Link between several computers in a network setup, or
a connection between two networks which allows messages on one to be routed through to
the other. Gateway functions typically include choreographing of mapping (translation), enveloping or
de-enveloping, logging of transmission
activity, and communications software
functions. c.f. Pass-thru.
Gateway functionality can be accomplished with one gateway that incorporates
all functions listed below, or can be divided into eBusiness gateway and
internet gateway. If divided, then the eBusiness gateway and the internet
gateway need to be able to communicate with each other. A gateway can a
large system running on a number of servers or a small system running on a small
server or workstation connected to a small business or home
The basic components of a gateway are the same whether the
gateway supports traditional EDI, the newer XML standards, or both.
including dictionaries for all supported business content standards
Securitysoftware, including firewalls
and encryption/decryption utilities
Can run to 100,000 Euro.
Need to maintain a repository of digital certificates and signatures for
encryption, authorization and authentication
shield and scanning software
A company may choose to use a
third-party service to perform its gateway functions. This would be
full gateway functionality, and the company's interface to the gateway
would be analogous to connecting the company's iintranet to the company's
own gateway. The host usually requires that special software be
installed on the client. The system requirements vary by
platform and by levels of functionality.
A company may be using one or more
partners' web applications, or logging onto a third-party service provider's
solution to view received documents and create documents to send. For a company using a web application for eBusiness, the equivalent of
the gateway is web browser software. The browser should support
popular scripting languages such as Java.
Gateway Software Packages
The components listed
above may be acquired separately or in one or more packages; it is very common
for all to be included in a single package. Packages without the mapping
software are also common since many large companies prefer to develop or
acquire mapping software or services separately.
If you are considering such a package, verify that it includes an
automatic recovery/restart feature, which would give you the capability to
automatically recover any data being processed during either a power or
communications failure. When integrated with the other gateway software
components, this feature also normally restarts the software component so that
processing can begin at the point at which it was terminated.
Also take into consideration what
connection methods are supported by the software.
Does it support the legacy analog modem connection protocols?
Although the scheduled transmission of EDI and/or XML data is a desirable function,
permitting a user to manually start the communications process is also
useful. Manual control of the communications software facilitates its
initial configuration and aids with correcting communication errors.
There are currently two prevailing
parsing (mapping) methods
being used for XML files, DOM and
SAX. Both have advantages
and disadvantages. Be sure to ask your solution provider which method they
use, in order to determine if it matches your needs.
is "memory resident" or "tree-driven",
which means that the entire XML file being mapped is stored inside the parsing
program, in the form of a tree data structure. The advantage is that the
entire content of the file is available to the parser, so if the processing of
data presented at the beginning of the file depends on a piece of data that is
presented near the end of the file, the parser can handle it - if the file is
not too large. DOM allows more capabilities for data manipulation, since
all of the data in the file is available in memory. The disadvantages
are that DOM can be slow, and there is a limit to the files size that a
DOM-based parser can handle without crashing.
In the RosettaNet PIP3A4 Purchase Order Request, the Tax Exemption Status
occurs toward the end of an instance of a 3A4 Purchase Order, due to the
alphabetical sort of the DTD. If processing of the Account
Description near the beginning of the file depends on the Tax Exemption
Status, and the file is not very large, DOM works because it can hold the
Account Description in memory until it finds Tax Exemption Status and figure
out what to do with it.
is "streaming" or "event-driven".
SAX processes the XML file a few records at at time, detecting the beginning
and end of data elements and processes each bit of data as a parsing event,
then discards that data and moves on to the next bits of data. SAX
is a faster processor than DOM, and, since the entire file doesn't have to be
read into memory, SAX can handle very, very large files, assuming that the
server has enough storage space for input and output files. However, SAX
assumes that all the data in the XML file is sent in the sequence in which it
needs to be processed, so SAX can be problematic if the interpretation of bits
of data depends on data that can't be read into memory until the earlier bits
of data depending have been erased from memory.
Communications Audit Trail
A communications audit trail provides the user with a log detailing the
transmission of each interchange or file. Information typically provided with an
audit trail includes: times, dates, identifiers, acknowledgments, errors
encountered, etc. Audit trails are useful for debugging transmission
problems, generating reports, and verifying that an interchange was sent or
received by a trading partner.
There is a variety of communication data which might need to be viewed by
an gateway user. This information includes scheduled transmissions, audit
trails, outstanding functional acknowledgments, configuration data, and
others. Rather than manually editing files, a gateway product might provide
a utility for viewing various aspects of communications data.
Software Costs - 1997
PC or Mac Front-end, no integration
capability - 1,500 to 3,500 USD
PC or Mac Front-end with import/export
capability - 2,000 to 7,000 USD
Unix Server Platform - 3,500 - 12,000 USD
Minicomputer Platform - 7,000 to 30,000
Mainframe Platform - 20,000 - 90,000 USD
Maintenance - 15-20% per year
80% of EDI-enabled companies in the U.S. use a PC or Mac Front-end solution.