ADSL Signal Measurement

Hello sir/madam

Before I begin t ask my question, I apologise for my bad English and also if here is not the right place to ask this question.

I'm an Electronics technician and my question is:

How can I measure ADSL line "attenuation" and "SNR Margin"? The only way is to request theme from the ADSLAM by a process similar to "Modem Initial training" or I can measure theme whitout connecting to ADSLAM and just by measuring signal parameters.

Your's sincerely.