Transaction in Own Shares

Spirent Communications PLC
20 September 2006


Spirent Communications Plc
Transaction in Own Shares

Spirent Communications PLC announces that it has today purchased through
Citigroup Global Markets U.K. Equity Limited 800,000 ordinary shares at an
average price of  47.37 pence per share. The highest price and the lowest price
paid for these shares were  47.5 pence and  47.0 pence respectively.

Following the above purchase, Spirent Communications plc holds 63,640,000
Spirent Communications plc ordinary shares in treasury, and has 908,415,762
Spirent Communications plc ordinary shares in issue (excluding treasury shares).


                      This information is provided by RNS
            The company news service from the London Stock Exchange        SURABRNBRKUAR