Add details about server orchestrated multi seller flow for PAS auctions

README.md

@@ -15,11 +15,13 @@ ad targeting products.
 
 * [Overview of trust model / Coordinators](trusted_services_overview.md)
 * [Public cloud TEE requirements](public_cloud_tees.md)
+* [Cross Cloud Coordinators](cross_cloud_coordinators.md)
 
 ## Protected Audience auctions mixed mode
+
 * [Protected audience auctions mixed mode](protected_audience_auctions_mixed_mode.md)
 
-## Bidding and Auction services
+## Bidding and Auction services (B&A)
 
 * [Bidding and Auction services](bidding_auction_services_api.md)
 * Self-serve guide
@@ -39,6 +41,10 @@ ad targeting products.
 * Protected App Signals
    * [Bidding and Auction services: Protected App Signals](bidding_auction_services_protected_app_signals.md)
    * [Protected App Signals egress format](https://github.com/privacysandbox/protected-auction-services-docs/blob/main/bidding_auction_services_protected_app_signals_egress.md)
+* B&A and K-Anonymity integration
+  * [Bidding-Auction services and K-Anonymity integration](bidding-auction-services-kanon-integration.md)
+* B&A experiment support
+   * [Bidding and Auction services experiment](bidding_auction_experiment.md)
 * Cloud support
     * AWS: [Bidding and Auction services AWS cloud support and deployment guide](bidding_auction_services_aws_guide.md)
     * GCP: [Bidding and Auction services GCP cloud support and deployment guide](bidding_auction_services_gcp_guide.md)
@@ -50,12 +56,18 @@ ad targeting products.
 * [Key/Value service user-defined functions (UDFs)](key_value_service_user_defined_functions.md)
 * [Key/Value sharding](key_value_service_sharding.md)
 * [K/V Server Instance Sizing Guide](key_value_service_instance_sizing_guide.md)
-* [Key/Value Service Cost](key_value_service_cost.md)
+* [Key/Value service Cost](key_value_service_cost.md)
+* [Key/Value service hybrid mode](key_value_service_hybrid_mode.md)
+* [Passing buyer signals from B&A to TEE KV for PA flow](key_value_service_contextual_signals_propagation.md)
 
 ## Ad Retrieval service
 
 * [Protected App Signals: Ad Retrieval service](https://github.com/privacysandbox/protected-auction-key-value-service/blob/main/docs/protected_app_signals/ad_retrieval_overview.md)
 
+## B&A and TEE KV / Retrieval version compatibility
+
+* [B&A and TEE KV / Retrieval version compatibility](release_compatibility_bidding_auction_key_value_services.md)
+
 ## User Defined Function Execution
 * [Roma Bring-Your-Own-Binary](roma_bring_your_own_binary.md)
 
@@ -73,6 +85,11 @@ ad targeting products.
 
 * [Bidding and Auction services: Cost](bidding_auction_cost.md)
 * [Protected App Signals cost](protected_app_signals_cost.md)
+* [Bidding and Auction Cost Estimation Tool](bidding_auction_cost_estimation_tool.md)
+
+## Protected Auction services launch phases
+
+* [Protected Auction services launch and testing phases](protected_auction_services_launch_testing_phases.md)
 
 ## Client and server integration
 

bidding-auction-services-payload-optimization.md

@@ -116,12 +116,12 @@ compressed [`ProtectedAuctionInput`][5] request payload.
 
 #### Step 1
 
-**The buyer creates `interest groups` based on `first party advertiser cookie`**
+**The buyer creates `interest groups`**
 
-Buyers running B&A services must ensure that `trustedBiddingSignalKeys` in
-each `interest group` only include a `first party (1p) advertiser cookie`. This 
-would facilitate fetching data required by generateBid() for the interest group in
-`trustedBiddingSignals` from buyer's key / value service. 
+It is recommended to buyers running B&A services to use a first party identifier (for example `first party user ID for
+advertiser site or app`) for `trustedBiddingSignalKeys` and / or `interest group name`.
+This would facilitate fetching data required by generateBid() for the
+interest group in `trustedBiddingSignals` from buyer's key / value service. 
 
 #### Step 2
 
@@ -182,7 +182,7 @@ The only information included in each interest group are the following. Note tha
 browser will not include `adRenderId(s)` or `adComponentRenderId(s)` or `userBiddingSignals`
 or any other information in interest groups. 
   * interest group `name`
-  * `trustedBiddingSignalKeys`: Note that this must be a first party advertiser cookie
+  * `trustedBiddingSignalKeys`: It is recommended to be an identifier such as `first party user identifier per advertiser site (or app)`
   * [browserSignals][18]
 
 ##### Specification for browser signals
@@ -246,8 +246,7 @@ The browser will not include `userBiddingSignals` information in `interest group
 are sent in `ProtectedAuctionInput` request payload.
 
 The `userBiddingSignals` information per `interest group` can be made available in
-`trustedBiddingSignals`, if `first party advertiser cookie` is used as
-`trustedBiddingSignalKeys`.
+`trustedBiddingSignals`.
 
 
 #### Step 8

bidding_auction_cost.md

@@ -496,6 +496,10 @@ ghz \
 
 _Example command line call to start a two-day test run at 60 QPS_
 
+A cost estimation tool is available to help estimate B&A costs using a shorter
+duration load test (about 1 hour). See the [cost estimation tool explainer][33]
+for more details.
+
 ## Compiling costs for the test
 
 After the test is completed the results may be found in the billing explorer of
@@ -568,16 +572,6 @@ Note that this assumes a production architecture similar to that under test.
 More complex architectures to handle higher loads, such as a fan-out load
 balancing scheme, may yield different results.
 
-# Future work
-
-Enabling accurate cost estimation is an important area that the Privacy Sandbox
-team wants to support ad tech partners. To this effect, we have the current
-plan:
-
-- Publish a load generator tool that can be used by ad techs for cost analysis
-  in conjunction with methods mentioned above
-- Work with ad tech partners to measure and optimize cost
-
 [1]: http://goto.google.com/relevance-cost
 [2]: http://go/cma-notice
 [3]: https://github.com/privacysandbox/fledge-docs/blob/main/bidding_auction_services_api.md
@@ -610,3 +604,4 @@ plan:
 [30]: https://cloud.google.com/skus
 [31]: https://github.com/akshaypundle
 [32]: https://github.com/dave-garred
+[33]: https://github.com/privacysandbox/protected-auction-services-docs/blob/main/bidding_auction_cost_estimation_tool.md