Presents your 
XML E-NEWSLETTER for November 13, 2002

<------------------------------------------->

COMPLETE BUSINESS TRANSACTIONS WITH AS2

Electronic business-to-business (B2B) transactions have been in
existence for some time, thanks to Electronic Data Interchange (EDI) 
technology.
Unfortunately, a combination of cost and complexity has kept many
organizations from adopting EDI technologies for their transactions. 
Some of these organizations today are looking to XML to help solve their B2B
problems. A key component of the XML solution is going to be a 
relatively new technology called AS2.

THE SHELF LIFE OF EDI

EDI technology is notoriously complex and often incurs huge costs for
organizations that implement it. As XML technologies have matured, its
value for B2B transactions has become clear, which may shorten the 
shelf life of EDI. However, XML is still somewhat incomplete when compared 
to the capabilities of EDI.

One key complexity of EDI transactions is the transportation of messages
from one organization to another. With EDI, the transaction is actually
managed by a "middleman" called the Value Added Network (VAN).

A VAN is sort of akin to a logistics company such as UPS or FedEx. They
are responsible for receiving the "package" from one organization and
securely delivering it to another. Just as XML has accentuated the
complexities of the EDI document format, the Internet has accentuated 
the complexities of using a VAN.

THE INTERNET--THE ULTIMATE VAN

Because it's easy for many organizations to get online with Internet
access, the value of the VAN becomes questionable. Why pay the middleman
when you can go direct? Traditionally the answer has been security and
reliability. The Internet is inherently insecure and unreliable on its 
own.

To address this issue the Internet Engineering Task Force (IETF) created
specifications for a new technology called Electronic Data
Interchange-Internet Integration (EDIINT). EDIINT is designed for using 
the Internet as the transport for exchanging EDI information, rather than
a VAN.

There are currently two specifications that define the techniques for
using the Internet to transmit EDI documents. The first specification,
called Applicability Statement 1 (AS1) outlines the technology for using
Simple Mail Transfer Protocol (SMTP) to transmit EDI data. SMTP essentially
provides an e-mail solution for transferring information.

To address issues of synchronous messaging and other problems with SMTP, 
the IETF created a newer specification called AS2, which defines how to
send EDI documents using HTTP--the language of the Web rather than the
language of e-mail.

Traditionally both AS1 and AS2 have been defined and used in terms of
EDI documents; however, with the increasing value and relevance of XML 
to B2B processes, AS2 is actually somewhat broader than just EDI. As a
result, many companies have developed technologies that take advantage 
of XML as the business language and the Internet as the transport using AS2
technology.

HOW IT WORKS

With AS2, messages are packaged as Secure/Multipurpose Internet Mail
Extensions (S/MIME) attachments. S/MIME is similar to MIME, which is an
Internet technology for identifying file types based on a descriptor. 
S/MIME adds security technology, such as encryption, to traditional MIME
messages. The specification also supports the use of HTTPS, which wraps 
the HTTP protocol with an encryption layer.

To facilitate the handling of the messages through HTTP, AS2 specifies
several new header components. Messages are sent to a Web server using 
the HTTP Post method. The actual message (whether EDI or XML) is sent as
multipart/form-data.

The headers of the HTTP Post request may include additional information
about the data such as who sent it, who should receive it, where
disposition notifications should be sent, and any receipt requests. The 
header extensions also support generic user-defined parameters to facilitate
customization of the exchange process.

MORE INFORMATION

The AS2 specification is currently an IETF draft, although many
organizations have implementations available. The draft is viewable on 
the IETF Web site.
http://www.ietf.org/internet-drafts/draft-ietf-ediint-as2-11.txt

Brian Schaffner is a senior consultant for Fujitsu Consulting. He
provides architecture, design, and development support for Fujitsu's 
Telcom360 group.

----------------------------------------