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                                                                   Exhibit 10.6B

October 27, 1999



Mr. Graham G. Pattison
145 Baytech Drive
San Jose, CA  95134

Dear Graham:

This letter shall set forth the changes to the terms and conditions of your
employment by Verilink Corporation set forth in the two letters to you from
Verilink, dated March 22, 1999, and September 21, 1999. We have agreed as
follows:

1.       The bonus referred to in the attached September 21, 1999 letter in the
         amount of $300,000.00 will be paid on or before November 1, 1999, in
         recognition of the successful transition of Verilink's operations to
         its Huntsville location.

2.       Verilink shall grant you an additional option to acquire 400,000 shares
         of its common stock on November 1, 1999. That option shall vest as to
         25% of the shares on October 1, 2000, and at the rate of 1/48th of the
         shares at the end of each month thereafter.

3.       The Housing assistance loan referred to in Paragraph 9 of the March 22,
         1999 letter shall be modified as follows:

         a)       You shall receive a housing assistance loan of $300,000, which
                  shall be interest free. If you purchase a home in Alabama with
                  the proceeds of that loan and subsequently sell that home for
                  less, after deduction of all costs of sale, than its purchase
                  price, the principal amount of the loan, will be
                  correspondingly reduced. Verilink shall reimburse you for any
                  tax liability incurred by you by reason of such reduction at
                  the maximum applicable marginal tax rate. The loan shall be
                  evidenced by a Promissory Note in the form attached hereto as
                  Exhibit A.

         b)       You shall receive an additional loan in the amount of
                  $300,000. The outstanding principal balance of the loan will
                  be repaid upon the earlier of (i) your leaving the Company for
                  any reason, provided however, that, for purposes of this
                  paragraph 3(b)(i) 25% of the loan will be forgiven for each
                  full year that you remain employed by Verilink; or (ii) within
                  one year after the value of your exercisable Verilink stock
                  options exceeds $2,000,000 (fair market value of stock subject
                  to exercisable options less total exercise price of such
                  options). Interest shall be forgiven. Verilink shall reimburse
                  you for any tax liability resulting from forgiveness of this
                  loan at the maximum applicable marginal tax rate. This loan
                  shall be evidenced by a Promissory Note in the form attached
                  hereto as Exhibit B.




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Mr. Graham G. Pattison
October 27, 1999
Page 2


4.       Verilink shall reimburse you for any tax liability incurred by you by
         reason of any payments made to you pursuant to Paragraph 7 of the March
         22, 1999 letter at the maximum applicable tax rate.

5.       In addition to the Housing loan described in Paragraph 3 above, for so
         long as you own two houses, Verilink shall reimburse you for real
         estate taxes, insurance, maintenance and similar costs associated with
         your Alabama house. To the extent not deductible by you, Verilink shall
         reimburse you for any tax liability associated with such payments at
         the maximum applicable marginal tax rate.

6.       Paragraph 6 of the March 22, 1999 letter shall be modified to provide
         that after one year of employment, any termination of your employment
         by Verilink other than for cause shall entitle you to receive the
         benefits provided in the Verilink Change of Control Severance Benefits
         Agreement as if a change in control had preceded such termination.

7.       Paragraph 8 of the March 22, 1999 letter shall be deleted.

8.       Except as set forth above, the terms of the letters of March 22, 1999
         and September 21, 1999 shall remain in full force and effect.

Very truly yours,

VERILINK CORPORATION



By:      /s/ John C. Batty
   -----------------------------------------
         John C. Batty, CFO


I accept the foregoing offer:

         /s/ Graham G. Pattison
--------------------------------------------
         Graham G. Pattison

Date:             10/28/99
        ------------------------------------



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                                    EXHIBIT A

                                 PROMISSORY NOTE

$300,000.00                                              _________________, 1999



         FOR VALUE RECEIVED, the undersigned hereby promises to pay to Verilink
Corporation ("Verilink") at Huntsville, Alabama, the principal amount of Three
Hundred Thousand Dollars ($300,000.00). All principal due under this Note shall
be paid on the earlier of (1) termination of the undersigned's employment by
Verilink for cause, as defined in the undersigned's employment letter dated
March 22, 1999; (2) ninety (90) days after the undersigned voluntarily
terminates his employment by Verilink; (3) one year after the undersigned's
employment by Verilink terminates for any reason not set forth in (1) or (2)
above; or (4) ________________. Principal is payable in lawful money of the
United States.

         This Note may be prepaid at any time, in whole or in part, without
premium or penalty.

         If action should be instituted on this Note, the undersigned agrees to
pay the holder, in addition to such amounts owed pursuant to this Note, all
costs of collection, including a reasonable sum of attorney's fees.

         This Promissory Note is secured by a certain Deed of Trust and
Assignment of Rents of even date herewith, encumbering certain real property
owned by the undersigned in Alabama. The principal balance of this Note shall be
reduced by the amount by which the net proceeds from the sale by the undersigned
of such property after deduction of all costs of sale is less than its purchase
price.

         This Promissory Note shall be governed by the laws of the State of
Alabama.


                                        -----------------------------------
                                                Graham G. Pattison



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                                    EXHIBIT B

                                 PROMISSORY NOTE

$300,000.00                                              _________________, 1999



         FOR VALUE RECEIVED, the undersigned hereby promises to pay to Verilink
Corporation ("Verilink") at Huntsville, Alabama, the principal amount of Three
Hundred Thousand Dollars ($300,000.00). All principal due under this Note shall
be paid on the earlier of (i) termination of the undersigned's employment by
Verilink for any reason provided, however that for purposes of this paragraph
(i), the principal balance of this Note will be reduced by 25% each full year
that the undersigned remains employed by Verilink; or (ii) within one (1) year
after the value of the undersigned's exercisable Verilink stock options exceed
$2,000,000 (fair market value of stock subject to exercisable options less total
exercise price of such options). Interest shall be forgiven.

         This Note may be prepaid at any time, in whole or in part, without
premium or penalty.

         If action should be instituted on this Note, the undersigned agrees to
pay the holder, in addition to such amounts owed pursuant to this Note, all
costs of collection, including a reasonable sum of attorney's fees.

         This Promissory Note shall be governed by the laws of the State of
Alabama.


                                        -----------------------------------
                                                Graham G. Pattison