UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

Washington, D.C. 20549

SCHEDULE 13D

Under the Securities Exchange Act of 1934

Radvision Ltd.

(Name of Issuer)

Ordinary Shares, nominal value NIS 0.10 per share

(Title of Class of Securities)

M81869105

(CUSIP Number)

Pamela F. Craven, Esq.

Chief Administrative Officer

Avaya Holdings Corp.

211 Mount Airy Road

Basking Ridge, New Jersey 07920

(908) 953-6000

with copies to:

Irving L. Rotter

Asi Kirmayer

Sidley Austin LLP

787 Seventh Avenue

New York, NY 10019

(212) 839-5300

(Name, Address and Telephone Number of Person Authorized to Receive Notices and Communications)

March 14, 2012

(Date of Event which Requires Filing of this Statement)

If the filing person has previously filed a statement on Schedule 13G to report the acquisition that is the subject of this Schedule 13D, and is filing this schedule because of §§ 240.13d-1(e), 240.13d-1(f) or 240.13d-1(g), check the following box.  ¨

The information required on the remainder of this cover page shall not be deemed to be “filed” for the purpose of Section 18 of the Securities Exchange Act of 1934 (“Act”) or otherwise subject to the liabilities of that section of the Act but shall be subject to all other provisions of the Act (however, see the Notes).

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Item 1. Security and Issuer

This Schedule 13D relates to the Ordinary Shares, nominal value ten Israeli Agorot (NIS 0.10) per share (the “Shares”), of Radvision Ltd., an Israeli corporation (the “Issuer”). The principal executive office of the Issuer is 24 Raoul Wallenberg Street, Tel Aviv 69719, Israel.

Item 2. Identity and Background

This Schedule 13D is being filed jointly by Avaya Inc. (“Parent”), Avaya Holdings Corp. (“Avaya Holdings”, and together with Parent, the “Avaya Reporting Persons”), Silver Lake Partners II, L.P. (“SLP II”), Silver Lake Partners III, L.P. (“SLP III”), Silver Lake Technology Investors II, L.P. (“SLTI II”), Silver Lake Technology Investors III, L.P. (“SLTI III”, and together with SLP II, SLP III and SLTI II, the “Silver Lake Funds”), Silver Lake Technology Associates II, L.L.C. (“SLTA II”), Silver Lake Technology Associates III, L.P. (“SLTA III”), SLTA III (GP), L.L.C. (“SLTA III GP”) and Silver Lake Group, L.L.C. (“SLG”, and together with the Silver Lake Funds, SLTA II, SLTA III and SLTA III GP, the “Silver Lake Reporting Persons”), Sierra Co-Invest, LLC (“Sierra Co-Invest”), Sierra Co-Invest II, LLC (“Sierra Co-Invest II” and, together with Sierra Co-Invest, the “Co-Invest Entities”) and Sierra Manager Co-Invest, LLC (“Sierra Manager”, and together with the Co-Invest Entities, the “Co-Invest Reporting Persons”), TPG Group Holdings (SBS) Advisors, Inc., a Delaware corporation (“TPG Group Advisors”), David Bonderman and James G. Coulter (Messrs. Bonderman and Coulter and Group Advisors, collectively, the “TPG Reporting Persons”). The Avaya Reporting Persons, the Silver Lake Reporting Persons, the Co-Invest Reporting Persons and the TPG Reporting Persons are hereinafter referred to as the “Reporting Persons”. The agreement among the Reporting Persons to file this Schedule 13D jointly in accordance with Rule 13d–1(k) of the Securities Exchange Act of 1934, as amended (the “Exchange Act”), is attached hereto as Exhibit 99.1.

The Avaya Reporting Persons

Avaya Holdings, together with its subsidiaries, is a leading global provider of next-generation business collaboration and communications solutions that bring people together with the right information at the right time in the right context, enabling business users to improve their efficiency and quickly solve critical business challenges. Parent is a wholly owned subsidiary of Avaya Holdings and is its principal operating subsidiary. Each of Avaya Holdings and Parent are Delaware corporations. The address of their principal place of business and principal office is 211 Mount Airy Road, Basking Ridge, New Jersey 07920. The name, business address and present principal occupation or employment of each executive officer and director of the Avaya Reporting Persons, and the name, principal place of business and address of any corporation or other organization in which such employment is conducted, are set forth on Schedule A hereto and incorporated herein by reference.

As of the date hereof, the Silver Lake Reporting Persons and the TPG Reporting Persons collectively beneficially own approximately 99% of the equity interests in Avaya Holdings.

During the last five years, none of the Avaya Reporting Persons and, to the knowledge of the Avaya Reporting Persons, no person named on Schedule A (the persons so named, the “Avaya Individuals”), has been convicted in a criminal proceeding (excluding traffic violations or similar misdemeanors).

During the last five years, none of the Avaya Reporting Persons and, to the Avaya Reporting Persons’ knowledge, no Avaya Individual (with the exception of Kevin B. Rollins (“Mr. Rollins”), as discussed below), was a party to a civil proceeding of a judicial or administrative body of competent jurisdiction and as a result of such proceeding was or is subject to a judgment, decree or final order enjoining future violations of, or prohibiting or mandating activities subject to, federal or state securities laws or finding any violation with respect to such laws.

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On July 22, 2010, the Securities and Exchange Commission (the “SEC”) filed a civil injunctive action involving Dell Inc. (“Dell”), which included allegations against Dell and certain of its senior officers, including Mr. Rollins, concerning the failure to provide adequate disclosure in its SEC filings with respect to Dell’s commercial relationship with Intel Corp. Dell and the relevant officers, including Mr. Rollins, agreed, without admitting or denying the allegations, to settle the matter, and the U.S. District Court for the District of Columbia approved such settlement on October 13, 2010. Mr. Rollins’ settlement included a monetary penalty and a permanent injunction prohibiting violations of Sections 17(a)(2) & (3) of the Securities Act of 1933, as amended, and violations, including aiding and abetting violations, of Section 13(a) of the Exchange Act.

The Silver Lake Reporting Persons

Each of the Silver Lake Funds is a Delaware limited partnership whose principal business is investing in securities. SLTA II is a Delaware limited liability company, whose principal business is serving as the general partner of SLP II and SLTI II. SLTA III is a Delaware limited partnership whose principal business is serving as the general partner of SLP III and SLTI III and certain related investment vehicles. SLTA III GP is a Delaware limited liability company whose principal business is serving as the general partner of SLTA III and certain related investment vehicles. SLG is a Delaware limited liability company whose principal business is serving as the sole member of SLTA GP and other investment vehicles.

The principal office for each of the Silver Lake Entities is 2775 Sand Hill Road, Suite 100, Menlo Park, California 94025. SLG is controlled by Michael Bingle, James Davidson, Egon Durban, Kenneth Hao, Glenn Hutchins, Greg Mondre and David Roux (collectively, the “Silver Lake Individuals”). Each of the Silver Lake Individuals is a United States citizen, except Mr. Durban who is a German citizen. The present principal occupation of each of the Silver Lake Individuals is serving in such capacity with respect to SLG and in a similar capacity with affiliates of such Reporting Persons. Each of the Silver Lake individuals disclaims beneficial ownership of the shares held by the Silver Lake Funds and the shares held by the Sierra Co-Invest Entities except to the extent of their pecuniary interest therein.

The principal office of each of James Davidson, Egon Durban and Kenneth Hao is located at c/o Silver Lake, 2775 Sand Hill Road, Suite 100, Menlo Park, California 94025. The principal office of Michael Bingle, Glenn Hutchins, Greg Mondre and David Roux is located at c/o Silver Lake, 9 West 57th Street, 32nd Floor, New York, New York 10019.

During the last five years, none of the Silver Lake Reporting Persons and, to the knowledge of the Silver Lake Reporting Persons, no Silver Lake Individual, has been convicted in a criminal proceeding (excluding traffic violations or similar misdemeanors).

During the last five years, none of the Silver Lake Reporting Persons and, to the knowledge of the Silver Lake Reporting Persons, no Silver Lake Individual, was a party to a civil proceeding of a judicial or administrative body of competent jurisdiction and as a result of such proceeding was or is subject to a judgment, decree or final order enjoining future violations of, or prohibiting or mandating activities subject to, federal or state securities laws or finding any violation with respect to such laws.

The Silver Lake Reporting Persons, the Co-Invest Reporting Persons and the TPG Reporting Persons may be deemed to be a “group” pursuant to Rule 13d–5(b)(1) of the Exchange Act. The Silver Lake Reporting Persons do not expressly affirm membership in a group with the Co-Invest Reporting Persons and the TPG Reporting Persons, and disclaim beneficial ownership of any Shares held by the Co-Invest Reporting Persons and the TPG Reporting Persons, the Avaya Reporting Persons or the Shareholders (as

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defined below). Neither the filing of this Schedule 13D nor any of its contents shall be deemed to constitute an admission that the Silver Lake Reporting Persons or any of their respective affiliates are the beneficial owners of any Shares beneficially owned by the Co-Invest Reporting Persons, the TPG Reporting Persons, the Avaya Reporting Persons or the Shareholders (as defined below) for purposes of Section 13(d) of the Exchange Act, the rules promulgated thereunder or for any other purpose.

The Co-Invest Reporting Persons

Sierra Manager, a Delaware limited liability company is the managing member of each of (i) Sierra Co-Invest, a Delaware limited liability company, and (ii) Sierra Co-Invest II, a Delaware limited liability company, which directly hold shares of common stock and warrants, respectively, of Avaya Holdings. Pursuant to Sierra Manager’s limited liability company operating agreement, each of TPG GenPar (as defined below) and SLTA III has the right to designate one of the two members of Sierra Manager’s management committee. Greg Mondre currently serves as SLTA III’s designee and Eugene Frantz currently serves as TPG GenPar’s designee. The principal office for each of the Co-Invest Entities is 301 Commerce Street, Suite 3300, Fort Worth, TX 76102. The principal office of Sierra Manager is 9 West 57th Street, 32nd Floor, New York, NY 10019.

During the last five years, none of the Co-Invest Reporting Persons has been convicted in a criminal proceeding (excluding traffic violations or similar misdemeanors).

During the last five years, none of the Co-Invest Reporting Persons was a party to a civil proceeding of a judicial or administrative body of competent jurisdiction and as a result of such proceeding was or is subject to a judgment, decree or final order enjoining future violations of, or prohibiting or mandating activities subject to, federal or state securities laws or finding any violation with respect to such laws.

The Co-Invest Reporting Persons, the Silver Lake Reporting Persons and the TPG Reporting Persons may be deemed to be a “group” pursuant to Rule 13d–5(b)(1) of the Exchange Act. Co-Invest Reporting Persons do not expressly affirm membership in a group with the Silver Lake Reporting Persons and the TPG Reporting Persons, and disclaim beneficial ownership of any Shares held by the Silver Lake Reporting Persons, the TPG Reporting Persons, the Avaya Reporting Persons or the Shareholders (as defined below). Neither the filing of this Schedule 13D nor any of its contents shall be deemed to constitute an admission that the Co-Invest Reporting Persons or any of their respective affiliates are the beneficial owners of any Shares beneficially owned by the Silver Lake Reporting Persons, TPG Reporting Persons, the Avaya Reporting Persons or the Shareholders (as defined below) for purposes of Section 13(d) of the Exchange Act, the rules promulgated thereunder or for any other purpose.

The TPG Reporting Persons

TPG Group Advisors is the general partner of TPG Group Holdings (SBS), L.P., a Delaware limited partnership, which is the sole member of TPG Holdings I-A, LLC, a Delaware limited liability company, which is the general partner of TPG Holdings I, L.P., a Delaware limited partnership, which is the sole member of TPG GenPar V Advisors, LLC, a Delaware limited liability company, which is the general partner of TPG GenPar V, L.P., a Delaware limited partnership (“TPG GenPar”), which is the general partner of each of (i) TPG Partners V, L.P., a Delaware limited partnership (“TPG Partners V”), (ii) TPG FOF V-A, L.P., a Delaware limited partnership (“TPG FOF A”), and (iii) TPG FOF V-B, L.P. a Delaware limited partnership (“TPG FOF B” and, together with TPG Partners V and TPG FOF A, the “TPG Funds”). The TPG Funds collectively hold shares of common stock, preferred stock and warrants of Avaya Holdings. Because of the relationship between TPG Group Advisors and the TPG Funds and the Co-Invest Entities, TPG Group Advisors may be deemed to beneficially own the shares of common stock, preferred stock and warrants of Avaya Holdings held by the TPG Funds and the Co-Invest Entities. Messrs. Bonderman and Coulter are the directors, officers and sole stockholders of TPG Group Advisors and may therefore be deemed to beneficially own the shares of common stock, preferred stock and

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warrants of Avaya Holdings held by the TPG Funds and the Co-Invest Entities. Messrs. Bonderman and Coulter disclaim beneficial ownership of the shares of common stock, preferred stock and warrants of Avaya Holdings held by the TPG Funds and the Co-Invest Entities except to the extent of their pecuniary interest therein. The business address of each of the TPG Reporting Persons is c/o TPG Global, LLC, 301 Commerce Street, Suite 3300, Fort Worth, Texas 76102.

The principal business of TPG Group Advisors is serving as the sole ultimate general partner, managing member or similar entity of related entities (including the TPG Funds) engaged in making or recommending investments in securities of public and private companies.

The present principal occupation of David Bonderman is Chairman of the Board and President of Group Advisors and officer, director or manager other affiliated entities.

The present principal occupation of James G. Coulter is director and Senior Vice President of Group Advisors and officer, director or manager of other affiliated entities.

The name, residence or business address, and present principal occupation or employment of each director, executive officer and controlling person of TPG Group Advisors are listed on Schedule B (together with Eugene Frantz, the “TPG Individuals”).

Each of David Bonderman, James G. Coulter and the TPG Individuals is a United States citizen.

During the last five years, none of the TPG Reporting Persons and, to the knowledge of the TPG Reporting Persons, no TPG Individual, (i) has been convicted in a criminal proceeding (excluding traffic violations or similar misdemeanors) or (ii) was a party to a civil proceeding of a judicial or administrative body of competent jurisdiction and as a result of such proceeding was or is subject to a judgment, decree or final order enjoining future violations of, or prohibiting or mandating activities subject to, federal or state securities laws or finding any violation with respect to such laws.

The TPG Reporting Persons, the Co-Invest Reporting Persons and the Silver Lake Reporting Persons may be deemed to be a “group” pursuant to Rule 13d–5(b)(1) of the Exchange Act. The TPG Reporting Persons do not expressly affirm membership in a group with the Co-Invest Reporting Persons and the Silver Lake Reporting Persons, and disclaim beneficial ownership of any Shares held by the Co-Invest Reporting Persons, the Silver Lake Reporting Persons, the Avaya Reporting Persons or the Shareholders (as defined below). Neither the filing of this Schedule 13D nor any of its contents shall be deemed to constitute an admission that the TPG Reporting Persons or any of their respective affiliates are the beneficial owners of any Shares beneficially owned by the Co-Invest Reporting Persons, the Silver Lake Reporting Persons, the Avaya Reporting Persons or the Shareholders (as defined below) for purposes of Section 13(d) of the Exchange Act, the rules promulgated thereunder or for any other purpose.

Item 3. Source and Amount of Funds or Other Consideration

The information set forth in Item 4 is hereby incorporated herein by reference.

As an inducement for Parent to enter into the Merger Agreement (as defined in Item 4 below), on March 14, 2012, concurrently with the execution of the Merger Agreement, each of Zohar Zisapel, Yehuda Zisapel, Boaz Raviv, RAD Data Communications Ltd., RADbit Ltd., Lomsha Ltd. and Michael and Klil Holdings (93) Ltd. (collectively, the “Shareholders”) entered into voting agreements in substantially the same form (collectively, the “Voting Agreements”) with Parent with respect to 6,754,602 Shares beneficially owned, in the aggregate, by the Shareholders, as well as any other Shares acquired by each such Shareholder after the date of the Voting Agreements or as to which any such Shareholder is or

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becomes the beneficial owner or is otherwise able to direct the voting (the “Voting Shares”). Pursuant to the Voting Agreements, each Shareholder agreed, among other things, to vote such Shareholder’s Voting Shares in favor of approving the Merger Agreement and the transactions contemplated by the Merger Agreement, including, but not limited to, the Merger (as defined in Item 4 below). The Voting Shares include 556,548 Shares subject to options that are exercisable within 60 days, which Shares may or may not be exercised by the Shareholders prior to a vote on the Merger Agreement and the other transactions contemplated by the Merger Agreement. As described in response to Item 4, the Voting Shares to which this Schedule 13D relates have not been purchased by the Reporting Persons, and thus no funds were used by the Reporting Persons for such purpose.

The information set forth in response to this Item 3 is qualified in its entirety by reference to the Voting Agreements, copies of which are filed herewith as Exhibits 99.2, 99.3, 99.4, 99.5, 99.6, 99.7 and 99.8 and are hereby incorporated herein by reference.

Item 4. Purpose of Transaction

As an inducement for Parent to enter into the Merger Agreement (as defined below), the Shareholders entered into the Voting Agreements. The purpose of the Voting Agreements is to facilitate the transactions contemplated by the Merger Agreement.

The Issuer, Parent and Sonic Acquisition Ltd. (“Merger Sub”) have entered into a merger agreement, dated as of March 14, 2012 (the “Merger Agreement”), a copy of which is filed herewith as Exhibit 99.9 whereby Merger Sub will merge with and into the Issuer (the “Merger”) on the terms and subject to the conditions set forth in the Merger Agreement and in accordance with the provisions of Sections 314-327 of the Companies Law 5759-1999 of the State of Israel. Pursuant to the Merger, upon closing Merger Sub will cease to exist, the Issuer will become an indirect wholly-owned subsidiary of Parent and each issued Share not owned by Parent, Merger Sub or the Issuer will be converted into the right to receive $11.85 per Share in cash. If the Merger is consummated as planned, the Reporting Persons anticipate that the Issuer will become controlled by the Reporting Persons and Parent and that the Reporting Persons will seek to cause the Shares to be delisted from the NASDAQ Stock Market and the Tel Aviv Stock Exchange and de-registered under the Exchange Act.

Upon consummation of the Merger, the directors of Merger Sub immediately prior to the effective time of the Merger shall be the directors of the surviving corporation until the earlier of their resignation or removal or until their respective successors are duly elected and qualified, as the case may be, in accordance with the surviving corporation’s articles of association. Upon consummation of the Merger, the officers of the Issuer immediately before the effective time of the Merger will be the officers of the surviving corporation, until the earlier of their resignation or removal or until their respective successors are duly elected or appointed and qualified, as the case may be.

The consummation of the Merger is subject to various conditions, including, but not limited to, (i) the representations and warranties with respect to certain matters (including with respect to organization, standing and power of the Issuer and its subsidiaries, share capital of the Issuer and the Issuer’s subsidiaries, and authority, execution, delivery and enforceability of the Merger Agreement) being true and correct as of the closing date of the merger without any exceptions for materiality, certain other representations and warranties (including representations with respect to taxes and extensive representations with respect to intellectual property) being true and correct as of the closing date of the Merger in all material respects and the remaining representations and warranties being true and correct as of the closing date of the merger, subject to other materiality exceptions, (ii) performance by the Issuer, Parent and Merger Sub with their respective obligations under the Merger Agreement (ii) receipt of certain regulatory approvals (including approval of the Office of the Chief Scientist of the Israeli Ministry

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of Trade & Labor) as set forth in the Merger Agreement, (iii) approval of the Merger by the Issuer’s shareholders, (iv) the absence of a material adverse effect with respect to the Issuer and (v) certain other customary conditions. The Merger Agreement may be terminated by the Issuer or the Parent under certain circumstances. For additional details on these conditions and rights of termination, reference is made to the Merger Agreement.

As an inducement to Parent to enter into the Merger Agreement, each of the Shareholders entered into a Voting Agreement with Parent and Merger Sub. Pursuant to the Voting Agreements, the Shareholders agreed, subject to certain exceptions, that at any meeting of the shareholders of the Issuer however called (or any action by written consent in lieu of a meeting) or any adjournment thereof (collectively, a “Meeting”), the Shareholders will vote all Voting Shares (or cause them to be voted) or (as appropriate) execute written consents in respect thereof, (i) in favor of the approval of the Merger Agreement and the approval of the Transactions (as defined in the Merger Agreement), (ii) against any action or agreement (including, without limitation, any amendment of any agreement) that would result in a breach of any representation, warranty, covenant, agreement or other obligation of the Issuer in the Merger Agreement or any of the Ancillary Agreements (as defined in the Merger Agreement), (iii) against any Company Takeover Proposal (as defined in the Merger Agreement) and (iv) against any agreement (including, without limitation, any amendment of any agreement), amendment of the charter of the Issuer or other action that is intended or could reasonably be expected to prevent, impede, interfere with, delay, postpone or discourage the consummation of the Merger and/or the other Transactions (as defined in the Merger Agreement). The Voting Agreements also include (i) a proxy in favor of designees of Parent permitting such designees to vote the Voting Shares in accordance with the foregoing, and (ii) a prohibition on transfers by the Shareholder of Voting Shares until the termination of the Voting Agreement.

The Reporting Persons are not paying any additional compensation to the Shareholders in connection with the execution and delivery of the Voting Agreements.

As a further inducement for Parent to enter into the Merger Agreement, Zohar Zisapel entered into a Non-Competition and Non-Solicitation Agreement, a copy of which is filed herewith as Exhibit 99.10 (the “Non-Competition and Non-Solicitation Agreement”).

The information set forth in response to this Item 4, including, without limitation, the foregoing summary of certain provisions of the Merger Agreement and Voting Agreements, is qualified in its entirety by reference to the Merger Agreement and the Voting Agreements, copies of which are filed herewith as Exhibits 99.9, 99.2, 99.3, 99.4, 99.5, 99.6, 99.7 and 99.8 hereto, respectively, and are hereby incorporated herein by reference.

Item 5. Interest in Securities of the Issuer

The information set forth or incorporated in Items 2, 3, 4 and 6 is hereby incorporated herein by reference.

The following disclosure assumes that there are 19,032,047 Shares outstanding, which is the sum of (i) the number of Shares the Issuer represented in the Merger Agreement was the number of outstanding Shares as of March 11, 2012 and (ii) the number of Shares for which the Shareholders have options exercisable within 60 days of the date hereof. The following disclosure further assumes that the Shareholders beneficially own 6,754,602 Shares, which is the aggregate number of Shares represented in the Voting Agreements as being beneficially owned by the Shareholders, collectively, as of March 14, 2012.

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(a) Pursuant to the Voting Agreements, the Reporting Persons may be deemed for purposes of Rule 13d-3 promulgated under the Exchange Act to beneficially own 6,754,602 Shares, representing for purposes of Rule 13d-3 approximately 35.49% of the outstanding Shares of the Issuer. Except to the extent the reporting Persons may be deemed to have beneficial ownership as a result of the Voting Agreements, the Reporting Persons disclaim any beneficial ownership of such shares, and nothing herein shall be deemed to be an admission by the Reporting Persons as to the beneficial ownership of such Shares.

To the knowledge of the Reporting Persons, none of the Avaya Individuals, the TPG Individuals or the Silver Lake Individuals (collectively, the “Named Individuals”) beneficially own any Shares.

(b) The Reporting Persons may be deemed in certain circumstances, as more fully described in Item 4, to have shared voting power of the 6,754,602 shares beneficially owned by the Shareholders. Except to the extent that they may be deemed to have any such power by virtue of the Voting Agreements, the Reporting Persons do not, and to the knowledge of the Reporting Persons, the Named Individuals do not, have sole power to vote or direct the vote, shared power to vote or direct the vote, or the sole or shared power to dispose or to direct the disposition of any of the Shares.

(c) Except for the execution and delivery of the Voting Agreements and Merger Agreement, none of the Reporting Persons, and to the knowledge of the Reporting Persons, none of the Named Individuals, has effected any transaction in the Shares during the past 60 days.

(d) Not applicable.

(e) Not applicable.

Item 6. Contracts, Arrangements, Understandings or Relationships with Respect to Securities of the Issuer

The information set forth or incorporated in Items 3 and 4 is hereby incorporated herein by reference.

Except for the Merger Agreement, the Voting Agreements and the Non-Competition and Non-Solicitation Agreement described above, to the knowledge of the Reporting Persons, there are no contracts, arrangements, understandings or relationships (legal or otherwise), including, but not limited to, transfer or voting of any of the securities, finder’s fees, joint ventures, loan or option arrangements, puts or calls, guarantees of profits, division of profits or loss, or the giving or withholding of proxies, among the persons named in Item 2 or between such persons and any other person, with respect to any securities of Issuer, including, but not limited to, any securities pledged or otherwise subject to a contingency the occurrence of which would give another person voting power or investment power over such securities.

Item 7. Material to Be Filed as Exhibits

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After reasonable inquiry and to the best of my knowledge and belief, I certify that the information set forth in this statement is true, complete and correct.

Date: March 15, 2012

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SCHEDULE A

EXECUTIVE OFFICERS AND DIRECTORS OF THE AVAYA REPORTING PERSONS

AVAYA HOLDINGS CORP.

Directors

Executive Officers

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AVAYA INC.

Directors

Executive Officers

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SCHEDULE B

DIRECTORS, EXECUTIVE OFFICERS AND CONTROLLING PERSONS OF TPG GROUP ADVISORS

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Exhibit 99.1

AGREEMENT OF JOINT FILING

This joint filing agreement (this “Agreement”) is made and entered into as of this 15th day of March 2012, by and among Avaya Inc., Avaya Holdings Corp., Silver Lake Partners II, L.P., Silver Lake Partners III, L.P., Silver Lake Technology Investors II, L.P., Silver Lake Technology Investors III, L.P., Silver Lake Technology Associates II, L.L.C., Silver Lake Technology Associates III, L.P., SLTA III (GP), L.L.C., Silver Lake Group, L.L.C., Sierra Co-Invest, LLC, Sierra Co-Invest II, LLC and Sierra Manager Co-Invest, LLC, TPG Group Holdings (SBS) Advisors, Inc., David Bonderman and James G. Coulter.

The parties to this Agreement hereby agree to prepare jointly and file timely (and otherwise to deliver as appropriate) all filings on any Schedule 13D and any and all amendments thereto and any other document relating thereto (collectively, the “Filings”) required to be filed by them pursuant to the Securities Exchange Act of 1934, as amended. Each party to this Agreement further agrees and covenants to the other parties that it will fully cooperate with such other parties in the preparation and timely filing (and other delivery) of all such Filings. This agreement may be executed in any number of counterparts, each of which shall be deemed to be an original, but all of which together shall constitute one and the same instrument.

IN WITNESS WHEREOF, the parties hereto have executed this Agreement as of the date first set forth above.

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Exhibit 99.2

VOTING AND SUPPORT AGREEMENT

VOTING AND SUPPORT AGREEMENT (this “Agreement”), dated as of March 14, 2012, by and between Avaya Inc., a Delaware corporation (“Parent”), and the undersigned Shareholder (the “Shareholder”) of Radvision Ltd., a corporation incorporated under the laws of the State of Israel (the “Company”).

WHEREAS, concurrently with the execution of this Agreement, the Company, Parent and Sonic Acquisition Ltd. (“Merger Sub”) are entering into a Merger Agreement as of the date hereof (such Merger Agreement, as it may be amended from time to time, the “Merger Agreement”);

WHEREAS, capitalized terms used but not defined in this Agreement have the meanings ascribed to them in the Merger Agreement;

WHEREAS, as of the date hereof, the Shareholder is the beneficial owner of 5,043,317 Company Ordinary Shares (all such Company Ordinary Shares, together with any other Company Ordinary Shares acquired by the Shareholder after the date hereof or as to which the Shareholder is or becomes the beneficial owner or is otherwise able to direct the voting thereof (including as a result of the exercise of Shareholder Options), being collectively referred to herein as the “Shareholder Shares”) and is the record and beneficial owner of Company Stock Options to purchase an additional 85,000 Company Ordinary Shares (the “Shareholder Options”);

WHEREAS, as a condition to their willingness to enter into the Merger Agreement, Parent and Merger Sub have required that the Shareholder enter into this Agreement; and

WHEREAS, in order to induce Parent and Merger Sub to enter into the Merger Agreement, the Company asked the Shareholder to enter into this Agreement with Parent and Merger Sub, and the Shareholder has agreed and is willing to enter into this Agreement.

NOW, THEREFORE, in consideration of the foregoing and the mutual covenants and agreements contained herein, the parties hereto, intending to be legally bound hereby, agree as follows:

1. Agreements of the Shareholder.

(a) Voting. From the date hereof until any termination of this Agreement in accordance with its terms, at any meeting of the shareholders of the Company however called (or any action by written consent in lieu of a meeting) or any adjournment thereof (a “Meeting”), the Shareholder shall vote all the Shareholder Shares (or cause them to be voted) or (as appropriate) execute written consents in respect thereof, (i) in favor of the approval of the Merger Agreement and the approval of the Transactions, (ii) against any action or agreement (including, without limitation, any amendment of any agreement) that the Shareholder is aware would result in a breach of any representation, warranty, covenant, agreement or other obligation of the Company in the Merger Agreement or any of the Ancillary Agreements, (iii) against any Company

Takeover Proposal and (iv) against any agreement (including, without limitation, any amendment of any agreement), amendment of the Company Charter or other action that is intended or could reasonably be expected to prevent, impede, interfere with, delay, postpone or discourage the consummation of the Merger and/or the other Transactions. Any such vote shall be cast (or consent shall be given) by the Shareholder in accordance with such procedures relating thereto so as to ensure that it is duly counted, including for purposes of determining that a quorum is present and for purposes of recording the results of such vote (or consent). For purposes of this Agreement, “vote” shall include voting in person or by proxy, or otherwise consenting or withholding consent in respect of any action; “voting” shall have a correlative meaning.

(b) Proxy. In furtherance of the Shareholder’s agreement in Section 1(a), but subject to the following sentence, the Shareholder hereby appoints Clifford M.J. Felig, Shaul Grossman, Meir Akunis and Michael Rimon, and each of their designees, and each of them individually, as the Shareholder’s proxy and attorney-in-fact (with full power of substitution), for and in the name, place and stead of the Shareholder, to vote all the Shareholder Shares at any Meeting, or to execute one or more written consents in respect of the Shareholder Shares, (i) in favor of the approval of the Merger Agreement and the Transactions, (ii) against any action or agreement (including, without limitation, any amendment of any agreement) that the Shareholder is aware would result in a breach of any representation, warranty, covenant, agreement or other obligation of the Company in the Merger Agreement or any of the Ancillary Agreements, (iii) against any Company Takeover Proposal and (iv) against any agreement (including, without limitation, any amendment of any agreement), amendment of the Company Charter or other action that is intended or could reasonably be expected to prevent, impede, interfere with, delay, postpone or discourage the consummation of the Merger and/or the Transactions. Such proxy shall (A) be valid and irrevocable until the termination of this Agreement in accordance with Section 3 hereof and (B) automatically terminate upon the termination of this Agreement in accordance with Section 3 hereof. The Shareholder represents that any and all other proxies and voting instructions heretofore given in respect of the Shareholder Shares are revocable, and that such other proxies and voting instructions have been revoked. The Shareholder affirms that the foregoing proxy is: (x) given (I) in connection with the execution of the Merger Agreement and (II) to secure the performance of the Shareholder’s duties under this Agreement, (y) coupled with an interest and may not be revoked except as otherwise provided in this Agreement and (z) intended to be irrevocable prior to termination of this Agreement. All authority herein conferred shall survive the death or incapacity of the Shareholder and shall be binding upon the heirs, estate, administrators, personal representatives, successors and assigns of the Shareholder. To the extent necessary, the Shareholder shall deliver all documents that are reasonably necessary in order to enable the forgoing proxy to be implemented and effected for the purposes set forth therein.

(c) Restriction on Transfer; Proxies; Non-Interference; etc. From the date hereof until any termination of this Agreement in accordance with its terms, the Shareholder shall not directly or indirectly (i) sell, transfer (including by operation of Law), give, pledge, encumber, assign or otherwise dispose of, or enter into any contract, option or other arrangement or understanding with respect to the sale, transfer, gift, pledge, encumbrance, assignment or other disposition of, any Shareholder Shares (or any right, title or interest thereto or therein),

(ii) deposit any Shareholder Shares into a voting trust or grant any proxies or enter into a voting agreement, power of attorney or voting trust with respect to any Shareholder Shares, (iii) take any action that would make any representation or warranty of the Shareholder set forth in this Agreement untrue or incorrect or have the effect of preventing, disabling or delaying the Shareholder from performing any of its obligations under this Agreement or (iv) agree (whether or not in writing) to take any of the actions referred to in the foregoing clauses (i), (ii) or (iii) of this Section 1(c).

(d) No Solicitation. The Shareholder shall not and shall not permit any of his Representatives to, directly or indirectly, take an action that the Company is prohibited from taking by Section 5.02 of the Merger Agreement.

(e) Information for Proxy Statement; Publication. The Shareholder consents to Parent and Merger Sub publishing and disclosing in any filing required under applicable Law the Shareholder’s identity and ownership of Company Ordinary Shares and the nature of the Shareholder’s commitments, arrangements and understandings under this Agreement, as well as attaching a copy of this Agreement as an exhibit to any such filing, if required under applicable Law. The Shareholder represents and warrants to Parent and Merger Sub that none of the information relating to the Shareholder and his, her or its Affiliates provided by or on behalf of the Shareholder or his, her or its Affiliates for inclusion in any such filing will, at the time the such filing is made or distributed, contain any untrue statement of a material fact or omit to state any material fact required to be stated therein or necessary in order to make the statements therein, in light of the circumstances under which they were made, not misleading. The Shareholder shall not issue any press release or make any other public statement or other disclosure with respect to this Agreement, the Merger Agreement or the Transactions without the prior written consent of Parent, except as may be required by applicable Law and in case any such requirement under applicable Law arises, after giving Parent reasonable opportunity to comment on any such press release or statement and including all reasonably requested comments of Parent.

(f) Rights Attached to Shares. Without derogating from any provisions to the contrary in this Agreement or the Merger Agreement, to the extent permitted under applicable Law, the provisions of this Section 1 and the obligations hereunder shall attach to the Shareholder Shares and shall be binding upon any person to which legal or beneficial ownership of the Shareholder Shares shall pass, whether by operation of Law or otherwise, including, without limitation, the Shareholder’s administrators or successors. Without derogating from Section 1(c), notwithstanding any transfer of the Shareholder Shares, the transferor shall remain liable for the performance of all obligations of the Shareholder hereunder.

(g) Acknowledgment. The Shareholder understands and acknowledges that Parent and Merger Sub are entering into the Merger Agreement in reliance upon the Shareholder’s execution, delivery and performance of this Agreement.

(h) Amendments to the Merger Agreement. If, at any time, the Merger Agreement is amended, without the prior written consent of the Shareholder, (i) to reduce the Merger Consideration in any respect, or (ii) in a manner that is materially adverse to the Company or its shareholders, then the obligations of the Shareholder under Section 1(a) and 1(b) shall be null and void.

2. Representations and Warranties of the Shareholder. The Shareholder hereby represents and warrants to Parent as follows:

(a) Authority. The Shareholder has all necessary power and authority to execute and deliver this Agreement and to perform his obligations under this Agreement. This Agreement has been duly executed and delivered by the Shareholder and, constitutes a valid and binding obligation of the Shareholder, enforceable against the Shareholder in accordance with its terms.

(b) Consents and Approvals; No Violations. Other than filings under the Exchange Act and other than such as, if not made, obtained or given, would not reasonably be expected to prevent or delay the performance by the Shareholder of any of his obligations under this Agreement or the consummation of the Transactions, no notices, reports or other filings are required to be made by the Shareholder with, nor are any consents, registrations, approvals, permits or authorizations required to be obtained by such the Shareholder from, any Governmental Entity or any other Person, in connection with the execution and delivery of this Agreement by the Shareholder and the performance by the Shareholder of his obligations hereunder. The execution and delivery by the Shareholder of this Agreement do not, and the consummation of the Merger and the other Transactions and compliance by the Shareholder with the terms hereof and thereof will not (i) contravene, conflict with, or result in any violation of or default (with or without notice or lapse of time, or both) under, (ii) give rise to a right of termination, cancelation or acceleration of any obligation or to a right to challenge the Transactions under, or (iii) result in the creation of any Lien upon any of the properties or assets of the Shareholder under (A) any Contract to which the Shareholder is a party or by which the Shareholder is bound, or (B) any Law or Judgment applicable to the Shareholder, except for such contraventions, conflicts, violations, defaults, terminations, cancellations, modifications, accelerations or Liens that would not reasonably be expected to prevent or delay the performance by the Shareholder of any of his obligations under this Agreement or the consummation of the Transactions.

(c) Ownership of Shares. Shareholder owns, beneficially and (except for Shareholder Shares held of record by Rad Data Ltd., Lomsha Ltd. and Michael and Klil Holdings (93) Ltd.) of record, all of the Shareholder Shares free and clear of any proxy, voting restriction, adverse claim or other Lien (other than proxies and restrictions in favor of Parent pursuant to this Agreement). Without limiting the foregoing, except for proxies and restrictions in favor of Parent pursuant to this Agreement, the Shareholder has sole voting power and sole power of disposition with respect to all Shareholder Shares, with no restrictions on the Shareholder’s rights of voting or disposition pertaining thereto and no Person other than the Shareholder has any right to direct or approve the voting or disposition of any Shareholder Shares. As of the date hereof, the Shareholder does not own, beneficially or of record, nor has the power to vote or control the voting of, any securities of the Company other than the Company Ordinary Shares which constitute Shareholder Shares and the Shareholder Options.

(d) Brokers. No broker, investment banker, financial advisor or other Person is entitled to any broker’s finders, financial advisor’s or other similar fee or commission in connection with the Merger and the other Transactions based upon arrangements made by or on behalf of the Shareholder.

3. Termination. This Agreement shall terminate on the first to occur of (a) the termination of the Merger Agreement in accordance with its terms and (b) the Effective Time. Notwithstanding the foregoing, (i) nothing herein shall relieve any party from liability for any breach of this Agreement and (ii) the provisions of Section 2, this Section 3 and Section 4 of this Agreement shall survive any termination of this Agreement.

4. Miscellaneous.

(a) Expenses. Except as otherwise expressly provided in this Agreement, all costs and expenses incurred in connection with the transactions contemplated by this Agreement shall be paid by the party incurring such costs and expenses.

(b) Additional Shares. Until any termination of this Agreement in accordance with its terms, the Shareholder shall promptly notify Parent of the number of Company Ordinary Shares, if any, as to which the Shareholder acquires record or beneficial ownership after the date hereof. Without limiting the foregoing, in the event of any share split, share dividend, reclassification, recapitalization or other change in the capital structure of the Company affecting the Company Ordinary Shares, the number of Company Ordinary Shares constituting Shareholder Shares shall be adjusted appropriately and this Agreement and the obligations hereunder shall attach to any additional Company Ordinary Shares or other voting securities of the Company issued to or exchanged with the Shareholder in connection therewith.

(c) Definition of “Beneficial Ownership”. For purposes of this Agreement, “beneficial ownership” with respect to (or to “own beneficially”) any securities shall mean having “beneficial ownership” of such securities (as determined pursuant to Rule 13d-3 under the Exchange Act), including pursuant to any agreement, arrangement or understanding, whether or not in writing.

(d) Further Assurances. From time to time, at the request of Parent and without further consideration, the Shareholder shall execute and deliver such additional documents and take all such further action as may be reasonably required to give effect to the obligations of the Shareholder hereunder and to confirm the rights of Parent hereunder, in the most expeditious manner practicable.

(e) Entire Agreement; No Third Party Beneficiaries. This Agreement constitutes the entire agreement, and supersedes all prior agreements and understandings, both written and oral, among the parties with respect to the subject matter hereof. This Agreement is not intended to confer upon any Person other than the parties any rights or remedies.

(f) Assignment; Binding Effect. Neither this Agreement nor any of the rights, interests or obligations under this Agreement shall be assigned, in whole or in part, by

operation of law or otherwise by any of the parties without the prior written consent of the other parties. Any purported assignment without such consent shall be void. Subject to the preceding sentences, this Agreement will be binding upon, inure to the benefit of, and be enforceable by, the parties and their respective successors and assigns.

(g) Amendments; Waiver. This Agreement may not be amended or supplemented, except by a written agreement executed by the parties hereto. Any party to this Agreement may (A) waive any inaccuracies in the representations and warranties of any other party hereto or extend the time for the performance of any of the obligations or acts of any other party hereto or (B) waive compliance by the other party with any of the agreements contained herein. Notwithstanding the foregoing, no failure or delay by Parent in exercising any right hereunder shall operate as a waiver thereof nor shall any single or partial exercise thereof preclude any other or further exercise thereof or the exercise of any other right hereunder. Any agreement on the part of a party hereto to any such extension or waiver shall be valid only if set forth in an instrument in writing signed on behalf of such party.

(h) Severability. If any term or other provision of this Agreement is determined by a court of competent jurisdiction to be invalid, illegal or incapable of being enforced by any rule of Law or public policy, all other terms, provisions and conditions of this Agreement shall nevertheless remain in full force and effect. Upon such determination that any term or other provision is invalid, illegal or incapable of being enforced, the parties hereto shall negotiate in good faith to modify this Agreement so as to effect the original intent of the parties as closely as possible to the fullest extent permitted by applicable Law in an acceptable manner to the end that the transactions contemplated hereby are fulfilled to the extent possible.

(i) Counterparts. This Agreement may be executed in one or more counterparts, all of which shall be considered one and the same agreement and shall become effective when one or more counterparts have been signed by each of the parties and delivered to the other parties.

(j) Descriptive Headings. The headings contained in this Agreement are for reference purposes only and shall not affect in any way the meaning or interpretation of this Agreement.

(k) Notices. All notices, requests and other communications to any party hereunder shall be in writing (including facsimile transmission) and shall be given,

or such other address or facsimile number as such party may hereafter specify for the purpose by notice to the other parties hereto. All such notices, requests and other communications shall be deemed received on the date of receipt by the recipient thereof if received prior to 5 P.M. in the place of receipt and such day is a business day in the place of receipt. Otherwise, any such notice, request or communication shall be deemed not to have been received until the next succeeding business day in the place of receipt.

(l) Drafting. The parties have participated jointly in negotiating and drafting this Agreement. In the event that an ambiguity or a question of intent or interpretation arises, this Agreement shall be construed as if drafted jointly by the parties, and no presumption or burden of proof shall arise favoring or disfavoring any party by virtue of the authorship of any provision of this Agreement.

(m) Governing Law. This Agreement, and all claims or causes of action (whether in contract or tort) that may be based upon, arise out of or relate to this Agreement, or the negotiation, execution or performance of this Agreement (including any claim or cause of action based upon, arising out of or related to any representation or warranty made in or in connection with this Agreement or as an inducement to enter into this Agreement), shall be governed by the internal laws of the State of Israel applicable to agreements made and to be performed entirely within such state, without regard to any conflicts of law principles of such state that would cause the laws of another jurisdiction to be applicable.

(n) Enforcement. The parties agree that irreparable damage would occur in the event that any of the provisions of this Agreement were not performed in accordance with their specific terms or were otherwise breached. It is accordingly agreed that, the parties shall be entitled to an injunction or injunctions to prevent breaches of this Agreement and to enforce specifically the terms and provisions of this Agreement in any court in the State of Israel, this being in addition to any other remedy to which they are entitled at law or in equity. In addition, each of the parties hereto (a) consents to submit itself to the exclusive personal jurisdiction of any competent court in Tel-Aviv-Jaffa, Israel in the event any dispute arises out of this Agreement or any Transaction, (b) agrees that it will not attempt to deny or defeat such personal jurisdiction by motion or other request for leave from any such court, (c) agrees that it will not bring any action relating to this Agreement or any Transaction in any court other than in the State of Israel and (d) waives any right to trial by jury with respect to any action related to or arising out of this Agreement or any Transaction, to the extent applicable.

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IN WITNESS WHEREOF, the parties have caused this Agreement to be duly executed as of the date first above written.

[Signature Page To Voting And Support Agreement – Zohar Zisapel]

[Signature Page To Voting And Support Agreement – Zohar Zisapel]

Exhibit 99.3

VOTING AND SUPPORT AGREEMENT

VOTING AND SUPPORT AGREEMENT (this “Agreement”), dated as of March 14, 2012, by and between Avaya Inc., a Delaware corporation (“Parent”), and the undersigned Shareholder (the “Shareholder”) of Radvision Ltd., a corporation incorporated under the laws of the State of Israel (the “Company”).

WHEREAS, concurrently with the execution of this Agreement, the Company, Parent and Sonic Acquisition Ltd. (“Merger Sub”) are entering into a Merger Agreement as of the date hereof (such Merger Agreement, as it may be amended from time to time, the “Merger Agreement”);

WHEREAS, capitalized terms used but not defined in this Agreement have the meanings ascribed to them in the Merger Agreement;

WHEREAS, as of the date hereof, the Shareholder is the beneficial owner of 1,154,737 Company Ordinary Shares (such Company Ordinary Shares, together with any other Company Ordinary Shares acquired by the Shareholder after the date hereof or as to which the Shareholder is or becomes the beneficial owner or is otherwise able to direct the voting thereof, being collectively referred to herein as the “Shareholder Shares”);

WHEREAS, as a condition to their willingness to enter into the Merger Agreement, Parent and Merger Sub have required that the Shareholder enter into this Agreement; and

WHEREAS, in order to induce Parent and Merger Sub to enter into the Merger Agreement, the Company asked the Shareholder to enter into this Agreement with Parent and Merger Sub, and the Shareholder has agreed and is willing to enter into this Agreement.

NOW, THEREFORE, in consideration of the foregoing and the mutual covenants and agreements contained herein, the parties hereto, intending to be legally bound hereby, agree as follows:

1. Agreements of the Shareholder.

(a) Voting. From the date hereof until any termination of this Agreement in accordance with its terms, at any meeting of the shareholders of the Company however called (or any action by written consent in lieu of a meeting) or any adjournment thereof (a “Meeting”), the Shareholder shall vote all the Shareholder Shares (or cause them to be voted) or (as appropriate) execute written consents in respect thereof, (i) in favor of the approval of the Merger Agreement and the approval of the Transactions, (ii) against any action or agreement (including, without limitation, any amendment of any agreement) that the Shareholder is aware would result in a breach of any representation, warranty, covenant, agreement or other obligation of the Company in the Merger Agreement or any of the Ancillary Agreements, (iii) against any Company Takeover Proposal and (iv) against any agreement (including, without limitation, any amendment of any agreement), amendment of the Company Charter or other action that is intended or could reasonably be expected to prevent, impede, interfere with, delay, postpone or

discourage the consummation of the Merger and/or the other Transactions. Any such vote shall be cast (or consent shall be given) by the Shareholder in accordance with such procedures relating thereto so as to ensure that it is duly counted, including for purposes of determining that a quorum is present and for purposes of recording the results of such vote (or consent). For purposes of this Agreement, “vote” shall include voting in person or by proxy, or otherwise consenting or withholding consent in respect of any action; “voting” shall have a correlative meaning.

(b) Proxy. In furtherance of the Shareholder’s agreement in Section 1(a), but subject to the following sentence, the Shareholder hereby appoints Clifford M.J. Felig, Shaul Grossman, Meir Akunis and Michael Rimon, and each of their designees, and each of them individually, as the Shareholder’s proxy and attorney-in-fact (with full power of substitution), for and in the name, place and stead of the Shareholder, to vote all the Shareholder Shares at any Meeting, or to execute one or more written consents in respect of the Shareholder Shares, (i) in favor of the approval of the Merger Agreement and the Transactions, (ii) against any action or agreement (including, without limitation, any amendment of any agreement) that the Shareholder is aware would result in a breach of any representation, warranty, covenant, agreement or other obligation of the Company in the Merger Agreement or any of the Ancillary Agreements, (iii) against any Company Takeover Proposal and (iv) against any agreement (including, without limitation, any amendment of any agreement), amendment of the Company Charter or other action that is intended or could reasonably be expected to prevent, impede, interfere with, delay, postpone or discourage the consummation of the Merger and/or the Transactions. Such proxy shall (A) be valid and irrevocable until the termination of this Agreement in accordance with Section 3 hereof and (B) automatically terminate upon the termination of this Agreement in accordance with Section 3 hereof. The Shareholder represents that any and all other proxies and voting instructions heretofore given in respect of the Shareholder Shares are revocable, and that such other proxies and voting instructions have been revoked. The Shareholder affirms that the foregoing proxy is: (x) given (I) in connection with the execution of the Merger Agreement and (II) to secure the performance of the Shareholder’s duties under this Agreement, (y) coupled with an interest and may not be revoked except as otherwise provided in this Agreement and (z) intended to be irrevocable prior to termination of this Agreement. All authority herein conferred shall survive the death or incapacity of the Shareholder and shall be binding upon the heirs, estate, administrators, personal representatives, successors and assigns of the Shareholder. To the extent necessary, the Shareholder shall deliver all documents that are reasonably necessary in order to enable the forgoing proxy to be implemented and effected for the purposes set forth therein.

(c) Restriction on Transfer; Proxies; Non-Interference; etc. From the date hereof until any termination of this Agreement in accordance with its terms, the Shareholder shall not directly or indirectly (i) sell, transfer (including by operation of Law), give, pledge, encumber, assign or otherwise dispose of, or enter into any contract, option or other arrangement or understanding with respect to the sale, transfer, gift, pledge, encumbrance, assignment or other disposition of, any Shareholder Shares (or any right, title or interest thereto or therein), (ii) deposit any Shareholder Shares into a voting trust or grant any proxies or enter into a voting agreement, power of attorney or voting trust with respect to any Shareholder Shares, (iii) take any action that would make any representation or warranty of the Shareholder set forth in this

Agreement untrue or incorrect or have the effect of preventing, disabling or delaying the Shareholder from performing any of its obligations under this Agreement or (iv) agree (whether or not in writing) to take any of the actions referred to in the foregoing clauses (i), (ii) or (iii) of this Section 1(c).

(d) No Solicitation. The Shareholder shall not and shall not permit any of his Representatives to, directly or indirectly, take an action that the Company is prohibited from taking by Section 5.02 of the Merger Agreement.

(e) Information for Proxy Statement; Publication. The Shareholder consents to Parent and Merger Sub publishing and disclosing in any filing required under applicable Law the Shareholder’s identity and ownership of Company Ordinary Shares and the nature of the Shareholder’s commitments, arrangements and understandings under this Agreement, as well as attaching a copy of this Agreement as an exhibit to any such filing, if required under applicable Law. The Shareholder represents and warrants to Parent and Merger Sub that none of the information relating to the Shareholder and his, her or its Affiliates provided by or on behalf of the Shareholder or his, her or its Affiliates for inclusion in any such filing will, at the time the such filing is made or distributed, contain any untrue statement of a material fact or omit to state any material fact required to be stated therein or necessary in order to make the statements therein, in light of the circumstances under which they were made, not misleading. The Shareholder shall not issue any press release or make any other public statement or other disclosure with respect to this Agreement, the Merger Agreement or the Transactions without the prior written consent of Parent, except as may be required by applicable Law and in case any such requirement under applicable Law arises, after giving Parent reasonable opportunity to comment on any such press release or statement and including all reasonably requested comments of Parent.

(f) Rights Attached to Shares. Without derogating from any provisions to the contrary in this Agreement or the Merger Agreement, to the extent permitted under applicable Law, the provisions of this Section 1 and the obligations hereunder shall attach to the Shareholder Shares and shall be binding upon any person to which legal or beneficial ownership of the Shareholder Shares shall pass, whether by operation of Law or otherwise, including, without limitation, the Shareholder’s administrators or successors. Without derogating from Section 1(c), notwithstanding any transfer of the Shareholder Shares, the transferor shall remain liable for the performance of all obligations of the Shareholder hereunder.

(g) Acknowledgment. The Shareholder understands and acknowledges that Parent and Merger Sub are entering into the Merger Agreement in reliance upon the Shareholder’s execution, delivery and performance of this Agreement.

(h) Amendments to the Merger Agreement. If, at any time, the Merger Agreement is amended, without the prior written consent of the Shareholder, (i) to reduce the Merger Consideration in any respect, or (ii) in a manner that is materially adverse to the Company or its shareholders, then the obligations of the Shareholder under Section 1(a) and 1(b) shall be null and void.

2. Representations and Warranties of the Shareholder. The Shareholder hereby represents and warrants to Parent as follows:

(a) Authority. The Shareholder has all necessary power and authority to execute and deliver this Agreement and to perform his obligations under this Agreement. This Agreement has been duly executed and delivered by the Shareholder and, constitutes a valid and binding obligation of the Shareholder, enforceable against the Shareholder in accordance with its terms.

(b) Consents and Approvals; No Violations. Other than filings under the Exchange Act and other than such as, if not made, obtained or given, would not reasonably be expected to prevent or delay the performance by the Shareholder of any of his obligations under this Agreement or the consummation of the Transactions, no notices, reports or other filings are required to be made by the Shareholder with, nor are any consents, registrations, approvals, permits or authorizations required to be obtained by such the Shareholder from, any Governmental Entity or any other Person, in connection with the execution and delivery of this Agreement by the Shareholder and the performance by the Shareholder of his obligations hereunder. The execution and delivery by the Shareholder of this Agreement do not, and the consummation of the Merger and the other Transactions and compliance by the Shareholder with the terms hereof and thereof will not (i) contravene, conflict with, or result in any violation of or default (with or without notice or lapse of time, or both) under, (ii) give rise to a right of termination, cancelation or acceleration of any obligation or to a right to challenge the Transactions under, or (iii) result in the creation of any Lien upon any of the properties or assets of the Shareholder under (A) any Contract to which the Shareholder is a party or by which the Shareholder is bound, or (B) any Law or Judgment applicable to the Shareholder, except for such contraventions, conflicts, violations, defaults, terminations, cancellations, modifications, accelerations or Liens that would not reasonably be expected to prevent or delay the performance by the Shareholder of any of his obligations under this Agreement or the consummation of the Transactions.

(c) Ownership of Shares. Shareholder owns, beneficially and (except for 402,836 Shareholder Shares which are held of record by RADbit Inc.) of record, all of the Shareholder Shares free and clear of any proxy, voting restriction, adverse claim or other Lien (other than proxies and restrictions in favor of Parent pursuant to this Agreement). Without limiting the foregoing, except for proxies and restrictions in favor of Parent pursuant to this Agreement, the Shareholder has sole voting power and sole power of disposition with respect to all Shareholder Shares, with no restrictions on the Shareholder’s rights of voting or disposition pertaining thereto and no Person other than the Shareholder has any right to direct or approve the voting or disposition of any Shareholder Shares. As of the date hereof, the Shareholder does not own, beneficially or of record, nor has the power to vote or control the voting of, any securities of the Company other than the Company Ordinary Shares which constitute Shareholder Shares.

(d) Brokers. No broker, investment banker, financial advisor or other Person is entitled to any broker’s finders, financial advisor’s or other similar fee or commission in connection with the Merger and the other Transactions based upon arrangements made by or on behalf of the Shareholder.

3. Termination. This Agreement shall terminate on the first to occur of (a) the termination of the Merger Agreement in accordance with its terms and (b) the Effective Time. Notwithstanding the foregoing, (i) nothing herein shall relieve any party from liability for any breach of this Agreement and (ii) the provisions of Section 2, this Section 3 and Section 4 of this Agreement shall survive any termination of this Agreement.

4. Miscellaneous.

(a) Expenses. Except as otherwise expressly provided in this Agreement, all costs and expenses incurred in connection with the transactions contemplated by this Agreement shall be paid by the party incurring such costs and expenses.

(b) Additional Shares. Until any termination of this Agreement in accordance with its terms, the Shareholder shall promptly notify Parent of the number of Company Ordinary Shares, if any, as to which the Shareholder acquires record or beneficial ownership after the date hereof. Without limiting the foregoing, in the event of any share split, share dividend, reclassification, recapitalization or other change in the capital structure of the Company affecting the Company Ordinary Shares, the number of Company Ordinary Shares constituting Shareholder Shares shall be adjusted appropriately and this Agreement and the obligations hereunder shall attach to any additional Company Ordinary Shares or other voting securities of the Company issued to or exchanged with the Shareholder in connection therewith.

(c) Definition of “Beneficial Ownership”. For purposes of this Agreement, “beneficial ownership” with respect to (or to “own beneficially”) any securities shall mean having “beneficial ownership” of such securities (as determined pursuant to Rule 13d-3 under the Exchange Act), including pursuant to any agreement, arrangement or understanding, whether or not in writing.

(d) Further Assurances. From time to time, at the request of Parent and without further consideration, the Shareholder shall execute and deliver such additional documents and take all such further action as may be reasonably required to give effect to the obligations of the Shareholder hereunder and to confirm the rights of Parent hereunder, in the most expeditious manner practicable.

(e) Entire Agreement; No Third Party Beneficiaries. This Agreement constitutes the entire agreement, and supersedes all prior agreements and understandings, both written and oral, among the parties with respect to the subject matter hereof. This Agreement is not intended to confer upon any Person other than the parties any rights or remedies.

(f) Assignment; Binding Effect. Neither this Agreement nor any of the rights, interests or obligations under this Agreement shall be assigned, in whole or in part, by operation of law or otherwise by any of the parties without the prior written consent of the other parties. Any purported assignment without such consent shall be void. Subject to the preceding sentences, this Agreement will be binding upon, inure to the benefit of, and be enforceable by, the parties and their respective successors and assigns.

(g) Amendments; Waiver. This Agreement may not be amended or supplemented, except by a written agreement executed by the parties hereto. Any party to this Agreement may (A) waive any inaccuracies in the representations and warranties of any other party hereto or extend the time for the performance of any of the obligations or acts of any other party hereto or (B) waive compliance by the other party with any of the agreements contained herein. Notwithstanding the foregoing, no failure or delay by Parent in exercising any right hereunder shall operate as a waiver thereof nor shall any single or partial exercise thereof preclude any other or further exercise thereof or the exercise of any other right hereunder. Any agreement on the part of a party hereto to any such extension or waiver shall be valid only if set forth in an instrument in writing signed on behalf of such party.

(h) Severability. If any term or other provision of this Agreement is determined by a court of competent jurisdiction to be invalid, illegal or incapable of being enforced by any rule of Law or public policy, all other terms, provisions and conditions of this Agreement shall nevertheless remain in full force and effect. Upon such determination that any term or other provision is invalid, illegal or incapable of being enforced, the parties hereto shall negotiate in good faith to modify this Agreement so as to effect the original intent of the parties as closely as possible to the fullest extent permitted by applicable Law in an acceptable manner to the end that the transactions contemplated hereby are fulfilled to the extent possible.

(i) Counterparts. This Agreement may be executed in one or more counterparts, all of which shall be considered one and the same agreement and shall become effective when one or more counterparts have been signed by each of the parties and delivered to the other parties.

(j) Descriptive Headings. The headings contained in this Agreement are for reference purposes only and shall not affect in any way the meaning or interpretation of this Agreement.

(k) Notices. All notices, requests and other communications to any party hereunder shall be in writing (including facsimile transmission) and shall be given,