The following page describes the architecture of RTBKit. The following diagram shows the components that are involved in the implementation of a fully-functional bidder. The core components are supplied by RTBKit whereas the others are either off-the-shelf components or must be implemented by users of RTBKit

Core Components

This section provides a brief description of each of the RTBKit-supplied core components

Router

This is the central component of the RTB stack. It performs the following functions:

• Receives bid requests from the various exchanges
• Filters them for the bidding agents
• Augments them with extra information (by calling the augmentors)
• Mediates between multiple bids
• Ensures real-time guarantees are met
• Guarantees we do not overspend

Post-Auction Service

• Receives bids from the router that have been submitted to the exchange
• Receives notifications of wins, impressions, clicks and visits

Master Banker

This is the component that manages budgets associated with campaigns

• Authorizes spend given by bidding agents
• Keeps track of budgets for each campaign
• Tallies up the spend for each campaign

Agent Configuration Service

• Responsible for broadcasting each bidding agent's configuration to everything that needs to know about it
• The type of information that they broadcast
  • What bid requests to send
  • How to send them
  • What creatives are available
  • Who to charge for ads that are bought
  • How to identify conversion events
• Avoids the agents having to separately manage their configuration with every service they talk to
• AgentConfigurationListener class provides a way to automatically stay up to date

Service Monitor

• Checks that all processes are working correctly and provides authorization to the router for bidding on auctions at regular intervals
• Without an explicit authorization the router will drop nearly all bid requests
• Will cut off bids under the following conditions
  • No wins coming in from a given exchange
  • No impressions for a given ad server
  • Spend is exceeding reasonable levels

User-supplied Plugins

This section describes the components that users of RTBKit must supply in order to have a fully functional bidder.

Exchange Connector

An exchange connector is an exchange-specific C++ component that lives inside the router. It implements the exchange-specific logic that is needed to parse bid requests. It performs the following functions:

• Parses and normalizes bid requests
• It is responsible for sending back a bid response to the exchange within the maximum response time set by the exchange

Augmenter

• Receives a series of bid requests and will add information to them in the form of tags or data. This information can be either per account or global to all accounts.
• Subscribes to the Agent Configuration Service to know the augmentation for each client(bidding agent)

Bidding Agent

• Subscribes to a filtered stream of bid requests from the router
• Calculates the bidding price and priority for each bid
• Implements a bidding strategy

Logger

• A separate process that each component uses to save logs
• Will perform required compression and rotation
• Will also transfer logfiles to the cloud(coming soon)
• Currently the logger process is connected to both the router and the post auction service