<PAGE>   1
                                                                    EXHIBIT 10.5



MASTER AGREEMENT for INTERNETWORKING SERVICES

GTE Internetworking
Powered by BBN

This Master Agreement between GTE Internetworking Incorporated ("We") and the
Customer identified below ("You") includes the attached Service Schedules and
Service Quotations (collectively "Schedules") together with any additional
Schedules mutually agreed in writing in the future.

1. Services. We will provide you the Internetworking services ("Services")
specified in the Schedule(s). Our commencement of providing any of the Services
shall constitute our acceptance of this Master Agreement.

2. Prices. Prices are stated in the Schedules and are guaranteed for the Term
stated in the Schedules. If any of the Services are on a month-to-month basis,
we will give you at least 30 days notice of a price change. In addition, you are
responsible for applicable taxes, tariffs, telecommunications surcharges or
other governmental charges due on account of Services.

3. Payment. Unless otherwise stated in a Schedule, we will invoice you monthly.
You agree to pay within 30 days from receipt of invoice. For overdue invoices,
you will pay interest of 1.5% for each month or part of a month (or the maximum
allowed by law, whichever is less).

4. Our Responsibility. We are responsible for proving the Services by qualified
personnel in a professional manner. WE DISCLAIM ALL OTHER WARRANTIES, EXPRESS OR
IMPLIED, INCLUDING THE WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A
PARTICULAR PURPOSE.

5. Your Responsibility.  You are responsible for the manner in which you use


<PAGE>   2
your services, including the maintenance and security of your data, computer
network and other facilities; your choice of equipment, software and online
content; and all other matters related to how you use the Services. Unless
expressly permitted by a Schedule or separate reseller agreement with us, you
shall not resell Services, or access to Services, directly or indirectly to
third parties.

6. Indemnification. We will indemnify you for damages, cost, and attorneys fees
you incur from any claim that our design of the Services infringes any U.S.
patent, copyright, trademark, trade secret or other intellectual property right.
You will indemnify us for damages, cost and attorneys fees we incur from any
claim arising from your manner of using of the services, your combination of
services with other products or services not provided by us, or your
modification of the Services. The indemnifying party shall conduct the defense
and shall have control of the litigation; the other party shall give prompt
notice of claims and shall cooperate in the defending against the claim. THE
PARTIES DISCLAIM THE IMPLIED WARRANTY OF NON-INFRINGEMENT, RELYING INSTEAD ON
THE TERMS OF THIS SECTION.

7. IP Addresses. Upon expiration, cancellation or termination of the Agreement
or applicable Schedule, you shall relinquish any IP addresses or address blocks
assigned to you by us.

8. Compliance with Laws. You shall not use or permit your end users to use the
Services in ways that violate laws, infringe the rights of others, or interfere
with users of our network or other networks. For example, you shall not
distribute chain letters or unsolicited bulk electronic mail ("spamming");
propagate computer worms or viruses; use a false identity; attempt to gain
unauthorized entry into any site or network; distribute child pornography,
obscenity or defamatory material over the Internet; or infringe copyrights,
trademarks or other intellectual property rights. You further agree to comply
with U.S. export laws concerning the transmission of technical data and other
regulated materials via the Services.

9. Termination. Either party may terminate or cancel this Agreement if the other
fails to cure material breach of the Agreement within 30 days after receiving
written notice of the breach. We reserve the right, but assume no obligation, to
suspend performance immediately if you are more than 30 days overdue in payments
or if, our reasonable judgement, you have violated Section 8.

10. Limitation of Liability.  EXCEPT FOR INDEMNIFICATION PURSUANT TO SECTION 6,
NEITHER PARTY (NOR ITS SUPPLIERS OR CUSTOMERS) SHALL BE LIABLE TO THE OTHER
PARTY FOR PUNITIVE, SPECIAL, CONSEQUENTIAL, INCIDENTAL OR INDIRECT DAMAGES
INCLUDING WITHOUT LIMITATION, LOST PROFITS OR LOSS OR DAMAGE TO DATA ARISING OUT
OF THE USE OR INABILITY TO USE SERVICES, EVEN IF THE PARTY HAS BEEN ADVISED OF
THE POSSIBILITY OF SUCH DAMAGES.

11. Limitation of Damages. OUR AGGREGATE LIABILITY TO YOU RELATING TO OR ARISING
OUT OF THIS AGREEMENT, WHETHER IN CONTRACT, TORT OR OTHERWISE, SHALL NOT EXCEED
(a) THE TOTAL AMOUNTS PAID BY YOU TO US FOR THE SERVICE IN QUESTION, DURING THE
ONE-YEAR PERIOD IMMEDIATELY PRECEDING THE EVENT WHICH GAVE RISE TO YOUR CLAIMS
OR (b) $100,000, WHICHEVER IS LESS.

12. Acknowledgement. You agree that we may include your name in listings of our
customers.

13. Miscellaneous. The terms and conditions of this Agreement supersede all
previous agreements, proposals or representations related to the Services.
Except for assignments to GTE affiliates, neither party may assign this
Agreement without the prior written consent of the other party. This Agreement
shall be governed by the substantive laws of the Commonwealth of Massachusetts.
Any changes to this Agreement, or any additional or different terms in your
purchase orders, acknowledgements, or other documents, will not be effective
unless expressly agreed to in writing to us.

Customer:    Micro-Media Solutions, Inc.

Signature:   /s/ Mitchell Kettrick V. P.   Date:  5-29-98

Print Name:  Mitchell Kettrick V. P.       Title: Vice-president

<PAGE>   3