domain is published in the DNS records for that domain. Sender Policy Framework is defined in RFC 7208 dated April 2014 as a "proposed standard". History The first public mention of the concept was in 2000 but went mostly unnoticed. No mention was made of the concept again until a first att ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Message Submission Agent
A message submission agent (MSA), or mail submission agent, is a computer program or software agent that receives electronic mail messages from a mail user agent (MUA) and cooperates with a mail transfer agent (MTA) for delivery of the mail. It uses ESMTP, a variant of the Simple Mail Transfer Protocol (SMTP), as specified in RFC 6409. Many MTAs perform the function of an MSA as well, but there are also programs that are specially designed as MSAs without full MTA functionality. Historically, in Internet mail, both MTA and MSA functions use port number 25, but the official port for MSAs is 587. The MTA accepts a user's incoming mail, while the MSA accepts a user's outgoing mail. Benefits Separation of the MTA and MSA functions produces several benefits. One benefit is that an MSA, since it is interacting directly with the author's MUA, can correct minor errors in a message's format (such as a missing ''Date'', ''Message-ID'', ''To'' fields, or an address with a missing domain ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Domain Name System
The Domain Name System (DNS) is a hierarchical and distributed naming system for computers, services, and other resources in the Internet or other Internet Protocol (IP) networks. It associates various information with domain names assigned to each of the associated entities. Most prominently, it translates readily memorized domain names to the numerical IP addresses needed for locating and identifying computer services and devices with the underlying network protocols. The Domain Name System has been an essential component of the functionality of the Internet since 1985. The Domain Name System delegates the responsibility of assigning domain names and mapping those names to Internet resources by designating authoritative name servers for each domain. Network administrators may delegate authority over sub-domains of their allocated name space to other name servers. This mechanism provides distributed and fault tolerance, fault-tolerant service and was designed to avoid a single ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
DMARC
Domain-based Message Authentication, Reporting and Conformance (DMARC) is an email authentication protocol. It is designed to give email domain owners the ability to protect their domain from unauthorized use, commonly known as email spoofing. The purpose and primary outcome of implementing DMARC is to protect a domain from being used in business email compromise attacks, phishing email, email scams and other cyber threat activities. Once the DMARC DNS entry is published, any receiving email server can authenticate the incoming email based on the instructions published by the domain owner within the DNS entry. If the email passes the authentication, it will be delivered and can be trusted. If the email fails the check, depending on the instructions held within the DMARC record the email could be delivered, quarantined or rejected. For example, one email forwarding service delivers the mail, but as "From: no-reply@". DMARC extends two existing email authentication mechanisms, Se ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Domainkeys
DomainKeys (informally ''DK'') is a deprecated e-mail authentication system designed by Yahoo to verify the domain name of an e-mail sender and the message integrity. Aspects of DomainKeys, along with parts of Identified Internet Mail, were combined to create DomainKeys Identified Mail (DKIM),Delany, Mark (May 22, 2007)"One small step for email, one giant leap for Internet safety" Yahoo! corporate blog. Delany is credited as Chief Architect, inventor of DomainKeys. which is now widely used. Both DomainKeys and DKIM were published in May 2007, DomainKeys as an "historical" protocol, and DKIM as its standards-track replacement. See also * Sender ID * Author Domain Signing Practices * Sender Policy Framework Sender Policy Framework (SPF) is an email authentication method designed to detect forging sender addresses during the delivery of the email. SPF alone, though, is limited to detecting a forged sender claim in the envelope of the email, which is ... (SPF) References Externa ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Eric Allman
Eric Paul Allman (born September 2, 1955) is an American computer programmer who developed sendmail and its precursor delivermail in the late 1970s and early 1980s at UC Berkeley. In 1998, Allman and Greg Olson co-founded the company Sendmail, Inc. Education and training Born in El Cerrito, California, Allman knew from an early age that he wanted to work in computing, breaking into his high school's mainframe and later using the UC Berkeley computing center for his computing needs. In 1973, he entered UC Berkeley, just as the Unix operating system began to become popular in academic circles. He earned B.S. and M.S. degrees from UC Berkeley in 1977 and 1980 respectively. Sendmail and Syslog As the Unix source code was available at Berkeley, the local hackers quickly made many extensions to the AT&T code. One such extension was ''delivermail'', which in 1981 turned into ''sendmail''. As an MTA, it was designed to deliver email over the still relatively small (as compared to to ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Sendmail
Sendmail is a general purpose internetwork email routing facility that supports many kinds of mail-transfer and delivery methods, including the Simple Mail Transfer Protocol (SMTP) used for email transport over the Internet. A descendant of the ''delivermail'' program written by Eric Allman, Sendmail is a well-known project of the free and open source software and Unix communities. It has spread both as free software and proprietary software. Overview Allman had written the original ARPANET delivermail which shipped in 1979 with 4.0 and 4.1 BSD. He wrote Sendmail as a derivative of delivermail in the early 1980s at UC Berkeley. It shipped with BSD 4.1c in 1983, the first BSD version that included TCP/IP protocols. In 1996, approximately 80% of the publicly reachable mail-servers on the Internet ran Sendmail. More recent surveys have suggested a decline, with 3.64% of mail servers in March 2021 detected as running Sendmail in a study performed by E-Soft, Inc. A previous survey ( ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
