A mailbox provider, mail service provider or, somewhat improperly, email service provider is a provider of
email
Electronic mail (email or e-mail) is a method of exchanging messages ("mail") between people using electronic devices. Email was thus conceived as the electronic ( digital) version of, or counterpart to, mail, at a time when "mail" meant ...
hosting. It implements
email servers to send, receive, accept, and store email for other organizations or
end users
In product development, an end user (sometimes end-user) is a person who ultimately uses or is intended to ultimately use a product. The end user stands in contrast to users who support or maintain the product, such as sysops, system administrato ...
, on their behalf.
The term "mail service provider" was coined in the Internet Mail Architecture document .
Types
There are various kinds of email providers. There are paid and free ones, possibly sustained by advertising. Some allow anonymous users, whereby a single user can get multiple, apparently unrelated accounts. Some require full identification credentials; for example, a company may provide email accounts to full-time staff only. Often, companies, universities, organizations, groups, and individuals that manage their mail servers themselves adopt naming conventions that make it straightforward to identify who is the owner of a given email address. Besides control of the local names,
insourcing
Outsourcing is an agreement in which one company hires another company to be responsible for a planned or existing activity which otherwise is or could be carried out internally, i.e. in-house, and sometimes involves transferring employees and ...
may provide for data confidentiality, network traffic optimization, and fun.
Mailbox providers typically accomplish their task by implementing
Simple Mail Transfer Protocol
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 typica ...
(SMTP) and possibly providing access to messages through
Internet Message Access Protocol
In computing, the Internet Message Access Protocol (IMAP) is an Internet standard protocol used by email clients to retrieve email messages from a mail server over a TCP/IP connection. IMAP is defined by .
IMAP was designed with the goal of per ...
(IMAP), the
Post Office Protocol
In computing, the Post Office Protocol (POP) is an application-layer Internet standard protocol used by e-mail clients to retrieve e-mail from a mail server. POP version 3 (POP3) is the version in common use, and along with IMAP the most common p ...
,
Webmail
Webmail (or web-based email) is an email service that can be accessed using a standard web browser. It contrasts with email service accessible through a specialised email client software. Examples of webmail providers are 1&1 Ionos, AOL Mail, G ...
, or a proprietary protocol. Parts of the task can still be outsourced, for example virus and spam filtering of incoming mail, or authentication of outgoing mail.
ISP-based email
Many mailbox providers are also access providers. Not the core product, their email services could lack some interesting features, such as IMAP,
Transport Layer Security
Transport Layer Security (TLS) is a cryptographic protocol designed to provide communications security over a computer network. The protocol is widely used in applications such as email, instant messaging, and voice over IP, but its use in securi ...
, or
SMTP Authentication
SMTP Authentication, often abbreviated SMTP AUTH, is an extension of the Simple Mail Transfer Protocol (SMTP) whereby a client may log in using any authentication mechanism supported by the server. It is mainly used by submission servers, where au ...
—in fact, an ISP can do without the latter, as it can recognize its clients by the IP addresses it assigns them.
Free mail providers
AOL Mail
AOL Mail (stylized as Aol Mail.) is a free web-based email service provided by AOL, a division of Yahoo.
Features
AOL Mail has the following features available:
* Email attachment limit: 25 MB
* Max mailbox size: Unlimited
* Supported protoc ...
,
Hotmail
Outlook.com is a webmail service that is part of the Microsoft 365 product family. It offers mail, Calendaring software, calendaring, Address book, contacts, and Task management, tasks services.
Founded in 1996 by Sabeer Bhatia and Jack Smit ...
,
Lycos
Lycos, Inc., is a web search engine and web portal established in 1994, spun out of Carnegie Mellon University. Lycos also encompasses a network of email, web hosting, social networking, and entertainment websites. The company is based in Walth ...
,
Mail.com
mail.com is a web portal and web-based email service provider owned by the internet company 1&1 Mail & Media Inc., headquartered in Philadelphia, Pennsylvania, United States. 1&1 Mail & Media Inc. is a subsidiary of United Internet Group, a pu ...
,
Yahoo! Mail
Yahoo! Mail is an email service launched on October 8, 1997, by the American company Yahoo (2017–present), Yahoo, Inc. The service is free for personal use, with an optional monthly fee for additional features. Business email was previously av ...
, launched in the 1990s, are among the early providers of free email accounts, joined by
Gmail
Gmail is a free email service provided by Google. As of 2019, it had 1.5 billion active users worldwide. A user typically accesses Gmail in a web browser or the official mobile app. Google also supports the use of email clients via the POP an ...
in 2004. They attract users because they are free and can advertise their service on every message. According to Jurvetson, Hotmail grew from zero to 12 million users in 18 months. That was before it was bought by Microsoft.
Premium email services
These are the paid equivalent of free mail providers. That is, a better alternative to ISP-based email. Much less popular than free mail, they target a niche of users.
Vanity email
It is also possible to run a shim service, providing no access but just forwarding all messages to another account, which does not lend itself to direct use, for example because it is temporary or just less appealing.
Role as identifier
A mailbox provider is the administrator of the registered
domain name
A domain name is a string that identifies a realm of administrative autonomy, authority or control within the Internet. Domain names are often used to identify services provided through the Internet, such as websites, email services and more. As ...
that forms the domain-part of its
email address
An email address identifies an email box to which messages are delivered. While early messaging systems used a variety of formats for addressing, today, email addresses follow a set of specific rules originally standardized by the Internet Engineer ...
es. As such, it controls the
MX record
A mail exchanger record (MX record) specifies the mail server responsible for accepting email messages on behalf of a domain name. It is a resource record in the Domain Name System (DNS). It is possible to configure several MX records, typically p ...
s that specify which hosts will receive email destined to those addresses. The operators of those hosts define the meaning of the local-part of an address by associating it to a mailbox, which in turn can be associated to a user.
The mailbox provider also specifies how users can read their mail, possibly creating
SRV record
A Service record (SRV record) is a specification of data in the Domain Name System defining the location, i.e., the hostname and port number, of servers for specified services. It is defined iRFC 2782 and its type code is 33. Some Internet protoco ...
s to ease email client configuration, or giving detailed instructions.
Email addresses are convenient tokens for identifying people, even at web sites unrelated to email. In fact, they are unique, and allow password reminders to be sent at will.
From a bureaucracy-oriented point of view, there is no formal undertaking beyond domain name registration. This role is based on
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 a ...
standards, and, unlike
X.400 and other
ITU-T
The ITU Telecommunication Standardization Sector (ITU-T) is one of the three sectors (divisions or units) of the International Telecommunication Union (ITU). It is responsible for coordinating standards for telecommunications and Information Commu ...
works, in and of itself requires no arrangements with local authorities. The notion of Administration Management Domain (ADMD) is derived afterwards, from empirical evidence.
However, local authorities concerned with
Internet privacy
Internet privacy involves the right or mandate of personal privacy concerning the storing, re-purposing, provision to third parties, and displaying of information pertaining to oneself via Internet. Internet privacy is a subset of data privacy. Pr ...
issues may add rules and requisites on top of the original Internet email design.
See also
*
Email mailbox A mailboxISO/IEC 2382:2015 (also electronic mailbox, email box, email mailbox, e-mailbox) is the destination to which electronic mail messages are delivered.
It is the equivalent of a letter box in the postal system.
Definitions
A mailbox is identi ...
*
Internet service provider
An Internet service provider (ISP) is an organization that provides services for accessing, using, or participating in the Internet. ISPs can be organized in various forms, such as commercial, community-owned, non-profit, or otherwise private ...
*
Email hosting service
An email hosting service is an Internet hosting service that operates email servers.
Features
Email hosting services usually offer premium email as opposed to advertisement-supported free email or free webmail. Email hosting services thus diff ...
*
Premium email
Electronic mail (email or e-mail) is a method of exchanging messages ("mail") between people using electronic devices. Email was thus conceived as the electronic ( digital) version of, or counterpart to, mail, at a time when "mail" meant ...
*
Web mail server
References
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Email