OpenRTB : When the bid response send?

[aukgit]

OpenRTB: When the bid response send?

Does DSP send a bid response?
Yes (https://bit.ly/2VBQbME)

Answer By Mani.

The RTB process involves an ad exchange (or SSP) starting an auction by submitting a bid request to several DSPs. These DSPs will analyze the information in the request and submit their bid response, at which point the exchange will select the winner and return the corresponding ad info to the page or system that originally asked for an ad.

DSPs have no visibility into the auction other than submitting their own bid, meaning they couldn't see the other bids even if they wanted to. Only the exchange will see all the bids at once. Even if the DSP tried to send another bid, the exchange will just ignore the duplicate response, regardless of whether the auction still has time.

There’s also the latency aspect as many ad exchanges have a strict 100 miilisecond time limit which is barely enough for a single bid transaction. Multiple bids means another whole round trip for the bidder to get current prices and bid again, which is highly unlikely to fit in the time window, making multiple bids unfeasible from a technical perspective.

Most exchanges use a Second Price Auction to encourage bidders to submit exactly the price that they feel the impression is worth, rather than trying to game the system along with everyone else which usually only leads to lots of volatility and losses.