ASYNCHRONOUS TRANSFER MODE-USER TO NETWORK INTERFACE
                               (ATM-UNI)

PRODUCT DESCRIPTION:

ATM is unlike any preceding technology and promises to revolutionize
communications worldwide.  The promise of universal interactive
communications is being enabled by ATM transport.

In the field of high speed virtual networking, ATM is a key component.
ATM is a telecommunications concept defined by ANSI and ITU (formerly CCITT)
standards for carriage of a complete range of user traffic, including voice,
data and video signals on any "User to Network Interface" (UNI).  As such,
ATM is extremely well suited to high speed networking in the 1990s.  ATM
technology aggregates user traffic from existing applications onto a single
UNI and facilitates multimedia networking between high speed devices.  These
users' applications include SMDS, frame relay, native LAN access, video, and
voice.

ATM transport refers to the use of ATM switching and multiplexing techniques
(SONET) to convey end-user traffic from source to destination.  ATM's ability to mix
traffic and allow users and applications to share the same facility allows
GTE to provide higher speed transport at reduced prices, in comparison to
today's Time Division Multiplexing technology.  ATM carries user traffic,
voice, video, or data within ATM formatted cells consisting of 53 octets
(5 header and 48 payload).  From 1994 through 1996, ATM will likely require
permanent virtual circuits (PVCs) be used to establish the end-to-end
connection similar to the current Frame Relay Service.

End users will access GTE's ATM network in a variety of ways.  GTE will
provide Access Switches within our central offices and at the customer's
premise(s) that will allow ATM access via native LAN interfaces (token ring,
ethernet, FDDI); video interfaces (JPEG, MPEG); and circuit emulation which
will integrate isochronous traffic (voice, video).  Some may request direct
connection(s) to our ATM network from their ATM CPE switches.  Customers will
also access GTE's ATM network via Intermediate System (IS) such as IP router,
that encapsulates data into ATM cells, or via GTE's SMDS, Frame Relay or
Video Connect service and then forwards the cells across the ATM network.

APPLICATIONS:

ATM applications include the transport of any voice, video or data that
includes any of the current applications similar to the existing TDM network
which supplies transport for these services today.

The ATM switches, in conjunction with GTE's SONET fiber ring network, enable
GTE to deliver today's high-speed data services, as well as emerging
multimedia services to both business and residential customers over the
public switched network.

ATM is a technology that allows GTE to provide high-speed services to our
customers at substantially lower costs.  With ATM, we will be able to
economically offer broadband services such as:

      -     Data Transfer
      -     Interactive Video
      -     Medical Imaging

For more information, call 1-800-483-4926 M-F 8am - 8pm eastern.

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