Washington, D.C. 20549


Filed pursuant to Section 16(a) of the Securities Exchange Act of 1934
or Section 30(h) of the Investment Company Act of 1940
OMB Number: 3235-0104
Estimated average burden
hours per response: 0.5
1. Name and Address of Reporting Person*
Valdivielso Fernando

(Last) (First) (Middle)


(City) (State) (Zip)
2. Date of Event Requiring Statement (Month/Day/Year)
3. Issuer Name and Ticker or Trading Symbol
Ribbon Communications Inc. [ RBBN ]
4. Relationship of Reporting Person(s) to Issuer
(Check all applicable)
Director 10% Owner
X Officer (give title below) Other (specify below)
EVP, Sales - EMEA and APA
5. If Amendment, Date of Original Filed (Month/Day/Year)
6. Individual or Joint/Group Filing (Check Applicable Line)
X Form filed by One Reporting Person
Form filed by More than One Reporting Person
Table I - Non-Derivative Securities Beneficially Owned
1. Title of Security (Instr. 4) 2. Amount of Securities Beneficially Owned (Instr. 4) 3. Ownership Form: Direct (D) or Indirect (I) (Instr. 5) 4. Nature of Indirect Beneficial Ownership (Instr. 5)
Table II - Derivative Securities Beneficially Owned
(e.g., puts, calls, warrants, options, convertible securities)
1. Title of Derivative Security (Instr. 4) 2. Date Exercisable and Expiration Date (Month/Day/Year) 3. Title and Amount of Securities Underlying Derivative Security (Instr. 4) 4. Conversion or Exercise Price of Derivative Security 5. Ownership Form: Direct (D) or Indirect (I) (Instr. 5) 6. Nature of Indirect Beneficial Ownership (Instr. 5)
Date Exercisable Expiration Date Title Amount or Number of Shares
Explanation of Responses:
No securities are beneficially owned.
Justin Ferguson, Attorney-in-Fact 05/07/2020
** Signature of Reporting Person Date
Reminder: Report on a separate line for each class of securities beneficially owned directly or indirectly.
* If the form is filed by more than one reporting person, see Instruction 5 (b)(v).
** Intentional misstatements or omissions of facts constitute Federal Criminal Violations See 18 U.S.C. 1001 and 15 U.S.C. 78ff(a).
Note: File three copies of this Form, one of which must be manually signed. If space is insufficient, see Instruction 6 for procedure.
Persons who respond to the collection of information contained in this form are not required to respond unless the form displays a currently valid OMB Number.
                                                                 EXHIBIT 24

                             POWER OF ATTORNEY

      Know all by these presents, that the undersigned hereby constitutes

and appoints Justin Ferguson the undersigned's true and lawful

attorney-in-fact to:

(1) prepare, execute in the undersigned's name and on the undersigned's

behalf, and submit to the U.S. Securities and Exchange Commission (the "SEC")

a Form ID, including amendments thereto, and any other documents necessary

or appropriate to obtain codes and passwords enabling the undersigned to

make electronic filings with the SEC of reports required by Section 16(a) of

the Securities Exchange Act of 1934 (the "Act") or any rule or regulation

of the SEC;

(2) execute for and on behalf of the undersigned, in the undersigned's

capacity as an officer and/or director of Ribbon Communications Inc. (the

"Company"), Forms 3, 4, and 5 in accordance with Section 16(a) of the Act

and the rules thereunder, and any other forms or reports the undersigned may

be required to file in connection with the undersigned's ownership,

acquisition, or disposition of securities of the Company;

(3) do and perform any and all acts for and on behalf of the undersigned

which may be necessary or desirable to complete and execute any such Form 3,

4, or 5, or other form or report, and timely file such form or report with

the SEC and any stock exchange or similar authority; and

(4) take any other action of any type whatsoever in connection with the

foregoing which, in the opinion of such attorney-in-fact, may be of benefit

to, in the best interest of, or legally required by, the undersigned, it

being understood that the documents executed by such attorney-in-fact on

behalf of the undersigned pursuant to this Power of Attorney shall be in

such form and shall contain such terms and conditions as such attorney-in-

fact may approve in such attorney-in-fact's discretion.

      The undersigned hereby grants to such attorney-in-fact full power and

authority to do and perform any and every act and thing whatsoever requisite,

necessary, or proper to be done in the exercise of any of the rights and

powers herein granted, as fully to all intents and purposes as the under-

signed might or could do if personally present, with full power of subst-

itution or revocation, hereby ratifying and confirming all that such

attorney-in-fact, or such attorney-in-fact's substitute or substitutes,

shall lawfully do or cause to be done by virtue of this power of attorney

and the rights and powers herein granted. The undersigned acknowledges that

the foregoing attorney-in-fact, in serving in such capacity at the request

of the undersigned, is not assuming, nor is the Company assuming, any of

the undersigned's responsibilities to comply with Section 16 of the Act.

This Power of Attorney shall remain in full force and effect until the

undersigned is no longer required to file Forms 3, 4, and 5 with respect

to the undersigned's holdings of and transactions in securities issued by

the Company, unless earlier revoked by the undersigned in a signed writing

delivered to the foregoing attorneys-in-fact.

      IN WITNESS WHEREOF, the undersigned has caused this Power of Attorney

to be executed as of this 5th day of May, 2020.

/s/ Fernando Valdivielso


Fernando Valdivielso