**EXHIBIT10.18**

**FORM OFNOTE SALE AGREEMENT**

NoteSale Agreement dated as __________ ___, _____ (this “**Agreement**”)by and between JPMorgan Chase Bank, N.A. (the “**Seller**”)and [Gerald J. Burnett] [and]  [Gerald J.Burnett and Marjorie J. Burnett as trustees of The Gerald J. Burnett andMarjorie J. Burnett Revocable Trust] (individually, or if more than one,collectively, the “Buyer”).

TheSeller is the holder of the Revolving Credit Promissory Note (Libor/Prime)dated as of December 23, 2006 executed and delivered by AvistarCommunications Corporation, a Delaware corporation (the “**Borrower**”),to the Seller (as from time to time may be amended, modified or replaced, the “**Note**”).

TheSeller and the Borrower are parties to a Security Agreement dated as ofDecember 23, 2006 by which the Borrower, among other things, granted theSeller security interests in the “Collateral” (as defined therein) to securethe Borrower’s obligations under the Note (as from time to time may be amended,modified or replaced, the “**Security Agreement**”).

Toinduce the Seller to accept the Note, the Buyer [and [Gerald J. Burnett][Gerald J. Burnett and Marjorie J. Burnett as trustees of The Gerald J. Burnettand Marjorie J. Burnett Revocable Trust] (the together with the Buyer the “**Guarantors**”)]****delivered tothe Seller its Guaranty dated as of December 23, 2006,  (the “**Guaranty**”) inwhich the [Buyer] [Guarantors] guaranteed payment and performance of the Note(reference is made to the Guaranty for a complete statement of its terms andconditions).

TheSeller has made a demand for payment under the Guaranty, and the Buyer haselected to purchase the Loan by executing and delivering to the Seller thisAgreement on or before the Due Date (the “**Offer**”).

NOWTHEREFORE, the Buyer (and if more than one, jointly and severally) and theSeller agree as follows:

1.                                       **Definitions: **The following terms shall be defined asfollows:

1.1**                                 “BankingDay”**means any****day on whichcommercial banks are not authorized or required to close in New York City.

1.2                                 **“Closing”**means the simultaneous delivery by the Seller andthe Buyer of documents and funds, and the performance of the acts hereinprovided to be performed at the Closing.

1.3                                 **“Closing Date”**means the first (1st) Banking Day after the Seller’s receiptof the Offer, unless the Seller, in its discretion, deems it necessary toextend such time.

1.4                                 “**Due Date**” has the meaning given such term in the Guaranty.

1.5                                 **“Facility Documents”** has the meaning given such term in theNote.

1.6                                 **“Loan”** means the Note and the Security Agreement and theSeller’s rights thereunder.

1.7                                 **“Note Purchase Price”** means the principal amount outstandingunder the Note as of the Closing Date, together with any interest thereon, andany costs and expenses under any Facility Document, all as calculated by theSeller.

2.                                       **Terms and Conditions of Sale:**  The Seller agrees to sell, assign, transfer,and convey to the Buyer, on the terms and conditions set forth in thisAgreement, all the right, title, and interest of the Seller, as of the ClosingDate, in and to the Loan.  The Buyeracknowledges and agrees (a) that the Seller’s sale of the Loan to the Buyer isirrevocable and (b) that the Buyer shall have no recourse to the Seller.

----

3.                                       **Note Purchase Price: **The****Buyer shallpay to the Seller, by 2:00 p.m. (New York City time), by cashier’s check orwire transfer, the amount of the Note Purchase Price.  All payments of the Note received by theSeller before the Closing Date shall belong to the Seller.  All payments of the Note received by theSeller on or after the Closing Date shall belong to the Buyer.  In the event that a draft the Seller hasreceived in payment of the Note is dishonored after the Closing Date, anadjustment to the Note Purchase Price in the Seller’s favor shall be made uponnotification by the Seller to the Buyer that the check has been dishonored, andthe Buyer shall promptly forward that amount to the Seller.

4.                                       **Place of Closing: **The Closing shall be held at the Seller’soffices located at 270 Park Avenue, New York, New York, or such other place as may be practicable.  The Closing shall, at the Seller’s option, beeither by telephone, confirmed by letter or wire, or conducted in person at theplace designated by the Seller.

5.                                       **Endorsement and Delivery:**  The Seller agrees to endorse the Note, anddeliver the endorsed Note to the Buyer, as soon as practicable after theClosing Date.  The endorsement will be inthe following form:

For value received, payto the order of **[Gerald J. Burnett] [and]  [Gerald J. Burnett and Marjorie J. Burnett astrustees of The Gerald J. Burnett and Marjorie J. Burnett Revocable Trust]**withoutrecourse and without any representation or warranty either express or impliedin fact or by law.
|            | ** ** | **JPMORGAN  CHASE BANK, N.A.** |
|------------|------------|--------------------------------|
| ** ** | ** ** | ** **                     | ** ** |
| ** ** | ** ** | By:                            | ** ** |
| ** ** | ** ** | ** **                     | Name: |
| ** ** | ** ** | ** **                     | Title: |

 

After the Closing, the Seller agrees to execute and****deliver to the Buyer any such documents or instrumentsreasonably requested by Buyer to transfer to Buyer****allright, title and interest of Seller in and to the Loan, provided that (i) theBuyer prepares such documents or instruments at its expense and (ii) the Buyerprovides such documents or instruments to the Seller within thirty (30) daysafter the Closing

6.                                       **Representations, Warranties and Agreements of theBuyer:**  The Buyerrepresents, warrants and agrees as follows:

6.1                                 TheBuyer will not violate any laws relating to unfair credit collection practicesin connection with the Loan.  The Buyerwill indemnify the Seller and hold the Seller harmless from and against any andall claims, demands, losses, damages, penalties, fines, forfeitures, judgments,legal fees and any other costs, fees, and expenses heretofore or hereafterincurred by the Seller as a result of (i) a breach by the Buyer of theaforesaid agreement or (ii) any claim, demand or assertion that the Buyer orthe Seller was in any way involved in or had in any way authorized any unlawfulcollection practices in connection with the Loan or (iii) any claim, demand orassertion by the Borrower in connection with the Loan.  The Buyer agrees to notify the Seller withinthree (3) Banking Days of notice or knowledge of any such claim or demand.

6.2                                 TheBuyer will not institute any legal action in the name of the Seller or continueto prosecute in the name of the Seller any pending legal action nor shall theBuyer intentionally or unintentionally, through misrepresentation ornondisclosure, mislead or conceal that the Buyer’s ownership of the Loanfollowing the Closing.  The Buyeracknowledges that there is no adequate remedy at law for violation of thissubparagraph

2

----

and consents to the entryof an order by a court of competent jurisdiction enjoining any violation orthreatened violation of the provisions of this subparagraph.  The Buyer will indemnify the Seller and holdthe Seller harmless from and against any and all claims, demands, losses,damages, judgments, legal fees and any other costs, fees and expensesheretofore or hereafter incurred by the Seller as a result of a breach by theBuyer of the aforesaid agreement.

6.3                                 TheBuyer’s decision to purchase the Loan is based upon the Buyer’s own independentevaluation.  The Buyer has made suchindependent investigation as the Buyer deems to be warranted into the nature,validity, enforceability, collectibility, and value of the Loan and all otherfacts it deems material to its purchase, and is entering into this transactionherein provided for, solely on the basis of that investigation and the Buyer’sown judgment, and is not acting in reliance on any representation of, orinformation furnished by the Seller and acknowledges that no employee orrepresentative of the Seller has been authorized to make any statements orrepresentations other than those specifically contained in this Agreement.  The Buyer hereby waives any right or cause ofaction it might now or in the future have against the Seller as a result of itspurchase of the Loan.

6.4                                 TheBuyer (i) is able to bear the economic risk associated with the purchase of theLoan, (ii) has adequate information concerning the business and financial conditionof the Borrower or any third party to make an informed decision regarding thepurchase of the Loan, (iii) has such knowledge and experience so as to be awareof the risks and uncertainties inherent in the purchase of rights andassumption of liabilities of the type contemplated in this Agreement and (iv)has independently and without reliance upon the Seller, and based on suchinformation as the Buyer has deemed appropriate, made its own analysis anddecision to enter into this Agreement. The Buyer acknowledges that the Seller has not given the Buyer anyinvestment advice, credit information or opinion on whether the purchase of theLoan is prudent.

6.5                                 TheBuyer has full power and authority to execute, deliver and perform itsobligations under, this Agreement and is authorized to enter into thisAgreement.  All laws, rules andregulations to which the Buyer may be subject have been duly compliedwith.  This Agreement has been duly andvalidly executed and delivered by the Buyer and constitutes the legal, valid,and binding obligation of the Buyer, enforceable against the Buyer inaccordance with its terms, except that such enforceability may be limited bybankruptcy, insolvency, or other similar laws of general applicabilityaffecting the enforcement of creditors’ rights generally and by the court’sdiscretion in relation to equitable remedies.

6.6                                 TheBuyer is an “accredited investor” as that term is defined by the Securities Actof 1933, as amended.  The Buyer has suchknowledge and experience in financial and business matters, relating to theownership and collection of loan assets, that it is capable of evaluating themerits and risks of a prospective investment in the Loan.  The Buyer acknowledges that the Loan may havelimited or no liquidity and it has the financial capability to hold the Loanfor an indefinite period of time and to bear the economic risks of, including acomplete loss of its investment in, the purchase and acquisition of the Loan.

7.                                       **No Recourse or Warranty, Etc.:**  The sale of the Loan is made by the Sellerwithout any representation or warranty either express or implied in fact or bylaw.  Any other provisions of thisAgreement to the contrary notwithstanding, the Seller and the Buyer agree thatno guarantee of any kind or type whatsoever, whether made by public, private orgovernmental entity, is purchased, acquired, assumed, or in any other mannertransferred or conveyed to the Buyer pursuant to this Agreement.  Further, the Seller has not, does not andwill not make any representations or warranties with regard to compliance withany, rules, regulations, orders or requirements.  The Buyer acknowledges and agrees that thesale and assignment of the Loan is made without recourse

3

----

or warranty.  The Seller makes no warranties, covenants orrepresentation of any sort or in any manner with regard to the Loan, exceptthat the Seller is the owner and holder of all rights in the Loan to be soldand assigned and is authorized to consummate such sale by virtue of such rightsand capacity.

8.                                       **Files and Records:**The Buyerfurther agrees as follows:

8.1                                 TheBuyer agrees to abide by all applicable state and federal laws, rules andregulations regarding the handling and maintenance of all documents and recordsrelating to the Loan purchased hereunder including, but not limited to, thelength of time such documents and records are to be retained.

8.2                                 Aftertransfer of documents or files to the Buyer pursuant to the terms of thisAgreement, the Buyer agrees that the Seller shall have the continuing right touse, inspect, and make extracts from or copies of any such documents orrecords, upon the Seller’s reasonable notice to the Buyer.

8.3                                 TheBuyer further agrees to allow the Seller the possession, custody and use oforiginal documents for any lawful purpose and upon reasonable terms andconditions.

8.4                                 Beforedestruction or disposition of any documents or files transferred hereunder, theBuyer agrees to give reasonable notice to the Seller and to allow the Seller,at its own expense, to recover the same from the Buyer.

9.                                       **Notice Of Claim:** The Buyer shall immediately notify the Sellerof any claim, threatened claim, or any litigation against the Seller which maycome to its attention.

10.                                 **Notices**:  Unless otherwise agreed in writing, noticesshall be given to the Seller and the Buyer at their telecopier numbers(confirmed by telephone to their telephone numbers) or addresses set forth inthe signature page of this Agreement, or such other telecopier (and telephone)number or address communicated in writing by either such party to theother.  Notices to the Bank shall beeffective upon receipt.

11.                                 **Use of the Seller Name:**  The Buyer agrees that it will not use orpermit the use****by its agents, successors orassigns, of any name or combination of letters which is similar to “JPMorganChase Bank, N.A.”, “Chase” or “JPMCB.”  The Buyer will not represent or imply that it is affiliated with,authorized by, or in any way related to the Seller.

12.                                 **Severability: **Each part of this Agreement is intendedto be severable.  If any term, covenant,condition or provision hereof is unlawful, invalid, or unenforceable for anyreason whatsoever, such illegality, invalidity, or unenforceability shall notaffect the legality, validity, or enforceability of the remaining parts of thisAgreement, and all such remaining parts hereof shall be valid and enforceableand have full force and effect as if the invalid or unenforceable part had notbeen included.

13.                                 **Construction: **Unless****thecontext otherwise requires, singular nouns and pronouns, when used herein,shall be deemed to include the plural and vice versa, and impersonal pronounsshall be deemed to include the personal pronoun of the appropriate gender.

14.                                 **Assignment: **This Agreement and the terms, covenants,conditions, provision, obligation, undertaking, rights and benefits hereof,shall be binding upon, and shall inure to the benefit of, the undersignedparties and their respective heirs, executors, administrators, representativessuccessors, and assigns.  This Agreementshall not be assigned without the Seller’s prior written consent.

4

----

15.                                 **Prior Understandings: **This Agreement supersedes any and allprior discussions and agreements between the Seller and the Buyer with respectto the purchase of the Loan and other matters contained herein, and thisAgreement contains the sole and entire understanding between the parties heretowith respect to the transactions contemplated herein.

16.                                 **Survival: **Each****and everycovenant made by the Buyer or the Seller in this Agreement shall survive theClosing and shall not merge into the closing documents, but instead shall beindependently enforceable.

17.                                 **Governing Law; Jurisdiction: **ThisAgreement shall be governed by and construed in accordance with the laws of theState of New York.  The Buyer consents tothe nonexclusive jurisdiction and venue of the state or federal courts locatedin such state.  In the event of a disputehereunder, suit may be brought against the Buyer in such courts or in anyjurisdiction where the Buyer or any of its assets may be located.  Service of process by the Seller inconnection with any dispute shall be binding on the Buyer if sent to the Buyerby registered mail at the address(es) specified above or to such furtheraddress(es) as the Buyer may specify to the Seller in writing.

18.                                 **Counterparts:** This Agreement may be executed in any numberof counterparts, all of which taken together shall constitute one and the sameinstrument.

**IN WITNESS WHEREOF**, the Sellerand the Buyer have executed this Agreement by their duly authorized officers asof the date first set forth above.
| **JPMORGAN CHASE BANK, N.A.**                                                                                                      |   |   |   |
|------------------------------------------------------------------------------------------------------------------------------------|--------|--------|--------|
|                                                                                                                               |   |   |   |   |
|                                                                                                                               |   |   |   |   |
| By:                                                                                                                                |   |   |   |   |
|                                                                                                                               | Name:  |   |   |   |
|                                                                                                                               | Title: |   |   |   |
|                                                                                                                               |   |   |   |   |
|                                                                                                                               |   |   |   |   |
| **Address for Notices to the Bank:**                                                                                               |   |   |   |
|                                                                                                                               |   |   |   |   |
| JPMorgan Chase Bank, N.A.  Private Bank Credit  Attn:** **Patricia  DeLeo  345 Park Avenue, Floor 04  New York, NY 10154-0004 |   |   |   |
|                                                                                                                               |   |   |   |   |
| With a courtesy copy to                                                                                                            |   |   |   |
|                                                                                                                               |   |   |   |   |
| JPMorgan Chase Bank, N.A.  Attn:  Nancy A. Sheppard560 Mission Street, 12th floor  San Francisco, CA 94105                    |   |   |   |

 

5

----

 
|                                                                                                                               |                |   |   |
|-------------------------------------------------------------------------------------------------------------------------------|---------------------|--------|--------|
| **Gerald J. Burnett**                                                                                                         |                |   |   |
|                                                                                                                          |                |   |   |   |
|                                                                                                                          |                |   |   |   |
| **Address for notices:**                                                                                                      |                |   |   |
|                                                                                                                          |                |   |   |   |
|                                                                                                                          |                |   |   |   |
| **Gerald J. Burnett and Marjorie J. Burnett , as Trustee for  The Gerald J. Burnett and Marjorie J. Burnett Revocable Trust** |                |
|                                                                                                                          |                |   |   |   |
|                                                                                                                          |                |   |   |   |
| By:                                                                                                                           |                |   |   |   |
|                                                                                                                          | Gerald J. Burnett   |   |   |   |
|                                                                                                                          |                |   |   |   |
|                                                                                                                          |                |   |   |   |
| By:                                                                                                                           |                |   |   |   |
|                                                                                                                          | Marjorie J. Burnett |   |   |   |
|                                                                                                                          |
|                                                                                                                          |
|                                                                                                                          |
| **Address for notices:**                                                                                                      |

 
| State of  | ** ** |   ) |          |   |
|-----------|------------|---------------|---------------|--------|
|      | ** ** | ** **    |   ) | ss.:   |   |
| County of | ** ** |   ) |          |   |

 

On the ____ day of____________ in the year 200__, before me, the undersigned, personally appeared Gerald J. Burnett, personally known to meor proved to me on the basis of satisfactory evidence to be the individualwhose name is subscribed to the within instrument and acknowledged to me thathe/she executed the same in his/her capacity, and that by his/her signature onthe instrument, the individual, or the person upon behalf of which theindividual acted, executed the instrument.
|            | ** ** | ** ** | ** ** |   |          |
|------------|------------|------------|------------|--------|---------------|
| ** ** | ** ** | ** ** | ** ** |   | Notary Public |

 
| State of  | ** ** |   ) |          |   |
|-----------|------------|---------------|---------------|--------|
|      | ** ** | ** **    |   ) | ss.:   |   |
| County of | ** ** |   ) |          |   |

 

On the ____ day of ____________ in the year 200__, before me, theundersigned, personally appeared MarjorieJ. Burnett, personally known to me or proved to me on the basis ofsatisfactory evidence to be the individual whose name is subscribed to thewithin instrument and acknowledged to me that he/she executed the same inhis/her capacity, and that by his/her signature on the instrument, theindividual, or the person upon behalf of which the individual acted, executedthe instrument.

 
|            | ** ** | ** ** | ** ** |   |          |
|------------|------------|------------|------------|--------|---------------|
| ** ** | ** ** | ** ** | ** ** |   | Notary Public |

 

6

----