Introduction
💡 Overview
This guide explains how a Moja tracking customer can integrate with publishers and sellers of RTB phone calls that send inbound RTB bid requests into a Moja customer’s inbound-RTB-enabled campaign.
Each publisher receives one unique inbound RTB endpoint per campaign, supplied by the Moja customer.
🚀 1. Creating an Inbound RTB Endpoint
You must create a separate inbound RTB endpoint for each publisher inside the campaign.
ℹ️ Why one per publisher?
This ensures clean attribution, routing control, and flexible passthrough.
📸 Screenshot: Adding an inbound RTB endpoint
🔗 2. How Publishers Send Inbound RTB Requests
Publishers send inbound RTB bid requests using standard HTTP(S) GET requests.
URL Format
https://rtb.moja.cloud/inbound_rtb/<endpoint_id>?tag=value&tag2=value
Formatting Rules
✔️ Correct
• First parameter begins with ?
• Additional parameters begin with &
• Use tag=value formatting
❌ Incorrect
• Do not use brackets in inbound RTB requests
• Do not send malformed or unencoded parameters
Example Inbound RTB Request
rtb.moja.cloud/inbound_rtb/inbound_rtb_1762757680608_v5hjq8?CALLER_ID=9999999999&CALLER_ZIP=99999&PUBLISHER_ID=subID
🔍 3. Moja System Values
Moja automatically derives key system values:
System Value | Description |
CALLER_ID | Caller phone number |
ZIP_CODE | Derived unless supplied inbound |
CALLER_STATE | Derived unless supplied inbound |
Using System Values in Outbound RTB
Outbound RTB uses bracket syntax:
[CALLER_ID] [ZIP_CODE] [CALLER_STATE]
⚠️ Important
Brackets are used only for outbound RTB, never inbound.
📸 Screenshot: Outbound RTB system variables
🧩 4. Sending Additional Metadata
Moja captures all inbound RTB parameters, no matter the naming.
💡 Recommendation
Publishers should send any metadata they need passed to buyers for outbound RTB requests or used for supported buyer/target filtering.
Examples include:
Traffic source
Campaign identifiers
Channel / media tags
Custom tags
Lead/session IDs
Any buyer-required metadata
Filtering Support
🚫 Current Limitation
Moja currently supports target/RTB filtering ONLY on:
• ZIP
• State
• Caller ID
Custom-value filtering is not supported yet.
📸 Screenshot: Outbound RTB parameter configuration
⭐ 5. Best Practices for Publishers
Strongly Recommended
✔️ Send these for optimal routing
• CALLER_ID
• ZIP_CODE or State
Optional but Useful
• Traffic source
• Lead/session ID
• Internal identifiers
• Buyer-required metadata
🔄 6. End-to-End Flow Summary
🧭 How the full inbound → outbound RTB process works:
Step 1 — Customer Creates Inbound RTB Endpoint
A Moja customer creates one unique inbound endpoint per publisher.
Step 2 — Publisher Sends Inbound RTB Requests
Publisher submits GET requests containing CALLER_ID, ZIP, and other metadata.
Step 3 — Moja Captures System + Custom Values
Moja derives ZIP/state when needed and stores all inbound parameters.
Step 4 — Moja Builds Possible Routes for the Call
Routing may depend on caller ID, ZIP, state, routing plans, and campaign logic.
Step 5 — Outbound RTB (Optional)
Moja prepares an outbound RTB request using:
Static fields
Dynamic system fields
Passthrough values
Step 6 — Moja Connects to the Winning Target
Moja dials out and connects the call to the winning buyer target.
Additional Information:
What does the "Duration Add (seconds)" setting mean for the inbound RTB?:
Duration Add (seconds) - it adds time to the buyers offer when you’re doing dynamic bidding. In another words, if your buyer offers a conversion at 30 seconds, you can add two seconds so that you present 32 seconds to your publisher. This helps deal with discrepancies between platforms and minimizes conversion disputes with your publisher. 
What is Phone Number Allocation Time for inbound RTB?:
Phone Number Allocation Time - this is how long the publisher has to send the call to you if they accept your bid. RTB works by allocating a dynamic telephone number that is available for the duration that you said here. If the call does not make it in that time that number goes away 
🎉 Need Assistance?
If you or your publishers need help sending inbound RTB requests, mapping fields, or configuring buyers, reach out to Moja Support — we're here to help!