Server-Side Bid Flow 9 Server Bid Flow Server Client Prebid Server Demand Partners Ad Server 1 one request 2 OpenRTB 3 bids 4 target KVs 5 creative P_
Server-Side Bid Flow Server Bid Flow 9 Step 1 moves the HTTP origin from browser to server — the key shift vs 3 . Bidders see a data-center IP, not the user, so cookies, UA, and IP must be forwarded or rebuilt via cookie sync. That hop costs 10-30% in match rates 10 . Most teams run hybrid: identity-sensitive bidders stay client-side, latency-tolerant ones move to PBS 39 . FIELD NOTES → Set s2sConfig.timeout to 50-75% of bidderTimeout for headroom → PBS silently drops slow bidders; no error surfaces client-side → 4KB uids cap gone server-side; user.ext.eids has no limit P_ atd.postindustria.com/9

How It Works

Step [1] moves the HTTP origin from browser to server — the key shift vs {3}. Bidders see a data-center IP, not the user, so `cookies`, `UA`, and `IP` must be forwarded or rebuilt via cookie sync. That hop costs 10-30% in match rates {10}. Most teams run hybrid: identity-sensitive bidders stay client-side, latency-tolerant ones move to PBS {39}.

Field Notes

  • Set `s2sConfig.timeout` to 50-75% of `bidderTimeout` for headroom
  • PBS silently drops slow bidders; no error surfaces client-side
  • 4KB `uids` cap gone server-side; `user.ext.eids` has no limit

Questions about Server-Side Bid Flow?

Get expert guidance from our team. We'll help you implement it.