Real Time Bidding is a form of programmatic buying that allows media buyers to purchase display ad inventory down to the impression level. The slide shows how this process works: What happens between bidders, DSPs and SSPs.

1. RTB PROCESS
DSP 1
Ad Network 1
Bidders
DSP 2
Ad Exchange 1
SSP
1
DSP
SSP sends ad unit site, placement and user
(cookie) info to all parties participating in auction
(DSP/Ad exch/Ad net)
2
5
SSP receives bids from all
parties and reviews each
bid for highest price and
media buyer’s general info
to secure no conflict of
interest in accepting the
bid
DSP submits bids back to
SS, inserts ad tag or
redirect to initiate adserving process should it
win the impression.
4
6
SSP passes ad tag of
winning bidder along to
the user’s browser to
initiate the ad-serving
process
7
Ad is served
Media buyer’s DSP looks at
the passed cookie to
determine whether it’s a
match for a user already in its
database
3a
If DSP recognize cookie:
reviews the user’s cookie info
against what it has in the DSP
database to decide how
important this impression is to
the media buyer.
Also reviews site/placement
info.
à uses all this info to inform
bid price
3b
If DSP does not recognize
cookie: it will most likely pass
on bidding for the impression.
Or it could decide the site/
URL information is strong
enough to still merit a bid.
It could bid but probably at a
lower value.