Re Broadband Test System

Spirent PLC
26 September 2000

                       SPIRENT ANNOUNCES OPTICAL TESTER
         Introduces Industry first for integrated DWDM and ATM/IP Testing


Spirent plc, the international network technology company, announces the
addition of a Layer 1 optical capability to its Adtech AX/4000 Broadband Test
System, creating the industry's first system to support multi layer optical
network testing.  This development, to be launched by Spirent Communications
at the Networld + Interop trade fair in Atlanta, Georgia addresses a critical
concern for developers of optical communications systems, one of the fastest
growing and most significant segments of the communications equipment market.

Nicholas Brookes, Chief Executive of Spirent plc, commented:  'This
comprehensive coverage of optical testing requirements is a very exciting step
forward and demonstrates Spirent's successful internal development of new
technology applications, opening significant new market opportunities.  It
also enhances our strategic objective of supporting customers through a unique
ability to integrate performance analysis across layers and technologies.

This product provides the first industry solution for testing from SONET up
through the routing stack and beyond.  A single platform that addresses Layer
1 through Layer 7 of the OSI stack at these high speeds is absolutely
essential for the manufacturers and service providers that want to develop and
deploy the foundation for the Next Generation Network.'

The new Layer 1 testing functionality will allow powerful transmission
performance analysis of optical cross-connects, optical switches, ADMs and
DWDM systems as well as traditional routers and switches. Layer 1 to 7 testing
with Spirent Communications' Adtech AX/4000 Broadband Test System offers the
world's leading providers of optical networking and routing equipment true
carrier-class reliability, scalability and performance over the Internet and
IP networks.

With the convergence of optical routing functionality, developers of these
systems must evaluate the performance and conformance of their systems at all
layers of the stack.  The Adtech AX/4000 Broadband Test System is the only
system on the market to provide this kind of testing capability on a single,
integrated platform.

According to a study by Frost & Sullivan, there is growing need in the
broadband and next generation network industries for integrating physical
layer testing with other higher layers in the network. This assumes greater
importance with increasing network speeds, such as OC-192c, and with the
advent of proposed technologies that will attempt to reduce framing overheads
between the physical stack and other high level layers in future systems.

'With an increasing level of convergence between layers and resulting inter-
layer dependence, it is our opinion that Layer 1 testing cannot remain
divorced from higher layer testing for long, and that a new market is in the
offing here,' said Shekar Gopalan, Director of Consulting, Frost & Sullivan.
'Spirent Communication's Layer 1 optical network test capability for its
Adtech AX/4000 Broadband Test System fills a critical void in the area of
integrated test platforms. As the first to offer this capability, Spirent has
the ability to build a leadership position in this market space by offering a
one-stop shop for integrated Layer 1 to Layer 7 testing.'

Recent advances in technology are providing for a tighter coupling between the
optical domain and the routing domain.  New emerging standards, such as
MPLambdaS, allow optical bandwidth allocation based on IP differentiated
traffic flows, as well as multiple technology support.  It is no longer
sufficient for optical manufacturers to test solely at Layer 1 and switch/
router manufacturers to test solely at Layers 3 and 4.

'Combined with the Adtech AX/4000's ATM, IP and SONET testing capabilities,
Layer 1 optical testing from Spirent Communications will help drive the
transition from SONET ring to new optical mesh network architectures,' said
Tareq Hoque, President of Spirent Communications' Adtech Systems.  'As a
result, service providers can provision services more quickly and efficiently
and deliver more complex differentiated broadband services to customers at a
fraction of the time and cost.'


Enquiries:

Nicholas Brookes, Chief Executive    Spirent plc           [phone]
Eric Hutchinson, Finance Director
Geoff Zeidler, Director of Business Development

Jon Coles/Rupert Young               Brunswick (London)    [phone]
Sara Strong/Nina Pawlak              Brunswick (New York)  [phone]

Background note:

Spirent plc is an international network technology company providing state-of-
the-art solutions with a focus on high growth, high margin activities. It is a
world leader in advanced telecommunications testing systems and network
products. www.spirent.com

Spirent is quoted on the London Stock Exchange, ticker SPT, and is a FTSE 100
company.  It is classified in the Information Technology Hardware sector.  The
Company operates a Level 1 American Depository Receipt programme (ticker:
SPNUY; CUSIP number: 84856M100).  For information, contact Brian Heston, The
Bank of New York, American Depositary Receipts, 101 Barclay St, 22 West, New
York, NY 10286  Phone: [phone], Fax:  [phone], email:
[e-mail]  web site: www.adrbny.com