FCC Part 68所引用的测试要求TIA-968-B已于2009年9月公布，与TIA-968-A和其附属条款A-1、A-2、A-3、A-4 and A-5的差异有10项，请见原文详细说明如下：

1. The structure of the document was entirely changed to reflect a redirected emphasis on interface types instead of test types;
2. Tolerances were added for Type A and Type B surge wave shapes;
3. The clause on leakage current limitations was rewritten for clarity but the requirements remain the same;
4. Coin deposit signals were added along with DTMF as examples of signals generated by terminal equipment that are used for network control;
5. Requirements that were inadvertently deleted in TIA-968-A have been restored for data circuit terminal equipment intended to operate with a programming resistor for signal level control;
6. Clarified that the tip ground state of loop start central office implemented telephones does not require transverse balance testing;
7. Clarified in the applications section that terminal equipment must comply with the applicable technical criteria of this Standard at any control adjustment employed;
8. Annex A was clarified by limiting the grandfather clauses for non-approved equipment to the United States;
9. New requirements were added for ADSL all digital mode, reach-extended ADSL and VDSL2. Other DSL requirements previously referenced from T1.417 were also added;
10. Component approval requirements previously located in TSB-129-A were included in this Standard;

其中最引人注目的是：VDSL增加了30a的Profiles。