INTELLECTUAL PROPERTY SECURITY AGREEMENT

Exhibit 10.30

INTELLECTUAL PROPERTY SECURITY AGREEMENT

This Intellectual Property Security Agreement (this “IP Agreement”) is made as of the 28th day of September, 2005, by and between ARTISOFT, INC., a Delaware corporation with its principal place of business at 5 Cambridge Center, Cambridge, Massachusetts (“Grantor”), and SILICON VALLEY BANK, a California-chartered bank, with its principal place of business at 3003 Tasman Drive, Santa Clara, California 95054 and with a loan production office located at One Newton Executive Park, Suite 200, 2221 Washington Street, Newton, Massachusetts 02462, doing business under the name “Silicon Valley East” (“Lender”).

RECITALS

A. Lender has agreed to make advances of money and to extend certain financial accommodations to Grantor and VERTICAL COMMUNICATIONS ACQUISITION CORP., a Delaware corporation (the “Loan”), pursuant to a certain Loan and Security Agreement of even date herewith (as may be amended, the “Loan Agreement”). The Loan is secured pursuant to the terms of the Loan Agreement. Lender is willing to enter into certain financial accommodations with Grantor, but only upon the condition, among others, that Grantor shall grant to Lender a security interest in certain Copyrights, Trademarks, Patents, and Mask Works, and other assets, to secure the obligations of Grantor under the Loan Agreement. Defined terms used but not defined herein shall have the same meanings as in the Loan Agreement.

B. Pursuant to the terms of the Loan Agreement, Grantor has granted to Lender a security interest in all of Grantor’s right title and interest, whether presently existing or hereafter acquired in, to and under all of the Collateral (as defined therein).

NOW, THEREFORE, for good and valuable consideration, receipt of which is hereby acknowledged and intending to be legally bound, as collateral security for the prompt and complete payment when due of Grantor’s Indebtedness (as defined below), Grantor hereby represents, warrants, covenants and agrees as follows:

1. Grant of Security Interest. As collateral security for the prompt and complete payment and performance of all of Grantor’s present or future indebtedness, obligations and liabilities to Lender (hereinafter, the “Indebtedness”), including, without limitation, under the Loan Agreement, Grantor hereby grants a security interest in all of Grantor’s right, title and interest in, to and under its registered and unregistered intellectual property collateral (all of which shall collectively be called the “Intellectual Property Collateral”), including, without limitation, the following:

(a) Any and all copyright rights, copyright applications, copyright registrations and like protections in each work or authorship and derivative work thereof, whether published or unpublished, registered or unregistered, and whether or not the same also constitutes a trade secret, now or hereafter existing, created, acquired or held, including without limitation those set forth on EXHIBIT A attached hereto (collectively, the “Copyrights”);

(b) Any and all trade secret rights, including any rights to unpatented inventions, know-how, operating manuals, license rights and agreements, and confidential information, and any and all intellectual property rights in computer software and computer software products now or hereafter existing, created, acquired or held;

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(c) Any and all design rights which may be available to Grantor now or hereafter existing, created, acquired or held;

(d) All patents, patent applications and like protections including, without limitation, improvements, divisions, continuations, renewals, reissues, extensions and continuations-in-part of the same, including, without limitation, the patents and patent applications set forth on EXHIBIT B attached hereto (collectively, the “Patents”);

(e) Any trademark and service mark rights, slogans, trade dress, and tradenames, trade styles, whether registered or not, applications to register and registrations of the same and like protections, and the entire goodwill of the business of Grantor connected with and symbolized by such trademarks, including, without limitation, those set forth on EXHIBIT C attached hereto (collectively, the “Trademarks”);

(f) All mask works or similar rights available for the protection of semiconductor chips, now owned or hereafter acquired, including, without limitation, those set forth on EXHIBIT D attached hereto (collectively, the “Mask Works”);

(g) Any and all claims for damages by way of past, present and future infringements of any of the rights included above, with the right, but not the obligation, to sue for and collect such damages for said use or infringement of the intellectual property rights identified above;

(h) All licenses or other rights to use any of the Copyrights, Patents, Trademarks, or Mask Works and all license fees and royalties arising from such use to the extent permitted by such license or rights, including, without limitation, those set forth on EXHIBIT E attached hereto;

(i) All amendments, extensions, renewals and extensions of any of the Copyrights, Trademarks, Patents, or Mask Works; and

(j) All proceeds and products of the foregoing, including, without limitation, all payments under insurance or any indemnity or warranty payable in respect of any of the foregoing.

2. Authorization and Request. Grantor authorizes and requests that the Register of Copyrights and the Commissioner of Patents and Trademarks record this IP Agreement, or a copy thereof.

3. Covenants and Warranties. Grantor represents, warrants, covenants and agrees as follows:

(a) Grantor is now the sole owner of the Intellectual Property Collateral, except for non-exclusive licenses granted by Grantor to its customers in the ordinary course of business. Lender recognizes that some of the Intellectual Property Collateral is being acquired by Grantor pursuant to provisions of the Asset Purchase Agreement dated as of September 1, 2005 between Comdial Corporation and Vertical Communications Acquisition Corp. and that as of the date of this IP Agreement, record ownership for such acquired Intellectual Property Collateral has not been transferred to Grantor.

(b) Performance of this IP Agreement does not conflict with or result in a breach of any material agreement to which Grantor is bound.

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(c) During the term of this IP Agreement, Grantor will not transfer or otherwise encumber any interest in any Intellectual Property Collateral, except for non-exclusive licenses granted by Grantor in the ordinary course of business or as set forth in this IP Agreement;

(d) To its knowledge, each of the Patents is valid and enforceable, and no part of the Intellectual Property Collateral has been judged invalid or unenforceable, in whole or in part, and, except for disputes in the ordinary course of business where an adverse ruling would not have a material adverse effect to Grantor, no claim has been made that any part of the Intellectual Property Collateral violates the rights of any third party;

(e) Grantor shall promptly advise Lender of any material adverse change in the composition of the Collateral, including but not limited to, any subsequent ownership right of the Grantor in or to any Trademark, Patent, Copyright, or Mask Work specified in this IP Agreement;

(f) Grantor shall (i) protect, defend and maintain the validity and enforceability of the Trademarks, Patents, Copyrights, and Mask Works, (ii) use its best efforts to detect infringements of the Trademarks, Patents, Copyrights, and Mask Works and promptly advise Lender in writing