Waterfall management with ironSource mediation

In this guide you will find best practices on the optimal configuration of your waterfall using ironSource mediation.

Using waterfall tiers and types

Waterfall tiers:

  1. Tier 1: Should be left blank, unless you have a guaranteed deal to deliver with highest priority.
  2. Tier 2: Should be used as your primary waterfall and set to ‘Sort by CPM’ tier type.
  3. Tier 3: Should generally be left blank, especially if using in-app bidding. You could use it as a backfill solution only, to pick up remnant impressions not filled by your primary waterfall.

Waterfall tier types:

  1. Sort by CPM 
    1. This should be your default waterfall for all instances. It’s the best solution to ensure your waterfall is well optimized with the least amount of manual work.
    2. If using LevelPlay in-app bidding, you MUST use Sort by CPM as your waterfall to achieve highest bidder performance.
  2. Manual
    1. Should be used ONLY when there’s a guaranteed deal that needs to deliver with highest priority, regardless of its eCPM. Otherwise, it should not be used.
  3. Optimized
    1. Should be rarely used, and only if multiple instances and/or bidding are not in use. 
    2. Can be used as a backfill section to your primary waterfall. If you are using as backfill, It’s recommended to have just one instance from each network in the Optimized group, without setting a fixed CPM or rate.

Setting instances rates

Top tips for setting instance rates:

  • Rates should be equal to the instances intended eCPM
  • Once the instance has eCPM has stabilized, it should be removed so the instances are ordered by actual eCPM and not the rate.

Here are three main use cases for setting instance rates. 

  1. When launching a new instance: Setting a rate will help the instance scale faster and prioritize properly in the ‘Sort by CPM’ waterfall.
  2. When launching a new app: Since all instances are brand new, setting the rate will make sure each instance is delivered in the correct order according to its intended eCPM.
  3. When adjusting the fixed CPM of an existing instance: This will make sure the instance reacts immediately to the change, and is properly sorted in the ‘Sort by CPM’ waterfall.

Creating and Managing Waterfall Groups

Groups allow the flexibility to control your waterfall based on country and user segment or a combination of both:

  • Be careful not to create groups that have conflicting settings.
  • There is a hierarchy function in the group order, meaning the 1st group will override the 2nd group, and so on.  Keep this in mind when applying the same countries or user segments to multiple groups.
  • Deactivate instances intended for specific countries with a specific deal on other countries/groups where that deal does not apply. This ensures there’s no ad delivery on countries outside of the agreed targeting and terms, which can influence or harm the performance of the deal.

Bidding best practices

    1. When using a hybrid model, meaning a waterfall both bidding and non-bidding sources, move all non-bidding sources to one tier, and utilize the Sort by CPM waterfall tier type to ensure the non-bidding instances are sorted in descending order according to eCPM. Instances out of order could result in sub-optimal distribution of impressions between the bidders and the waterfall.
    2. To maximize performance, networks should operate as only bidders or non-bidders, never both at the same time in the same waterfall.
    3. Use multiple bidding networks.  Performance is expected to be stronger when more than one network is participating in the auction.
    4. For non-bidding instances, after creating a new instance or updating the price of an existing instance, utilize the rate function to assign the intended eCPM of that instance. This ensures immediate optimization to maintain a waterfall sorted by descending eCPM.
    5. Deprecate waterfall instances that have low traffic (less than 2% SOV of revenue) which could also affect the distribution of impressions to the bidder and waterfall.
    6. Consider deprecating networks contributing less than 5% share of voice of overall revenue, to reduce operation overhead by managing fewer sources.
    7. Use the bidding test to find the right strategy – in-app bidding hybrid or a traditional waterfall without bidding.
    8. Strategize with your ironSource team.  Together with your account manager, you can decide on a monetization action plan to deliver optimal performance and revenue.