UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 6-K REPORT OF FOREIGN PRIVATE ISSUER PURSUANT TO RULE 13a-16 OR 15d-16 UNDER THE SECURITIES EXCHANGE ACT OF 1934 For the month of October, 2006 SPIRENT COMMUNICATIONS plc _____________________________________________________________________ (Translation of registrant's name into English) Spirent House, Crawley Business Quarter, Fleming Way, Crawley, West Sussex RH10 9QL, UK. _____________________________________________________________________ (Address of principal executive offices) Indicate by check mark whether the registrant files or will file annual reports under cover Form 20-F or Form 40-F. Form 20-F X Form 40-F..... Indicate by check mark whether the registrant by furnishing the information contained in this Form is also thereby furnishing the information to the Commission pursuant to Rule 12g3-2(b) under the Securities Exchange Act of 1934. Yes ..... No X If "Yes" is marked, indicate below the file number assigned to the registrant in connection with Rule 12g3-2(b): 82- ________ NOTIFICATION OF TRANSACTIONS OF DIRECTORS, PERSONS DISCHARGING MANAGERIAL RESPONSIBILITY OR CONNECTED PERSONS This form is intended for use by an issuer to make a RIS notification required by DR 3.1.4R(1). (1) An issuer making a notification in respect of a transaction relating to the shares or debentures of the issuer should complete boxes 1 to 16, 23 and 24. (2) An issuer making a notification in respect of a derivative relating to the shares of the issuer should complete boxes 1 to 4, 6, 8, 13, 14, 16, 23 and 24. (3) An issuer making a notification in respect of options granted to a director /person discharging managerial responsibilities should complete boxes 1 to 3 and 17 to 24. (4) An issuer making a notification in respect of a financial instrument relating to the shares of the issuer (other than a debenture) should complete boxes 1 to 4, 6, 8, 9, 11, 13, 14, 16, 23 and 24 Please complete all relevant boxes in block capital letters. 1. Name of the issuer SPIRENT COMMUNICATIONS PLC 2. State whether the notification relates to (i) a transaction notified in accordance with DR 3.1.4R(1)(a); or (ii) DR 3.1.4(R)(1)(b) a disclosure made in accordance with section 324 (as extended by section 328) of the Companies Act 1985; or (iii) both (i) and (ii) (iii) THIS NOTIFICATION IS MADE IN ACCORDANCE WITH BOTH 3. Name of person discharging managerial responsibilities/director ERIC HUTCHINSON 4. State whether notification relates to a person connected with a person discharging managerial responsibilities/director named in 3 and identify the connected person N/A 5. Indicate whether the notification is in respect of a holding of the person referred to in 3 or 4 above or in respect of a non-beneficial interest N/A 6. Description of shares (including class), debentures or derivatives or financial instruments relating to shares SPIRENT COMMUNICATIONS PLC ORDINARY SHARES OF 3&1/3 PENCE 7. Name of registered shareholders(s) and, if more than one, the number of shares held by each of them N/A 8 State the nature of the transaction SALE OF SHARES ARISING FROM THE EXERCISE OF AN OPTION AWARDED UNDER THE SPIRENT1995 EXECUTIVE SHARE OPTION SCHEME 9. Number of shares, debentures or financial instruments relating to shares acquired N/A 10. Percentage of issued class acquired (treasury shares of that class should not be taken into account when calculating percentage) N/A 11. Number of shares, debentures or financial instruments relating to shares disposed 1,128,000 ORDINARY SHARES OF 3&1/3 PENCE 12. Percentage of issued class disposed (treasury shares of that class should not be taken into account when calculating percentage) 0.126% 13. Price per share or value of transaction 59.179 PENCE PER SHARE 14. Date and place of transaction 18 OCTOBER 2006 15. Total holding following notification and total percentage holding following notification (any treasury shares should not be taken into account when calculating percentage) 871,731 SPIRENT COMMUNICATIONS PLC ORDINARY SHARES OF 3&1/3 PENCE (0.097% OF THE ISSUED SHARE CAPITAL EXCLUDING TREASURY SHARES) 16. Date issuer informed of transaction 18 OCTOBER 2006 If a person discharging managerial responsibilities has been granted options by the issuer complete the following boxes 17 Date of grant 25 MARCH 2003 18. Period during which or date on which it can be exercised 25 MARCH 2006 TO 24 MARCH 2013 19. Total amount paid (if any) for grant of the option NIL 20. Description of shares or debentures involved (class and number) 1,128,000 OPTIONS OVER ORDINARY SHARES OF 3 & 1/3 PENCE EACH 21. Exercise price (if fixed at time of grant) or indication that price is to be fixed at the time of exercise 16 PENCE PER SHARE 22. Total number of shares or debentures over which options held following notification 3,494,742 OPTIONS OVER ORDINARY SHARES OF 3 & 1/3 PENCE EACH 23. Any additional information 24. Name of contact and telephone number for queries WARREN NASH Tel: 01293 767676 Name and signature of duly authorised officer of issuer responsible for making notification WARREN NASH Date of notification 19 OCTOBER 2006 Signatures Pursuant to the requirements of the Securities Exchange Act of 1934, the registrant has duly caused this report to be signed on its behalf by the undersigned, thereunto duly authorized. ______MICHAEL ANSCOMBE______ (Registrant) Date: October 19, 2006 By ____/s/ Michael Anscombe____ (Signature)*