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                                                          Exhibit 10.19


                          ASSIGNMENT OF PURCHASE ORDER

                              AND SECURITY INTEREST

     This ASSIGNMENT AGREEMENT is made and entered into as of the 10th day of
December, 1999, between Ziplink, Inc. ("Customer") and Alcatel USA Financing,
Inc. ("Assignee".

                                   WITNESSETH:

         WHEREAS, Customer has entered into a Product Purchase and Services
Agreement dated the 29th day of July, 1999 (hereafter referred to as the
"Purchase Agreement"), with Alcatel Internetworking, Inc. (hereafter referred
to as the "Vendor"), whereby the Customer and Vendor have agreed to, among
other things, the terms and conditions upon which the Customer is allowed to
place orders to purchase certain telecommunications hardware and/or license
certain telecommunications software from Vendor; and,

         WHEREAS, pursuant to the terms and conditions of the Purchase
Agreement, the Customer has placed or will from time to time place with
Vendor orders under such Purchase Agreement which may be attached to this
Agreement as Exhibits and which (whether or not attached to this Agreement as
Exhibits) are hereby incorporated by reference (collectively, the "Order").
The hardware and license of software so described in the Order shall
hereinafter be collectively referred to as the "Equipment"); and,

         WHEREAS, Assignee and Customer have entered into or propose to enter
into an Equipment Lease (the "Lease"), pursuant to which Assignee proposes,
subject to the terms and conditions hereof and of the Lease, to acquire the
Equipment and lease and/or license it to Customer; and as a condition to
entering into the Lease and in order to enable Assignee to acquire the Equipment
(and in the case of any software constituting a portion of the Equipment, the
license to use such software), it is necessary that this Assignment be executed;

         NOW THEREFORE, in consideration of the foregoing, Customer hereby
sells, assigns and transfers to Assignee all of Customer's right, title and
interest in and to the Order (but not its obligations thereunder except to pay
the purchase price therefor upon delivery by the Vendor to the Customer and
acceptance by Assignee of a Certificate of Acceptance (defined below) executed
by Customer under the Lease with respect to the Equipment), including, without
limitation, the right to take title to the Equipment and to be named as
purchaser in any bills of sale or invoices to be delivered by Vendor, this
Assignment being subject, however, to the following conditions:

         1. This Assignment shall not become effective with respect to any
Equipment prior to the date upon which Customer executes and delivers to
Assignee and Assignee accepts a Certificate of Acceptance of Equipment (a
"Certificate of Acceptance") relating to such Equipment in form satisfactory to
Assignee.

         2. By accepting delivery of a signed copy of this Assignment, Assignee
agrees that, notwithstanding this Assignment, at all times prior to the
acceptance by Assignee of a Certificate of Acceptance executed by Customer
relating to any Equipment that has not become subject to the Lease, Customer may
continue to exercise, with respect to any Equipment covered by an Order, all
rights of the buyer under the Purchase Agreement, and Vendor may continue to
deal, with respect to such Order and related Equipment, solely with Customer for
all of the purposes of the Purchase Agreement in all respects as if this
Assignment had not been executed.

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         3. Except as otherwise expressly provided, the rights and obligations
of Vendor and Customer under the Purchase Agreement, shall remain in effect.
Without limiting the generality of the foregoing, Vendor's warranty and support
obligations under the Purchase Agreement shall continue in full force and effect
and Customer, as lessee of the Equipment, shall enforce such obligations
directly against Vendor all in accordance with the provisions of the Purchase
Agreement and the Lease so long as no default shall have occurred under the
Lease (in which case such warranties, upon notice by Assignee to the Vendor,
shall revert to the Assignee). Customer agrees that Assignee has not and does
not by virtue of this Assignment assume any of Customer's obligations or
liabilities (other than to pay the purchase price of the Equipment to Vendor as
expressly provided herein), and that Assignee shall not have any obligation or
liability under the Purchase Agreement (or with respect to the Equipment) or be
obligated to perform any of the obligations or duties of Customer thereunder or
related thereto, whether arising prior to or on or after the date of this
Assignment, and Customer shall at all times remain obligated and liable to
Vendor under the Purchase Agreement as if this Assignment had not been executed.

         4. Customer agrees that at any time and from time to time, upon the
written request of Assignee, Customer shall promptly and duly execute and
deliver any and all such further instruments and documents, and take such
further action as Assignee may request in order to obtain the full benefits of
this Assignment.

         5. Customer represents and warrants that the Purchase Agreement is in
full force and effect and is enforceable in accordance with its terms, and that
Customer is not in default thereunder. Customer further represents, warrants and
covenants that it will not assign or pledge, so long as this Assignment remains
in effect, the whole or any part of the rights hereby assigned, to anyone other
than Assignee.

         6. Notwithstanding the foregoing, it is understood and agreed, that
until a default shall have occurred under the Lease, all rights and claims under
any guaranty or warranty, express or implied, with respect to the Equipment or
any item of Equipment, shall be enforced by Customer, subject to the terms of
the Lease, at its sole cost and expense either in its own name or in the name of
Assignee; provided, however, that no action shall be brought in Assignee's name
without Assignee's written consent, and in any event Customer agrees to
indemnify Assignee against and save it harmless from all costs and expenses
arising out of any action or proceedings which Customer may bring against
Vendor. This indemnity shall survive the earlier termination of this Assignment
and the Lease. Customer agrees to preserve and protect the Assignee's rights
under any warranty, covenant or representation made by the Vendor with respect
to the Equipment, and Customer warrants that Customer will not take any action
which will impair such rights of Assignee, and covenants to act solely in
compliance with any restrictions and requirements prerequisite to the continued
existence, enforcement, validity and maintenance of any warranty, covenant or
representation.

         7. Customer agrees that it will not modify or amend the Purchase
Agreement or permit any waiver with respect thereto without the prior written
consent of Assignee.

          8. The execution of this Assignment by Customer and the acceptance
thereof by Assignee shall not constitute a commitment by Assignee to enter into
the Lease or to lease any Equipment to Customer unless and until a duly
authorized officer of Assignee shall have executed and accepted the Lease and
returned an executed copy thereof to Customer. Assignee's obligation to lease
any Equipment to Customer is subject to the further conditions (the "CONDITIONS
PRECEDENT") that Customer shall not be in default under any of the terms of
conditions of the Lease; that the Certificate of Acceptance with respect to such
Equipment shall have been executed and delivered to Assignee by Customer and
accepted by Assignee; that there shall have been no

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material adverse change in the business or financial condition of Customer; and
that all matters incident to the transactions contemplated by the Lease and any
Schedule thereto are satisfactory to Assignee and Assignee's counsel.
Notwithstanding any execution and acceptance of the Lease by Assignee, Assignee
shall not be responsible for Vendor's failure to honor this Assignment, to
perform under the Purchase Agreement or to deliver any Equipment in accordance
with the terms thereof.

         9. Nothing contained herein shall: (a) subject the Vendor to any
liability to which it would not otherwise be subject under the Purchase
Agreement; or (b) modify in any respect the contract rights of the Vendor under
the Purchase Agreement, except as provided in the Consent Agreement hereto.

         10. Assignee hereby accepts the assignment herein contained. Assignee
agrees, solely for the benefit of Customer, so long as the Conditions Precedent
set forth in Section 8 above for the lease of the Equipment have been satisfied,
to purchase the Equipment from the Vendor and to take such title to the
Equipment as is conveyed to it; provided, however, that Assignee shall not be
obligated to pay for any Equipment until the Conditions Precedent set forth in
Section 8 for the lease of such Equipment have been satisfied (including without
limitation that Assignee has accepted a Certificate of Acceptance executed and
delivered by Customer with respect to such Equipment, as provided for herein),
and Customer shall remain fully liable therefor.

         11. Vendor hereby assigns, transfers and conveys to Assignee the
security interest in the Equipment granted to Vendor pursuant to the Purchase
Agreement. Vendor, Assignee and Customer agree to take all reasonable actions
necessary to effect, protect and perfect such assignment, transfer or conveyance
as reasonably requested by any of them. All fees, charges or taxes required to
be paid by Assignee to record the security interest assigned herein shall be
paid by Customer upon invoice.

         12. THIS ASSIGNMENT SHALL BE GOVERNED BY THE LAWS OF THE STATE OF
TEXAS, and may be modified only by a written amendment signed by all parties.
Any action or claim to enforce the provisions of this Assignment may be brought
in the appropriate state or federal district court in the State of Texas. The
Lessee irrevocably consents to service of process in accordance with the
provisions of the laws of the State of Texas and waives any right to object to
the laying of venue in any state or federal court in the State of Texas.

     ASSIGNEE:                                  CUSTOMER:

     ALCATEL USA FINANCING, INC.                ZIPLINK, INC.

     By:     /S/ RONALD R. FUQUA                By:      /S/ GARY P. STRICKLAND

     Title: TREASURER AND SENIOR DIRECTOR       Title: CHIEF FINANCIAL OFFICER

 Attachment -- Consent and Agreement of Alcatel Internetworking, Inc.