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                   JOINT MARKETING AND DISTRIBUTION AGREEMENT


         This JOINT MARKETING AND DISTRIBUTION AGREEMENT ("Agreement") is
executed as of June 25, 1999, by and between CONCENTRIC NETWORK CORPORATION
("Concentric"), a Delaware corporation with its principal offices at 1400
Parkmoor Avenue, San Jose, CA 95126, and register.com, Inc. ("register.com"), a
Delaware corporation with its principal offices at 575 Eighth Avenue, 11th
Floor, New York, NY 10018. Concentric and register.com, and their respective
successors and permitted assigns, are sometimes individually referred to herein
as a "Party" or collectively as the "Parties."

                                    RECITALS

         WHEREAS, Concentric currently supplies Internet access, web hosting,
e-commerce and domain name registration services to consumers and business
customers;

         WHEREAS, register.com currently provides domain name registration,
e-mail and web hosting services to consumers and business customers, and sells
advertising space to companies interested in reaching visitors to web sites
owned and operated by register.com;

         WHEREAS, Concentric and register.com desire to enter into an agreement
to offer certain Concentric web hosting and e-commerce services to
register.com's customers, to make register.com's domain registration services
available to Concentric's web hosting customers and OEM partners, and to
cooperate in certain other business opportunities that may further the interests
of both Parties;

         WHEREAS, Concentric has agreed to invest (the "Investment") $5 million
in register.com by participating in register.com's current round of venture
capital financing, which is currently expected to close on or about June 25
under the terms set forth in that Letter of Intent, dated June 2, 1999 between
Sandler Capital Partners IV, L.P., Sandler Capital Partners IV FTE, L.P. and
register.com.

         NOW, THEREFORE, in consideration of the promises, conditions and mutual
covenants set forth below, the adequacy of which is hereby acknowledged, the
Parties agree as follows:

                                    AGREEMENT

1. DEFINITIONS

   1.1.   "Web Hosting" shall mean the hosting of Internet web sites for
          customers on a web server dedicated to a given customer or on one or
          more web servers shared among multiple customers. Web Hosting shall
          not mean any e-commerce services except for E-Commerce (as defined in
          Section 1.2 below).

   1.2.   "E-Commerce" shall mean any product catalog, shopping cart and/or
          transaction processing server-side technology closely integrated
          together and sold solely in connection with Web Hosting services.

   1.3.   "Private Label" shall mean services that are provided by a Party but
          marketed and sold under a name and product brand that is not owned or
          controlled by such Party.

   1.4.   "Domain Registration" shall mean the process through which a unique
          Internet domain name is selected and submitted to a designated domain
          name registry.

   1.5.   "DNS" shall mean Domain Name Server, the primary database with which a
          given registered domain name is associated.

   1.6.   "Web Properties" shall mean any and all publicly available Internet
          web sites located at the domain "register.com", or any other domain
          owned, operated and maintained by register.com, or its successors or
          assigns, in each case used for Domain Registration.


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   1.7.   "Concentric Offers" shall mean advertising and promotional materials
          that are presented to potential customers that may be interested in
          purchasing Web Hosting and/or E-Commerce services.

   1.8.   "Net New Registrant" shall mean a completed Domain Registration
          including payment for the newly registered domain name.

   1.9.   "Concentric Opportunities" shall mean Net New Registrants made
          available to Concentric solely for the benefit of Concentric and
          solely for Web Hosting and/or E-Commerce opportunities.

   1.10.  "Above the Fold" shall mean Internet web site content that is visible
          in its entirety above the bottom edge of the browser window when a
          standard 800x600 computer display is employed.

   1.11.  "Net Registration Revenue" shall pertain only to gTLD Names and shall
          mean the amount charged customers for Domain Registration less the
          amount paid to third party domain registries, less other expenses
          directly and solely attributable to functioning as a designated domain
          name registrar or reseller, less industry and regulatory fees, and
          less any applicable taxes (excluding any income tax paid by
          register.com).

   1.12.  "gTLD Names" shall mean only those domain names registered under the
          generic top level domains of .com, .net, and .org.

   1.13.  "Joint Customer" shall mean a Net New Registrant that purchases Web
          Hosting or E-Commerce services from Concentric.

2. MARKETING OF CONCENTRIC SERVICES

   2.1.   Limited Exclusivity. During the Term (as defined in Section 6.1.5
          below), Concentric shall be one (1) of no more than three (3)
          Web-Hosting or E-Commerce service providers that are marketed,
          advertised, or otherwise promoted on the Web Properties. The
          appearance of all Concentric Offers referred to throughout this
          Agreement shall have an appearance, size, and placement, taken as
          whole, no less favorable in all material respect than any other Web
          Hosting or E-commerce service provider present on the Web Properties.
          In the event of any conflict between the immediately preceding
          sentence and the terms and conditions of Sections 2.2 and 2.3,
          Sections 2.2 and 2.3 shall govern.

   2.2.   Placement. During the Term, Concentric Offers shall receive prominent
          placement on the Web Properties. The content of the Concentric Offers
          shall be at Concentric's sole cost and expense and shall be subject to
          the prior approval of register.com, which approval shall not be
          unreasonably withheld. The placement of the Concentric Offers on the
          Web Properties shall be subject to the conditions set forth in
          Sections 2.2.1 to 2.2.4 below.

          2.2.1. Concentric Offers shall be presented Above the Fold for those
                 customers selecting the "Business Resources" or the "Web
                 Hosting" buttons on the navigation toolbar used throughout the
                 Web Properties and reproduced in Exhibit A and on the
                 "FutureSite" page reproduced in Exhibit B. Register.com will
                 ensure that end-users receive an aggregate total of no less
                 than 8,000,000 impressions per month of the "Business
                 Resources" and "Web Hosting" buttons. In no case will the
                 Concentric Offers be more than one (1) hyperlink away from any
                 "Business Resources" or "Web Hosting" button presented on the
                 Web Properties.

          2.2.2. Concentric Offers shall be presented via banner advertisements
                 throughout the Web Properties. Register.com will ensure that
                 end-users will receive an aggregate total of no less than
                 250,000 Above the Fold impressions per month of the banner
                 advertisements. These banner advertisements will hyperlink
                 directly to a URL owned, operated and maintained by Concentric.

          2.2.3. Concentric Offers shall be made prominently visible to the
                 guaranteed minimum number of Concentric Opportunities as set
                 forth in Exhibit C. Concentric Offers shall at no time during
                 the Term be presented to less than one-third (33.3%) of Net New
                 Registrants. The Concentric Offers relevant to this Section
                 2.2.3 shall hyperlink directly to a URL owned, operated, and
                 maintained by Concentric.


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2.2.4. Notwithstanding the forgoing, Concentric shall receive placement
throughout the Web Properties no less favorable than the placement received by
any other Web Hosting or E-commerce service provider.

   2.3.   Web Site Content. Content of the Concentric Offers shall comply with
          the register.com Advertising Guidelines set forth in Exhibit F.
          Concentric and register.com acknowledge the goal of converting at
          least 5% of Concentric Opportunities into Web Hosting and/or
          E-Commerce customers and will use commercially reasonable efforts to
          cooperate to improve the Domain Registration process such that this
          goal can be achieved. However, at no time will register.com be
          required to change the Domain Registration process to the commercial
          detriment of its business nor required to obtain or maintain a 5%
          conversion rate for the Concentric Opportunities. Notwithstanding the
          foregoing, the following efforts shall be undertaken:

          2.3.1. After the Launch Date (as defined in Section 6.1.2),
                 register.com shall present to new domain name registrants on
                 the Web Properties a survey that has been amended to include an
                 offer to each prospective customer during the Term to receive
                 additional information on Web Hosting and E-Commerce services.

          2.3.2. During the Term, register.com will place banner advertisements
                 for Concentric Offers Above the Fold on no less than 75% of
                 register.com's Domain Registration web pages.

          2.3.3. For thirty (30) days following the Launch Date, the last page
                 of the register.com Domain Registration process shall be in
                 form and content substantially similar to the layout described
                 in Exhibit E and shall include a Concentric Offer. A display of
                 this Concentric Offer to a Net New Registrant will constitute
                 the creation of a Concentric Opportunity. Following the
                 expiration of the initial thirty-day period following the
                 Launch Date, the obligations of Section 2.3.4 below shall
                 prevail.

          2.3.4. Within thirty (30) days of the Launch Date, Concentric and
                 register.com shall jointly determine if modifications to the
                 last page of the Domain Registration process will be necessary
                 in order to help achieve the targeted 5% conversion rate
                 described in Section 2.3 above. In addition, at least once
                 during each ninety (90) day period during the Term,
                 register.com shall consider, in good faith, recommendations by
                 Concentric to modify the last page of the register.com Domain
                 Registration process. If during the Term register.com and
                 Concentric identify mutually agreeable changes to the last page
                 of the Domain Registration process, then register.com shall
                 implement such changes within ten (10) business days of their
                 mutual agreement. If at any time during the Term register.com
                 and Concentric cannot reach mutual agreement on the form and
                 content of the last page of the Domain Registration process,
                 then the version of such page that was most recently mutually
                 agreeable shall be presented to Net New Registrants and
                 register.com and Concentric shall continue to negotiate in good
                 faith until mutual agreement can be reached.

          2.3.5. During the Term, register.com shall consider in good faith
                 recommendations by Concentric with respect to the Domain
                 Registration process, with the objective of improving the Web
                 Hosting services purchase rate for Net New Registrants.

   2.4.   Marketing Rights. Register.com shall provide to Concentric all
          relevant collected information on "Concentric Targets." The parties
          shall determine a mutually agreeable list of relevant information that
          shall be provided to Concentric by register.com. For the purposes of
          this Section 2.4, "Concentric Targets" shall mean at least one-third
          (33.3%)of end-users that (a) complete the survey described in Section
          2.3.1 and (b) either (1) indicate an interest in receiving additional
          information on Web Hosting and E-Commerce services or (2) do not
          object to their names being provided to third party organizations for
          the purposes of marketing. Register.com shall deliver such customer
          information on Concentric Targets within a commercially reasonable
          period following presentation of a Concentric Offer to the Net New
          Registrant at the end of the Domain Registration process. Register.com
          acknowledges the goal of providing Concentric with such information on
          Concentric Targets in real-time or near real-time. Concentric may, at
          its sole discretion, contact Concentric Targets for the purposes of
          selling and marketing its services. Concentric will not resell or
          distribute the information on Concentric Targets to any third parties
          or use such information in violation of any applicable law.


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   2.5.   Customer Ownership. Upon a Joint Customer's purchase of Web Hosting or
          E-commerce services, Concentric may, at it's sole discretion, require
          that the domain for that Joint Customer be transferred from
          register.com's DNS to Concentric's DNS. The following obligations
          regarding Joint Customers shall apply:

          2.5.1. At no time shall register.com intentionally contact a Joint
                 Customer for the purposes of marketing or selling Web Hosting
                 or E-commerce services, nor shall register.com sell or
                 otherwise distribute information on a Joint Customer to
                 companies that register.com knows to be engaged, directly or
                 indirectly, in marketing or selling Web Hosting or E-Commerce
                 services.

          2.5.2. Notwithstanding the restrictions created in Section 2.5.1,
                 register.com may distribute information on a Joint Customer to
                 either of the two (2) other Web Hosting and E-commerce service
                 providers allowable under this Agreement if and only if the
                 Joint Customer is not presented a Concentric Offer after the
                 completion of another Domain Registration process.

          2.5.3. If and when register.com has developed and deployed the
                 technology, systems and processes to suppress the presentation
                 of competing Web Hosting or E-commerce offers to Joint
                 Customers, the rights granted to register.com under Section
                 2.5.2 shall be terminated.

          2.5.4. Should register.com discover that it has unintentionally
                 contacted a Joint Customer or unknowingly distributed
                 information on a Joint Customer in violation of Section 2.5.1,
                 register.com shall inform Concentric within ten (10) days of
                 such contact or distribution.

          2.5.5. Concentric and register.com shall meet no less than quarterly
                 during the Term to determine and implement a mutually agreeable
                 plan for marketing to Joint Customers services that do not fall
                 under the definitions of Domain Registration, Web Hosting, or
                 E-commerce provided in this Agreement.

   2.6.   Market Development Funds. During the Initial Term (as defined in
          Section 6.1.3 below), register.com shall pay to Concentric a market
          development fund in the amount of $41,666.67 per month to be spent by
          Concentric for co-branded marketing programs designed and implemented
          by Concentric and approved by register.com, which approval shall not
          be unreasonably withheld or delayed, to increase the size of the
          market for Domain Registration, Web Hosting and E-Commerce services.
          To the extent that either Concentric or register.com are able to
          track, in a mutually agreeable manner, the leads created by the
          co-branded marketing programs, such leads shall be counted toward the
          guaranteed minimum Concentric Opportunities as per Section 2.8.
          Concentric and register.com will use reasonable efforts to track such
          leads. Such amount shall be paid to Concentric by register.com on the
          fifteenth day of every month during the Initial Term following
          Concentric's delivery of an invoice. If such payment is not made
          timely, register.com will pay a late fee equal to 1.5% for each month
          or portion thereof until all past-due obligations are paid. Within
          fifteen (15) days of the Effective Date(as defined in Section 6.1.1
          below), Concentric and register.com shall agree in writing as to the
          form of the co-branded marketing programs that shall benefit both
          Parties in an equitable manner. As requested in writing by
          register.com no more than once per month during the Term, Concentric
          shall provide to register.com evidence that demonstrates that the
          market development fund is being spent by Concentric in accordance
          with the co-branded marketing programs described in the previous
          sentence.

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   2.7.   Integration Requirements. By the Launch Date, Concentric and
          register.com shall have completed the integration of the register.com
          Web Properties and Domain Registration process with the Concentric Web
          Hosting and E-commerce services such that all obligations of this
          Section 2 can be fulfilled. This integration shall include, but shall
          not be limited to, (a) methods to transfer domains from register.com's
          DNS to Concentric's DNS in a timely and mechanized manner should
          Concentric decide, in its sole discretion, to require such a transfer
          and (b) methods to ensure the timely transfer of customer information
          as required by Section 2.4.

   2.8.   Performance. During the first month of the Initial Term, register.com
          will ensure that at least 16,667 Concentric Opportunities are created.
          The sole evidence of register.com's fulfillment of the obligations of
          this Section 2.8 is the presentation of the Concentric Offers
          described in Sections 2.2.3 and 2.3.3. In each subsequent monthly
          period of the Initial Term, the number of Concentric Opportunities
          will increase by 10%, such that the number of Concentric
          Opportunities meets or exceeds the monthly minimums established in
          Exhibit C.


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   2.9.   Reporting. During the Term, register.com shall provide to Concentric
          monthly reports on the number of impressions of all Concentric Offers.
          During the Term, register.com shall provide to Concentric weekly
          reports on the relative click through rates for each unique Concentric
          banner advertisement. During the Term, Concentric shall provide to
          register.com monthly reports for all hosting subscriptions that
          Concentric can attribute to the creation of a Concentric Opportunity.
          so that register.com will have the necessary information to see which
          subscribers have paid and which have discontinued the Concentric
          hosting service. In addition, Concentric shall use commercially
          reasonable efforts to provide to register.com information on the
          number hosting subscriptions generated by Concentric's marketing
          presence on the Web Properties.

   2.10.  Without limiting the foregoing, register.com reserves the right at any
          time and from time to time to amend, supplement or otherwise modify
          the design, "look and feel," layout, content, architecture and
          navigational flow of the Web Properties.

3. DISTRIBUTION OF REGISTER.COM SERVICES

   3.1.   Concentric-Branded Hosting Services. Following the Launch Date,
          Concentric shall use register.com as the exclusive third-party gTLD
          Name Domain Registration service for its Concentric-branded
          Web-Hosting and E-Commerce services. The register.com logo will be
          prominently displayed on the domain registration page of Concentric's
          Web-Hosting and E-commerce products and on all pages relating directly
          to gTLD Name Domain Registration. A "domain registration" button will
          be present on the "www.cnchost.com" web page, or its equivalent. The
          button shall hyperlink directly to Concentric's domain registration
          page, which co-branded page shall be designed by Concentric with
          consultation from register.com. Concentric shall consider in good
          faith recommendations by register.com to modify such co-branded page.
          Concentric's obligations under this Section 3.1 shall be relieved if
          Concentric chooses to use register.com's Private Label Domain
          Registration services as described in Section 3.3 below.

   3.2.   Private Label Hosting Services. To the extent Concentric is able to
          use a third party Domain Registration service for its Private Label
          Web Hosting and E-commerce services, Concentric shall use register.com
          as the exclusive third-party gTLD Name Domain Registration service for
          Private Label services sold under contracts entered into by Concentric
          after the Launch Date of this Agreement. Concentric shall use
          commercially reasonable efforts to secure register.com as the
          exclusive gTLD Name Domain Registration service used by Concentric's
          existing Private Label customers. If Concentric cannot secure
          exclusive arrangements for future or existing Private Label customers,
          it shall use commercially reasonable efforts to secure a non-exclusive
          arrangement for register.com.

   3.3.   Private Label Registration Services. If following the Effective Date,
          Concentric elects to use a Private Label Domain Registration service,
          Concentric will use register.com's Private Label gTLD Name Domain
          Registration services. Register.com shall receive co-branding on the
          primary Domain Registration web page used by Concentric for such
          Private Label gTLD Name Domain Registration services. Register.com
          shall provide Private Label Domain Registration services that are at
          competitive prices, terms and conditions. If such competitive prices,
          terms and conditions are not made available by register.com to
          Concentric in any instance, Concentric shall provide register.com with
          a right of "last refusal".

   3.4.   Performance Metrics. If during the Term any customer purchasing
          Concentric's Web Hosting service is unable to complete the Domain
          Registration process for gTLD Names within seventy-two (72) hours of
          the customer's first attempt to do so, Concentric may provide written
          notification to register.com that describes the performance problem.
          Register.com shall have thirty (30) days following such notification
          to remedy the Domain Registration process. The Domain Registration
          process shall be considered remedied when any customer purchasing
          Concentric's Web Hosting service is able to complete the Domain
          Registration process within a period of time that is within 20% of the
          "Industry Standard Registration Time" as calculated using the methods
          described in Exhibit H. If register.com does not remedy the Domain
          Registration process within thirty (30) days of Concentric's initial
          notification, then Concentric's obligations under this Section 3 to
          use register.com as the exclusive third party gTLD Name Domain
          Registration service shall be terminated. If during the Initial Term
          or during the Renewal Term Concentric provides, under the rights
          created by this Section 3.4, three (3) written notifications to
          register.com, then Concentric's obligations under this Section 3 to
          use register.com as the exclusive third party gTLD Name Domain
          Registration service shall be terminated.


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4. COMPENSATION AND FEES

   4.1.   Minimum Payment. Concentric will pay to register.com a fee of $100,000
          per month for the Initial Term (as defined in Section 6.1.3 below).
          This fee will be paid by Concentric to register.com within fifteen
          (15) days of the beginning of each monthly period during the Initial
          Term. If such payment is not made timely, Concentric will pay a late
          fee equal to 1.5% for each month or portion thereof until all past-due
          obligations are paid.

   4.2.   Incentive Payment. Concentric will pay to register.com $75 for each
          Concentric Opportunity that becomes a "Qualified Concentric Customer".
          For the purposes of this Section 4.2, a Qualified Concentric Customer
          shall mean a Web Hosting or E-Commerce customer that meets all of the
          following conditions: (a) is identified as a Concentric Opportunity
          responding to a Concentric Offer; (b) purchases a fee-bearing account
          of the type that incurs a monthly charge; (c) successfully completes
          two (2) billing cycles with Concentric, and; (d) is not among the
          first 5% of all Concentric Opportunities that purchase Web Hosting
          or E-Commerce services from Concentric in a given month. Concentric
          will make this incentive payment to register.com on the fifteenth day
          of each month following the conversion of the customer to a Qualified
          Concentric Customer. If such payment is not made timely, Concentric
          will pay a late fee equal to 1.5% for each month or portion thereof
          until all past-due obligations are paid.

   4.3.   Registration Commissions. Register.com will pay to Concentric a
          one-time commission for all Net New Registrants originated by
          Concentric, fulfilled by register.com, and that register gTLD Names.
          The commission paid by register.com to Concentric shall be 15% of the
          Net Registration Revenue or shall adhere to the commission schedule in
          Exhibit G, whichever amount is greater for a given volume of
          registered domains. Register.com shall make this commission payment on
          the fifteenth day of each month following the month during which the
          Domain Registration process is completed by the Net New Registrant. If
          such payment is not made timely, register.com will pay a late fee
          equal to 1.5% for each month or portion thereof until all past-due
          obligations are paid. For the duration of the Term, the commission
          schedule presented in Exhibit G may be substituted, at Concentric's
          sole discretion, for the commission schedule typically offered by
          register.com to other companies.

   4.4.   Audit. (a) Upon fifteen (15) business days prior notice to one Party,
          the other Party may have access to the other Party's relevant
          databases and records to conduct an audit for the sole purpose of
          verifying the commissions and incentive payments due hereunder, as the
          case may be. Each Party shall grant the other such access for a
          maximum of two (2) requests during each of the Initial Term and, if
          applicable, the Renewal Term (as defined in Section 6.1.4 below).
          Audits shall be conducted during regular business hours and shall not
          unreasonably interfere with normal business. Such audit shall be
          solely at the auditing Party's expense. However, if the audited Party
          has either overcharged or underpaid the auditing Party by more than
          five percent (5%) for the time period subject to audit, then the
          audited Party shall pay the reasonable expenses of such audit. The
          findings of any audit conducted under this Section 4.4 shall be
          subject to the confidentiality requirements of Section 8.

5. OTHER SERVICE AGREEMENTS

   5.1.   Domain Parking. During the Term, Register.com will provide a domain
          parking service for all Net New Registrants whereby any domain not
          explicitly moved elsewhere will be associated with the DNS of
          register.com. During the Term, Register.com will not offer domain
          parking to any other company.


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   5.2.   SiteAmerica Divestiture If during the Term, register.com decides to
          divest the Web Hosting customer accounts served by the SiteAmerica
          shared hosting platform, which platform currently owned and operated
          by register.com, it shall provide to Concentric written notice of such
          decision. Concentric shall have the right to be the first party to
          negoitate with register.com for the proposed purchase of the
          SiteAmerica customer accounts. If the Parties do not reach agreement
          on the price, terms and conditions of such purchase within twenty (20)
          business days of register.com's written notice to Concentric, then
          register.com shall have the right to divest the Site America customer
          accounts third party. However, if the price to be paid for the
          accounts by third party is equivalent to or less than the Concentric's
          last written offer to purchase the accounts, Concentric shall have the
          right and the obligation to purchase the accounts at the price
          described in the last written offer to register.com. Any such customer
          account purchase agreement will be subject to a definitive written
          agreement containing reasonably customary terms and conditions for
          agreements of that type and that is executed and delivered by both
          Parties.

   5.3.   Server Co-Location. If at any time during the Term, register.com
          decides to open another server hosting facility in the United States
          or another country served by Concentric, register.com will use
          Concentric's server co-location facilities. Concentric shall provide
          such server co-location services that are at competitive prices, terms
          and conditions. If such competitive prices, terms and conditions are
          not made available by Concentric to register.com, register.com's
          obligations under this Section 5.4 to use Concentric's co-location
          services are relieved.

   5.4.   Reselling of Private Label Web Hosting Services. Register.com shall
          have the right to resell under a Private Label Concentric's Web
          Hosting and E-commerce services integrated with register.com's Domain
          Registration service. Register.com will be subject to all prices,
          terms and conditions of Concentric's master-reseller agreement for Web
          Hosting and E-commerce services, attached hereto in Exhibit D.

6. TERM AND TERMINATION

   6.1.   Term Definitions. The following definitions shall be used in this
          Section 6 and throughout the Agreement to govern the term of this
          Agreement and any termination thereof.

          6.1.1. "Effective Date" shall mean the date that the Investment is
                 consummated.

          6.1.2. "Launch Date" shall mean the first day of the month following
                 the month during which Concentric and register.com complete the
                 integration of the register.com Web Properties and Domain
                 Registration process with Concentric Web Hosting and E-Commerce
                 services such that all obligations of Section 2 of this
                 Agreement can be fulfilled, or such other date as mutually
                 agreed to by the Parties.

          6.1.3. "Initial Term" shall mean the period commencing on the Launch
                 Date and continuing for a period of twelve (12) months.

          6.1.4. "Renewal Term" shall mean the period commencing on the
                 termination of the Initial Term and continuing for a period of
                 twelve months.

          6.1.5. "Term" shall mean the period encompassing both periods of the
                 Initial Term and the Renewal Term.



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   6.2.   Term. This Agreement shall be effective on the Effective Date and
          shall continue until the expiration of the Initial Term, unless sooner
          terminated in accordance with Section 6.3 or extended in accordance
          with Section 6.5. If the Investment is not consummated on or before
          June 30, 1999, this Agreement shall be null and void as though never
          executed and delivered by the Parties.

   6.3.   Termination for Cause. In addition to any other rights and/or remedies
          that either Party may have under the circumstances, all of which are
          expressly reserved, either Party may terminate this Agreement if:

          6.3.1. The other Party is in material breach of any warranty,
                 representation, term, condition or covenant of this Agreement
                 and, if such breach is curable, fails to cure that breach
                 within thirty (30) days after written notice thereof (except
                 that all payment defaults shall be cured within five (5) days
                 without the need for written notice), or;

          6.3.2. The other Party makes any assignment for the benefit of
                 creditors or similar transfer; or suffers or permits the
                 commencement of any form of insolvency or bankruptcy
                 proceeding; or has any petition under any bankruptcy law filed
                 against it, which petition is not dismissed within (60) days of
                 such filing; or has a trustee or receiver appointed for its
                 business assets or any part thereof.


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          6.3.3. Register.com fails to achieve the minimum commitments for
                 Concentric Opportunities established in Section 2.8 and Exhibit
                 C for two (2) consecutive monthly periods.

   6.4.   Effect of Termination. The termination or expiration of this Agreement
          shall have no effect upon any other then-current written agreements
          between the Parties unless such other agreements expressly provide
          otherwise. Following the expiration or termination of this Agreement,
          Sections 1,2.5 (except for Section 2.5.5), 4.4, 8, 9, 10, 11, and 12
          shall survive, except that the provisions of Section 2.5 shall not
          survive beyond one year after the termination of this Agreement. In
          addition, the financial obligations created under Sections 4.1, 4.2,
          and 4.3 and accrued through the date of termination shall survive
          until all amounts due either Party at the time of termination of the
          Agreement are paid in full.

   6.5.   Extension. No earlier than 60 days and no later than 30 days prior to
          the end of the Initial Term, Concentric shall have the right to renew
          the agreement for the Renewal Term at revised prices, terms and
          conditions, taken as a whole which shall be no less favorable, in all
          material respects, than prices, terms and conditions agreed to with
          any Web Hosting or E-Commerce service provider.

7. MOST FAVORED NATION PROVISION

   If during the Term, register.com enters into an agreement that provides any
   pricing, terms or conditions to another one of the three third-party Web
   Hosting or E-Commerce providers allowable under this agreement that, when
   taken as a whole, are materially more favorable than those offered to
   Concentric in this Agreement, then register.com shall amend this Agreement in
   writing within five (5) days to provide Concentric with prices, terms and
   conditions that, when taken as a whole, are equivalent or more favorable than
   those offered to the other provider.

8. CONFIDENTIALITY AND PUBLICITY

   8.1.   Confidentiality. The Parties acknowledge and agree that the terms and
          conditions of the Non-Disclosure Agreement dated March 22, 1999 (the
          "NDA"), entered into by and between the Parties are incorporated into
          this Agreement and that all the terms of this Agreement and all
          discussions and negotiations related thereto and all information
          exchanged pursuant hereto are considered Confidential Information as
          defined in the NDA. In the event that any of the incorporated terms of
          the NDA are inconsistent with or conflict with this Agreement, then
          the terms of this Agreement shall prevail. The customer information
          provided to Concentric under Section 2.4 will not be subject to the
          terms of the NDA, but instead will be governed by Section 2.4.

   8.2.   Press Releases. Concentric and register.com will issue a joint press
          release announcing their commercial and financial relationship at
          least fourteen (14) days prior to any similar press release by
          register.com in conjunction with another Web Hosting or E-Commerce
          provider. At no time will either Party issue any press release or make
          any public announcement(s) relating in anyway whatsoever to this
          Agreement or the relationship established by this Agreement without
          the express prior written consent of the other Party, except as
          required by law.

9. REPRESENTATIONS AND WARRANTIES

   9.1.   General. Each Party represents and warrants that: (a) it has the right
          and authority to enter into this and to fully perform its obligations
          hereunder; (b) the services and goods it provides do not infringe upon
          the intellectual property rights of any third party; and (c) by
          entering into this Agreement, it will not violate, conflict with or
          result in a material default under any other contract, agreement,
          indenture, decree, judgment, undertaking, conveyance, lien or
          encumbrance to which it is a party or by which it or any of its
          property is or may become subject or bound.

   9.2.   Legal Authorization. Each Party represents and warrants to the other
          Party that it will, at its own expense, make, obtain, and maintain in
          force at all times during the term, all applicable filings,
          registrations, reports, licenses, permits and authorizations in order
          for it to operate to perform its obligations under this Agreement.


                                       10
<PAGE>


   9.3.   Legal Compliance. Both Parties represent and warrant that they will,
          at their own expense comply with all laws, regulations and other legal
          requirements that apply to them and this Agreement, including
          copyright, privacy and communications decency laws. Both Parties
          represent and warrant that no consent, approval or authorization of or
          designation, declaration or filing with any governmental authority is
          required in connection with the valid execution, delivery and
          performance of this Agreement.

   9.4.   Y2K Compliance. Register.com hereby represents and warrants to
          Concentric that the hardware and software that comprise register.com
          Domain Registration services and all related products provided
          pursuant to this Agreement are, and will at all times remain "Year
          2000 Compliant" defined herein as the ability to: (a) correctly handle
          date information needed for the December 31, 1999 to January 1, 2000
          date change; (b) function properly without changes in operation
          resulting from the advent of the new century assuming correct
          configuration; (c) where appropriate, respond to two digit date input
          in a way that resolves the ambiguity as to century in a disclosed,
          defined and predetermined manner; (d) if the date elements in
          interfaces and data storage specify the century, store and provide
          output of date information in ways that are unambiguous as to century;
          and (e) recognize year 2000 as a leap year.

   9.5.   EXCEPT FOR THE WARRANTIES SET FORTH IN THIS SECTION 9 NEITHER PARTY
          MAKES ANY WARRANTIES OR REPRESENTATIONS, EXPRESS OR IMPLIED,
          INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF
          MERCHANTABILITY, TITLE, AND FITNESS FOR A PARTICULAR PURPOSE.
          CONCENTRIC EXPRESSLY DISCLAIMS ANY WARRANTY THAT ACCESS TO OR USE OF
          THE CONCENTRIC WEB HOSTING OR E-COMMERCE SERVICES WILL BE
          UNINTERRUPTED OR ERROR-FREE. REGISTER.COM EXPRESSLY DISCLAIMS ANY
          WARRANTY THAT ACCESS TO OR USE OF REGISTER.COM'S DOMAIN REGISTRATION
          SERVICES WILL BE UNINTERRUPTED OR ERROR-FREE.

10. INDEMNIFICATION

    A party ("Indemnifying Party") shall, at its expense and the request of the
    other party ("Indemnified Party"), defend any third-party claim or action
    brought against the Indemnified Party, to the extent it is based upon a
    breach of any representation or warranty of the Indemnifying Party in
    Section 9 (collectively, "Indemnified Claims"). The Indemnified Party shall
    promptly notify the Indemnifying Party in writing, specifying the nature of
    the action and the total monetary amount sought or other such relief as is
    sought therein. The Indemnified Party shall cooperate with the Indemnifying
    Party at the Indemnifying Party's expense in all reasonable respects in
    connection with the defense of any such action. The Indemnifying Party may
    upon written notice to the Indemnified Party undertake to control and
    conduct all proceedings or negotiations in connection therewith, assume and
    control the defense thereof, and if it so undertakes, it shall also
    undertake all other required steps or proceedings to settle or defend any
    such action, including the employment of counsel which shall be reasonably
    satisfactory to the Indemnified Party, and payment of all reasonably
    incurred expenses. The Indemnified Party shall have the right to employ
    separate counsel to provide input into the defense, at Indemnified Party's
    own cost. The Indemnifying Party shall reimburse the Indemnified Party upon
    demand for any payments made or loss suffered by it at any time after the
    date of tender, based upon the judgment of any court of competent
    jurisdiction or pursuant to a bona fide compromise or settlement of claims,
    demands, or actions, in respect to any damages to which the foregoing
    relates. The Indemnifying Party shall not settle any claim or action under
    this Section 10 on the Indemnified Party's behalf without first obtaining
    the Indemnified Party's written permission, which permission shall not be
    unreasonably withheld or delayed, and the Indemnifying Party shall indemnify
    and hold the Indemnified Party harmless from and against any costs, damages
    and fees reasonably incurred by Indemnified Party, including but not limited
    to fees of attorneys and other professionals, that are attributable to such
    Indemnified Claims. The Indemnified Party shall provide the Indemnifying
    Party reasonably prompt notice in writing of any such Indemnified Claims and
    provide the Indemnifying Party with reasonable information and assistance,
    at the Indemnifying Party's expense, to help the Indemnifying Party to
    defend such Indemnified Claims.


                                       11
<PAGE>


11. LIMITATION OF LIABILITIES

    NEITHER PARTY SHALL BE LIABLE TO THE OTHER FOR (A) ANY AMOUNT IN EXCESS OF
    THE AMOUNTS PAYABLE UNDER SECTION 4; OR (B) ANY INDIRECT, INCIDENTAL,
    CONSEQUENTIAL, PUNITIVE OR SPECIAL DAMAGES, ARISING OUT OF OR RELATED TO
    THIS AGREEMENT INCLUDING, WITHOUT LIMITATION, DAMAGES FOR LOSS OF BUSINESS
    PROFITS, BUSINESS INTERRUPTION, LOSS OF BUSINESS INFORMATION, AND THE LIKE,
    EVEN IF SUCH PARTY HAS BEEN ADVISED OF THE POSSIBILITY OF SUCH DAMAGES. THIS
    SECTION SHALL NOT APPLY TO EITHER PARTY'S (X) CONFIDENTIALITY OBLIGATIONS
    UNDER SECTION 8; (Y) BREACH OF ITS REPRESENTATIONS, WARRANTIES AND COVENANTS
    UNDER SECTION 12.3; AND (Z) INDEMNIFICATION OBLIGATIONS UNDER SECTION 10.

12. GENERAL PROVISIONS

    12.1. Assignment. Neither Party may assign this Agreement or any rights
          and/or obligations hereunder without the other Party's prior written
          approval, which shall not be unreasonably withheld or delayed;
          however, either party may, without the other Party's approval, assign
          all its rights and obligations to an entity that either is an
          affiliate or an unaffiliated party that agrees in writing to be bound
          in connection with a merger, acquisition, or sale of all or
          substantially all of such Party's assets. Any attempted assignment,
          sub-license, transfer, encumbrance, or other disposal without such
          consent shall be void and shall constitute a material default and
          breach of this Agreement

    12.2. Proprietary Rights. The Parties agree that Concentric and/or its
          suppliers shall retain all right, title, and interest in Concentric's
          Web Hosting and E-Commerce services and any and all content,
          technology, and materials delivered by Concentric to register.com
          pursuant to this Agreement. The Parties further agree that
          register.com and/or its suppliers shall retain all right, title and
          interest in register.com's Domain Registration services and any and
          all content, technology, and materials delivered by register.com to
          Concentric pursuant to this Agreement. Neither party shall have any
          rights to any materials, content or technology provided by the other
          party hereunder except as specifically provided in this Agreement and
          shall not alter, modify, copy, edit, format, translate, create
          derivative works of or otherwise use any materials, content or
          technology provided by the other party except as explicitly provided
          herein or approved in advance in writing by the other Party.

    12.3. Each Party shall remain the owner of all right, title and interest in
          and to its trademarks, service marks, logos and tradenames, content
          and web sites, and no right, title in or to such is conveyed to the
          other Party by this Agreement. Each Party will comply with all
          reasonable guidelines and directions of the other Party with respect
          to the use of the other Party's trademarks, service marks, logos and
          tradenames. All goodwill arising out of a Party's use of the other
          Party's trademarks, service marks, logos and tradenames will inure
          solely to the benefit of the other Party. Each Party reserves the
          right to update, alter, modify and delete the content of its
          respective web sites and it respective trademarks, service marks,
          logos and tradenames at will, from time to time, and without notice to
          or permission of the other Party.

          12.3.1. Register.com may use the Concentric logo solely for the
                  purposes of fulfilling the obligations of Section 2 of this
                  Agreement. Register.com shall fully correct and remedy any
                  deficiencies in its use of the Concentric logo, upon
                  reasonable notice from Concentric. Concentric shall have the
                  sole right to and at its sole discretion may commence,
                  prosecute or defend, and control any action concerning the
                  Concentric logo.

          12.3.2. Concentric may use the register.com logo solely for the
                  purposes of fulfilling the obligations of Section 3 of this
                  Agreement. Concentric shall fully correct and remedy any
                  deficiencies in its use of the register.com logo, upon
                  reasonable notice from register.com. Register.com shall have
                  the sole right to and at its sole discretion may commence,
                  prosecute or defend, and control any action concerning the
                  register.com logo.


                                       12
<PAGE>


    12.4. Independent Contractors. The Parties are independent contractors with
          respect to each other, and nothing in this Agreement shall be
          construed as creating an employer-employee relationship, a
          partnership, agency relationship or a joint venture between the
          Parties

    12.5. Third Party Beneficiaries. Except as specifically provided herein,
          this Agreement does not provide and shall not be construed to provide
          third parties, including any customer, with any remedy, claim, and
          cause of action or privilege. The Parties specifically acknowledge and
          agree that Concentric's operating subsidiaries are intended third
          party beneficiaries of the rights under this Agreement; provided
          however, that such third party beneficiaries shall agree in writing to
          be bound by the terms of this Agreement.

    12.6. Expenses. Each Party shall pay all costs and expenses that it incurs
          with respect to the negotiation, execution, delivery and performance
          of this Agreement.

    12.7. Governing Law. This Agreement is to be construed in accordance with
          and governed by the internal laws of the State of New York without
          giving effect to choice of law. Any dispute or claim arising out of or
          in connection with this Agreement or the performance, breach or
          termination thereof, shall be finally settled by binding arbitration
          in New York City, New York under the Rules of Arbitration of the
          American Arbitration Association by an arbitrator appointed in
          accordance with those rules. Judgment on the award rendered by the
          arbitrators may be entered in any court having jurisdiction thereof.
          Notwithstanding the foregoing, either party may apply to any court of
          competent jurisdiction for injunctive relief without breach of this
          arbitration provision. If any legal action or other legal proceeding
          (including arbitration) relating to the transactions under this
          Agreement or the enforcement of any provision of this Agreement is
          brought against any Party hereto, the prevailing Party shall be
          entitled to recover reasonable attorneys' fees, costs and
          disbursements

    12.8. Force Majeure. Neither Party shall be responsible for any failure to
          perform any obligation or provide service hereunder because of any (i)
          act of God, (ii) war, riot or civil commotion, (iii) governmental acts
          or directives, (iv) strikes, work stoppage, or equipment or facilities
          shortages not in the reasonable control of either Party, or (v) other
          similar force beyond such Party's reasonable control.

    12.9. Severability. If any provision of this Agreement shall be held to be
          illegal, invalid or unenforceable, each party agrees that such
          provision shall be enforced to the maximum extent permissible so as to
          effect the intent of the parties, and the validity, legality and
          enforceability of the remaining provisions of this Agreement shall not
          in any way be affected or impaired thereby. If necessary to effect the
          intent of the parties, the parties shall negotiate in good faith to
          amend this Agreement to replace the unenforceable language with
          enforceable language that reflects such intent as closely as possible.

    12.10. Notices. All notices and requests in connection with this Agreement
           shall be given in writing and shall be deemed given as of the day
           they are received if received by noon on a business day in the city
           of receipt (otherwise on the next business day) either by messenger,
           delivery service, or in the United States of America mail, postage
           prepaid, certified or registered, return receipt requested, and
           addressed as follows:

           TO CONCENTRIC                          TO REGISTER.COM
           Concentric Network Corporation         Register.com, Inc.
           1400 Parkmoor Avenue                   575 Eighth Avenue, 11th Floor
           San Jose, CA  95126                    New York City, NY  10018
           Phone:  408.817.2800                   Phone:  212.798.9100
           Fax:  408.817.2810                     Fax:  212.594.9448
           Attention:  James Isaacs               Attention:  Alan Breitman

           or to such other address a Party may designate pursuant to this
           notice provision.

    12.11. Entire Agreement. This Agreement, which includes the Exhibits and
           other agreements expressly referenced herein, including the NDA,
           constitutes the entire agreement between the parties concerning the
           subject matter hereof and with the exception of the NDA, supersedes
           any prior agreements, representations, statements, negotiations,
           understandings, proposals or undertakings, oral or written, with
           respect to the subject matter expressly set forth herein. The
           headings contained in this Agreement are for convenience of reference
           only, shall not be deemed to be a part of this Agreement and shall
           not be referred to in connection with the construction or
           interpretation of this Agreement. Any amendment or supplement to this
           Agreement shall be in writing and duly executed by both parties.



                                       13
<PAGE>



IN WITNESS WHEREOF, the parties have entered into this Agreement as of the date
written above in the first sentence of this Agreement.



<TABLE>
<CAPTION>
         CONCENTRIC NETWORK CORPORATION                               FORMAN INTERACTIVE CORP.


<S>                                                         <C>
/s/ John Peters                                           /s/ Richard D. Forman
--------------------------------------------------        -------------------------------------------------
By (Sign)                                                 By (Sign)

John Peters                                               Richard D. Forman
--------------------------------------------------        -------------------------------------------------
Name (Print)                                              Name (Print)

E.V.P.                                                    President and C.E.O.
--------------------------------------------------        -------------------------------------------------
Title                                                     Title

06/25/1999                                                06/25/1999
--------------------------------------------------        -------------------------------------------------
Date                                                      Date
</TABLE>


<PAGE>


                                    EXHIBIT A

                [GRAPHIC: Screen shot of register.com homepage.]



<PAGE>



                                    EXHIBIT B

[GRAPHIC: Screen shot of register.com web page for websites under construction,
including statement: "Coming Soon! You have reached my future website. We
recently registered our domain name at. . . register.com the first step on the
web."]


<PAGE>

                                    EXHIBIT C

Guaranteed Monthly Minimums for the Duration of this Agreement:

                             Minimum
                            Concentric
        Month             Opportunities
        -----             -------------
          1                   16,667
          2                   18,333
          3                   20,167
          4                   22,183
          5                   24,402
          6                   26,842
          7                   29,526
          8                   32,479
          9                   35,726
          10                  39,299
          11                  43,229
          12                  47,552


<PAGE>
                                    EXHIBIT D


  [Standard Concentric Reseller Agreement Attached Hereto, for reference only]


<PAGE>




                                    EXHIBIT E

 Sample Proposed Concentric Offer for last page of Domain Registration Process:

        [GRAPHIC: Screen shot of register.com Business Resources page.]



<PAGE>


                                    EXHIBIT F



             [Standard register.com Advertising Terms and Conditions
                      Attached Hereto, for reference only]



<PAGE>


                                    EXHIBIT G

Commission Schedule for Origination of Net New Registrants

            regs./mo.                            Comm. %
                        0-500                             10%
                        501-1000                          12.50%
                        1001-2500                         15%
                        2501+                             20%

This commission schedule is subject to change by register.com with written
notification to Concentric.



<PAGE>

                                    EXHIBIT H

Calculation of "Industry Standard Registration Time"

Industry Standard Registration Time shall be calculated, by a third-party
mutually agreeable to both Parties, as follows:

1)   The top five (5) companies registering gTLD Names are identified by the
     number of domains registered in the month during which Concentric provided
     register.com with written notification of register.com's performance
     problem as described in Section 3.4.
2)   The time required to complete the Domain Registration process is gathered
     for a typical customer of each of the top five companies identified in Step
     1 above.
3)   The Industry Standard Registration Time shall be the median of the five (5)
     registration times gathered in Step 2 above.