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                                                                   Exhibit 10.5B

                            APPLIED INNOVATIONS INC.

                              EMPLOYMENT AGREEMENT
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     This Agreement is made this 5th day of May, 1997, by and between
William H. Largent and APPLIED INNOVATION INC., a Delaware corporation with its
principal office at 5800 Innovation Drive, Dublin, Ohio 43016, its affiliated,
subsidiaries, successors and assigns (the "Company").

                                    WHEREAS

     The company is engaged in the business of developing, manufacturing and
marketing data communications equipment, internet access devices, software and
services to telephone companies, interexchange telephone carriers, cable
television companies, and electric utilities, for alarm data communications,
network mediation and management, interoperability of networks, and network
switching and routing, and develops and uses valuable technical and
nontechnical trade secrets and other confidential information which it desires
to protect.

     The Company invests considerable resources in recruiting, training and
developing employees to perform specialized services and fill individualized
customer needs in a highly competitive market. The Company has also invested
extensive resources in developing and retaining its major customers and its
contacts with key employees of its major customers.

     You desire to be employed by the Company in a position of trust and
confidence in which you may receive or contribute to the confidential
information of the Company.

     The Company desires to maximize your effectiveness and professional
growth by allowing you access to its trade secrets and confidential
information, but at the same time wishes to ensure that you exert your
full-time best efforts on behalf of the Company, except as provided herein, and
to ensure that the Company's trade secret and confidential information is
maintained in confidence and used only for the benefit of the Company and not
for the purpose of competition with the Company.

     THEREFORE, the parties agree as follows:

     1.   CONSIDERATION. The Company shall employ you and provide you with
access to certain Confidential Information as defined in this Agreement and
other valuable consideration.

     2.   RESTRICTED EMPLOYMENT. While employed by the Company, you shall
devote your best efforts to the business of the Company and shall not engage in
any outside employment or consulting work without first securing the written
consent of the Company. The Company acknowledges that you presently serve as a
director of Amerilink Corp., Maximation incorporated, and BellePointe, Inc. and
you may continue in these outside director positions if you choose, so long as
such time commitments do not interfere with your responsibilities at the
Company. You will, of course be permitted to hold totally passive business


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investments and take part in community, civic, or charitable activities that
neither interfere with nor are inconsistent with your responsibilities to the
Company.

     3.   CONFIDENTIAL INFORMATION.

          a.   As used throughout this Agreement, the term "Confidential
Information" means any information you acquire during employment by the Company
(including information you conceive, discover or develop) which is not readily
available to the general public and which relates to the business, including
research and development projects, of the Company, its subsidiaries or its
affiliated companies.

          b.   Confidential Information includes without limitation,
information of a technical nature (such as secrets, inventions, discoveries,
product requirements, designs, software codes and manufacturing methods),
matters of a business nature (such as customer lists, the identities of
customer contacts, information about customer requirements and preferences, the
terms of the Company's contracts with its customers and suppliers, and the
Company's costs and prices), personnel information (such as the identities,
duties, customer contacts, and skills of the Company's employees) and other
financial information relating to the Company and its customers (including
credit terms, methods of conducting business, computer systems, computer
software, personnel data, and strategic marketing, sales or other business
plans). Confidential Information may or may not be patentable.

          c.   Confidential information does not include information which you
learned prior to employment with the Company from sources other than the
Company, information you develop after employment from sources other than the
Company's Confidential Information or information which is readily available to
persons with equivalent skills, training and experience in the same field or
fields of endeavor as you. You must presume that all information that is
disclosed or made accessible to you during employment by the Company is
Confidential Information if you have a reasonable basis to believe the
information in Confidential Information or if you have notice that the Company
treats the information as Confidential Information.

     4.   CONFIDENTIALITY.
          a.   Except in furtherance of the Company's business, you shall not
at any time, either during or for five years following employment with the
Company, make use of, or disclose to any other person or entity, any
Confidential Information unless (i) the specific information becomes public
from a source other than you or another person or entity that owes a duty of
confidentiality to the Company and (ii) twelve months have passed since the
specific information became public. However, you may discuss Confidential
Information with employees of the Company when necessary to perform your duties
to the Company.

          b.   Upon Employment Separation, you shall deliver to the Company all
copies, notes, documents or records of any kind that relate to any Confidential
Information. As used herein, the term "notes" means written or printed words,
symbols, pictures, numbers or formulae. As used throughout this Agreement, the
term "Employment Separation" means the separation and/or termination of your
employment with the Company, regardless of the time, manner or cause of such
separation or termination.


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     5.   INVENTIONS.

          a.   As used throughout this Agreement, the term "Inventions" means
any inventions, improvements, designs, plans, discoveries or innovations of a
technical or business nature, whether patentable or not, relating in any way to
the Company's business or contemplated business if the Invention is conceived
or reduced to practice by you during your employment by the Company. Inventions
includes all data, records, physical embodiments and intellectual property
pertaining thereto. Inventions reduced to practice within one year following
Employment Separation shall be presumed to have been conceived during
employment.

          b.   Inventions are the Company's exclusive property and shall be
promptly disclosed and assigned to the Company without additional compensation
of any kind. If requested by the Company, you, your heirs, your executors, your
administrators or legal representative will provide any information, documents,
testimony or other assistance needed for the Company to acquire, maintain,
perfect or exercise any form of legal protection that the Company desires in
connection with an Invention.

          c.   Upon Employment Separation, you shall deliver to the Company all
copies of and all notes with respect to all documents or records of any kind
that relate to any Inventions.

     6.   COVENANT NOT TO COMPETE.

          a.   You acknowledge that the Confidential Information has been and
will be developed and acquired by the Company by means of substantial expense
and effort, that the Confidential Information is a valuable asset of the
Company's business, that the disclosure of the Confidential Information to any
of the Company's competitors would cause substantial and irreparable injury to
the Company's business, and that any customers of the Company developed by you
or others during your employment are developed on behalf of the Company. You
further acknowledge that you have been provided with access to Confidential
Information, including Confidential Information concerning the Company's major
customers, and its technical, marketing and business plans, disclosure or
misuse of which would irreparably injure the Company.

          b.   During employment by the Company and for a period of 12 months
following Employment Separation, you shall not (as an owner, shareholder,
officer, employee, manager, consultant or otherwise):

          (i)     Contact any employee of the Company for the purpose of
      discussing or suggesting that such employee resign from employment with
      the Company for the purpose of becoming employed elsewhere;

          (ii)    Provide information about individual employees of the Company
      or personnel policies or procedures of the Company to any person or
      entity, including any individual, agency or company engaged in the
      business of recruiting employees, executives or officers; or



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          (iii)   If you served as an officer of the Company and/or performed
      any duties involving sales, marketing, sales engineering and/or product
      line management in the twelve months preceding Employment Separation, you
      shall not promote, solicit for sale or sell any product or service in
      direct competition with the Company's products or services (A) to any
      entity that purchased over $250,000 in goods and/or services from the
      Company during the 12 months preceding Employment Separation, (B) to any
      entity which you called on for the purpose of promoting or selling the
      Company's products or services during the 12 months preceding Employment
      Separation, or (C) to any entity which received a sales proposal from the
      Company within 12 months of Employment Separation if the goods or services
      which you seek to sell, solicit for sale or promote are directly
      competitive with the goods and services which are the subject of the
      Company's proposal to the entity and the entity has not yet rejected the
      Company's sales proposal.

          c.   The 12-month non-competition period described in Section 6(b) of
this Agreement shall be suspended while you engage in any activities in breach
of the Agreement. In the event that a court grants injunctive relief to the
Company for your failure to comply with Section 6, the non-competition period
shall begin again on the date such injunctive relief is granted.

          d.   Nothing contained in the Section 6 shall be construed as
limiting your obligations under Section 3 or 4 or this Agreement concerning
Confidential Information and Confidentiality.

     7.   REMEDIES. Without limiting any of the Company's other remedies, you
agree that, in the event you fail to comply with this Agreement in any way, the
Company shall be entitled to injunctive relief against you to enforce your
obligations under this Agreement and you shall reimburse the Company for it
reasonable expenses, including attorneys' fees, incurred in seeking to enforce
this Agreement. If the Company seeks to enforce its rights under this Agreement
in a court and is denied any relief, the Company shall reimburse you for your
reasonable expenses, including attorneys' fees, in defense of that court action.

     8.   EXIT INTERVIEW. Prior to Employment Separation, you shall attend an
exit interview if desired by the Company and shall, in any event, inform the
Company at the earliest possible time of the identity of your future employer
and of the nature of your future employment.

     9.   NO WAIVER. Any failure by the Company to enforce any provision of
this Agreement shall not in any way affect the Company's right to enforce such
provision or any other provision at a later time.

     10.  SAVING. If any provision of this Agreement is later found to be
completely or partially unenforceable, the remaining part of that provision of
any other provision of this Agreement shall still be valid and shall not in any
way be affected by the finding. Moreover, if any provision is for any reason
held to be excessively broad as to time, duration, geographical scope,
activity or subject, such provision shall be interpreted by limiting and
reducing it to preserve enforceability to the maximum extent permitted by law.


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     11.  EMPLOYMENT AT WILL; NO LIMITATION. You acknowledge that your
employment by the Company is at-will and that your employment may be terminated
at any time by the Company or you with or without cause. This Agreement is in
addition to and not in place of other obligations of trust, confidence and
ethical duty imposed on you by law.

     12.  GOVERNING LAW. This Agreement shall be interpreted and enforced in
accordance with the laws of the State of Ohio without reference to its choice
of law rules.

     13.  FINAL AGREEMENT. This Agreement replaces any existing agreement
between you and the Company relating to the same subject matter and may be
modified only by an agreement in writing signed by both you and a duly
authorized representative of the Company.

     14.  FURTHER ACKNOWLEDGMENTS. YOU ACKNOWLEDGE THAT YOU HAVE RECEIVED A
COPY OF THIS AGREEMENT, THAT YOU HAVE READ AND UNDERSTOOD THIS AGREEMENT, THAT
YOU UNDERSTAND THIS AGREEMENT AFFECTS YOUR RIGHTS, AND THAT YOU HAVE ENTERED
INTO THIS AGREEMENT VOLUNTARILY.


                                   APPLIED INNOVATION INC.

                                   By: /s/ Virginia J. Stanley
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                                   Printed:
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                                   Its:
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                                   EMPLOYEE:

                                   Signed: /s/ William H. Largent
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                                   Printed:  William H. Largent
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