InterCall was founded to create a cost effective, open, robust and scalable host-based software foundation
on which to build Excel based software solutions and to provide prebuilt but open solutions built on this
foundation. By extending Excel's built-in capabilities and developing a robust "operating system" on top of
them, the InterCall Switch Operating System (ISOS) provides a carrier class foundation upon which
applications can be quickly developed and run using commercially available, widely deployed software
tools and standards.

The ISOS provides a working "central office ready" switch with built-in capabilities for administration,
routing, translations and call detail recording "out-of-the-box". Complete signaling and interworking
support for SS7, ISDN, many North American inband, E1R2 and PPL variants are all included. These are
true "configure and run" capabilities are administered via an easy to use user interface. In addition, with the
ISOS application layer and Extensible Call Processing Layer (ECPL), additional feature can easily be
added. Most complex applications can be delivered in less than 2 months. Finally, integrated and open
OAM&P and SNMP solutions that work today provide the means to administer and deploy systems
ranging from a single switch to an international network.

The ISOS offers "a working solution for today and a clear path to tomorrow." Applications written for the
ISOS run on the entire Excel product line from a 16 node EXNET based system down to a single PCX
and everything in between. An application can be written today for a single switch and tomorrow the same
application can be deployed on a multiple node EXNET system with access to all the latest Excel based
innovations. The ISOS provides "a stable and robust software foundation in a world of evolving
standards". InterCall is committed to providing complete and easy to use access and interworking with
every Excel product from the latest Excel hardware to their latest innovations in low level software.

The ISOS and all InterCall products are written in 'C' and 'C++' to give software developers instant
access to the wealth of commercially available solutions. There is no need to learn "yet another proprietary
language" or to be faced with the mystery of developing and debugging an embedded solution in hex. In
addition, since the ISOS is an open solution, third party developed switching applications can be deployed
on the same platform using the ISOS's well defined interfaces. The ISOS provides an application layer as
well as extensive call processing capabilities via the Extensible Call Processing Layer. Finally source code
is available so that the ISOS itself or any of the InterCall products can easily be extended.

InterCall products run on most Unix platforms including SCO Open Server, Unixware, Sun x86 and Sun
SPARC. In its commitment to provide complete support, InterCall will add Windows NT to the list of
supported operating systems in the fourth quarter of 1998.

InterCall provides "The Most Open and Complete Software Solution for the Excel Product Line".

You can reach InterCall Communications & Consulting at www.intercallco.com