Confustion in iTrader- one way or both way!

I have a confusion in iTrader. Suppose person A posts in BST section
for Link exchange. Person B sends a private mesage for his interest.
Now there is a deal made.

Who should ask for an itrade? Person A or Person B?
Person A initiated the thread and has got a valid "Deal thread URL".
I mean is it one way or both way? Can Person B also ask for an itrade?
If yes, what will be the deal thread URL? Please do suggest.

 

Itraders go both ways, and should be submitted by the two who are involved in the deal. Use the thread in the BST section as the deal URL.

 

Person A or B can give itrader as long as A or B created the thread. The thread URL is the thread that was created for that purpose.