MA5600 supports ADSL2 +, which of the following is not correct about ADSL2+ description?

(single) Is the following description correct? When negotiating the project acceptance test project with the customer, it is recommended to submit the product related product acceptance manual directly to the customer, and let the customer choose the test project.

(single) If there is multiple set-top boxes under one ONT (for example, HG850) while watching a multicast program, which of the following functions is enabled for the ONT multicast user on the OLT can ensure that one set-top box switches channels while other set-top boxes are watching. The program is not affected?

The following description which is correct? DC upgrade tool needs license support, in the absence of License, the default may be concurrent 30, under the license of the case can be up to 60 concurrent degrees.

(multiple) Types of northbound interfaces provided by the U2000 to the network management layer include?