Soft switches are
poised to replace the call processing functions of the Class 4 and
5 switches previously used by the telecommunications industry.
This new breed of switch is smaller, less expensive, less power
consuming, more reliable, more flexible, and more efficient than
its predecessors. A soft switch can be placed in a closet, whereas
the equivalent Class 5 switch functionality would fill a building
to achieve the same capacity. The proliferation of control
protocols makes soft switches the ideal solution for today’s market.
Because soft switches derive their name from the “soft” in
software, they can support many protocols at once.
By utilizing soft-switch technology along with a media gateway,
a simplified network architecture could be developed (see
Figure 1-12). A single core switching product is needed to support
both voice and data for 2G, 3G, and future all-IP networks.
The support for all three generations of networks is still a
requirement but the interfaces are much simpler.
The solution may be based on state-of-the art, high density,
scalable, soft-switch technology and utilize a multimedia
session initiation protocol (SIP) session manager as the basic
building block for services. This architecture is all-IP ready
and fully compatible with 2G, 2.5G, and 3G voice and data
specifications. It could support present operator needs yet
allow for seamless evolution to future technologies.
A soft-switch/media gateway product developed by Spatial
Wireless in shown in Figure 1-13. This product is designed for
next generation markets—packet-based core switching for the
GSM, CDMA, UMTS and All-IP wireless markets. These elements
enable unique voice/data converged services, help maintain
service transparency across different wireless generations,
and can result in more than 50 percent savings in capital and
operational expenditures. The Spatial’s Portico product is an
overlay gateway product that supports the introduction of
voice, data and converged services.
As we have seen in this overview of the history of modern communications,
competing standards and protocols both drive
and hinder the development of a truly ubiquitous Wireless
Internet. Chapter 2 explores the evolution of these technologies
in greater depth.