The Case for Virtual Business Processes
thieves, in a virtual business, you do not place all your data on display for all your
competitors to review.
The trick is to apply technology in such a way that the ideas of access and data
security can be applied quickly and easily. You can limit the space that needs to be
secured in two ways:
Implement virtual LAN (VLAN) technology.
Build a portal through which users must pass to access your business.
The following sections examine each of these approaches in more detail.
This section assumes that you are familiar with LAN technology. VLANs
push the physical limits by extending the concept of locality.
LAN technology was invented to connect resources in a local environment to
achieve interconnection of workers to share files, applications, and devices such
as printers. This works fine when the environment to be interconnected is rather
small or when it is mapped over a fairly small geography. Problems arise,
however, when the number of users increases to more than a few hundred or when
the environment over which services will be delivered encompasses large
geographic areas.
The problem is with the Ethernet technology that is commonly used in the
local environment. Ethernet is based on the carrier sense multiple access
collision detect (CSMA/CD) protocol. In this protocol, the equivalent of a
digital mob scene is refereed according to who can yell when no one else is
yelling. Everyone else quiets down and lets the yeller yell until he runs out of
breath. Then someone else yells. But what if there are so many people trying to
yell that there is hardly any quiet space? Or, just as bad, what if the distance
between two people yelling is so great that neither side can hear the other one
yelling? Figure 5-3 illustrates this process: Everyone is on the same line, talking
at once.
These problems occur only when the yelling parties are in the same logical
environment. If technology is applied to subdivide the environment into smaller
Chapter 5: Capitalizing on a Virtual Presence
chunks, these situations are mitigated. In practice, this is accomplished by placing
routers or intelligent hubs or switches in the network architecture.
Figure 5-3 The Problem with LANs
By inserting devices designed to subnet the networked environment, you can
segregate serving areas so that smaller groups contend for yelling space and so that
geographically separated groups or individuals don’t have to wait for the echo of
distant yellers to talk.
The beauty of a subnetting device is that, although a LAN is on one side, any
kind of network can be on the other side. As far as the local participants are
concerned, the device is a singular instance representing all the other possible
participants in the local environment. The subnetting device talks to any other
subnetting device, separated sometimes by extremely long distances. The local
devices and users are unaware of the device’s location. Figure 5-4 illustrates how
subnetting allows you to segregate the load so that fewer users are contending for
the same line.
This concept of switching between subnets or LANs not only solves the
problem of contention on Ethernet-based networks but also provides a means of
extending the network to any location that is connected to the switch. When
combined with access control, so that only authorized entities can access the
switch from the far side, the virtual business has a way of extending its network to
employees as well as business partners, suppliers, and customers. The application
of VLAN technology is called an intranet when used within the company and an
extranet when connecting the supply chain or business partners.


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