The Applications Area of the IETF develops protocols that underlie applications that might be seen by end users. (SMTP, for example, is used by electronic mail, and HTTP by the web; both are application layer protocols.) The Applications Area rarely develops actual applications; instead, its protocols are used as building blocks for specific applications developed elsewhere.

The type of issues handled by the Applications Area have been a key part of the Internet's history from the beginning. For example, document RFC 2 from 1969 focuses on how to use NLS (a bibliographic system) remotely.

Big Applications Area topics of today include spam (dealt with in part by the "marid" working group, also referred to as MTA Authorization Records in DNS), geographic locators (dealt with by "geopriv" working group).

As explained in the Charter for the Geographic Location/Privacy Working Group:

"As more and more resources become available on the Internet, some applications need to acquire geographic location information about certain resources or entities. These applications include navigation, emergency services, management of equipment in the field, and other location-based services.

"But while the formatting and transfer of such information is in some sense a straightforward process, the implications of doing it, especially in regards to privacy and security, are anything but.

"The primary task of this working group will be to assess the the authorization, integrity and privacy requirements that must be met in order to transfer such information, or authorize the release or representation of such information through an agent..."

Most users of the Internet concern themselves with three aspects of the Internet only -- that is, their physical connection (e.g., a computer plus DSL, cable or dial-up), applications (e.g., surfing the web with the help of a web browser), and content (e.g., banking online). As such, the Applications Area deals with one of the layers of the Internet that is not just left to the experts to manage but rather that attracts public attention.

The Applications Area is probably where end users see the IETF's focus on interoperablity most clearly; the ability of multiple email systems to interact, for example, is a clear success of the IETF -- the common message format and global mesh of servers provides a service that most users understand and use.

This area is also, however, where most users can see the IETF's failures in working out the Internet's architecture. For example, the IETF attempted to work out a standard for IM systems, but was not able to get the development community to agree to a single mechanism or format. Since that time, IM use has grown enormously, but folks continue to have to use multiple clients or multiple-system clients to get around the lack of interoperability. The IETF continues to push in this area. The development of CPIM as a standard for 'interchange' between systems, for example, will allow for end-to-end data integrity or encryption, and the development of PIDF for presence will be used both by IM and other systems. But the lack of success in the early effort means interoperability is growing to catch up with the system itself; SIP/SIMPLE and Jabber/XMPP do interoperate and the people involved in the Applications Area hope more will adopt these mechanisms over time.