--- title: Satellite Messaging Basics description: Satellite Messaging Basics & the differences between SBD and IMT pipelines --- [Skip to content](https://info.everywherecomms.com/knowledge/sbd-vs-imt#main-content) [![EVERYWHERE\_logo\_Color-3](https://info.everywherecomms.com/hs-fs/hubfs/EVERYWHERE_logo_Color-3.png?width=225&height=35&name=EVERYWHERE_logo_Color-3.png)](https://info.everywherecomms.com/knowledge/?hsLang=en) - Quick Start Show submenu for Quick Start - [Transferred Device Setup Tutorial](https://support.everywherecomms.com/showcase/cme7gei8t01cpwv0its994lps?utm_source=cp-menu) - [New Device App Setup Tutorial](https://support.everywherecomms.com/showcase/cmem2r4r501io1j0hoe2lf2gk?utm_source=cp-menu) - [Bluetooth Pairing Tutorial](https://everywherecomms.com/pages/bluetooth-pairing-everywhere-app) - Resources Show submenu for Resources - [Learning Tour](https://support.everywherecomms.com/demo/cmdnhq1sy078a9f96oxjfxl89?utm_source=cpmenu) - [How-to Videos](https://www.youtube.com/playlist?list=PLEPJrMjMTsUrX5PVx6CzSoXqFiSeYqRwv) - [Status Page](https://everywherecomms1.statuspage.io/) Open main navigation Close main navigation - Quick Start Show submenu for Quick Start - [Transferred Device Setup Tutorial](https://support.everywherecomms.com/showcase/cme7gei8t01cpwv0its994lps?utm_source=cp-menu) - [New Device App Setup Tutorial](https://support.everywherecomms.com/showcase/cmem2r4r501io1j0hoe2lf2gk?utm_source=cp-menu) - [Bluetooth Pairing Tutorial](https://everywherecomms.com/pages/bluetooth-pairing-everywhere-app) - Resources Show submenu for Resources - [Learning Tour](https://support.everywherecomms.com/demo/cmdnhq1sy078a9f96oxjfxl89?utm_source=cpmenu) - [How-to Videos](https://www.youtube.com/playlist?list=PLEPJrMjMTsUrX5PVx6CzSoXqFiSeYqRwv) - [Status Page](https://everywherecomms1.statuspage.io/) - [Contact Support](https://www.everywherecomms.com/contact-support.html) [Contact Support](https://www.everywherecomms.com/contact-support.html) The EVERYWHERE Knowledge Base – support for onboarding, training, and support. - There are no suggestions because the search field is empty. 1. [EVERYWHERE Knowledge Base](https://info.everywherecomms.com/knowledge?hsLang=en) 2. [Knowledge & Resources](https://info.everywherecomms.com/knowledge/knowledge-resources?hsLang=en) 3. [FAQs](https://info.everywherecomms.com/knowledge/knowledge-resources?hsLang=en#faqs) # Satellite Messaging Basics ## Messaging on the EVERYWHERE platform is powered by one of two sources. Short Burst Data (SBD) or Iridium Messaging Transport (IMT). Both operate over the same global Iridium constellation, but they are designed for different types of data and use cases. **SBD (Short Burst Data)** Iridium's legacy model, currently supporting the full line of inreach devices today. Its a satellite pathway that powers text messages (160 Characters), check-ins, and SOS alerts. **IMT** **(Iridium Messaging Transport)** is a newer Iridium pathway built to carry text files up to 1,600 characters. If your message exceeds the limit, it will be split up and sent in multiple messages. It also allows users to send and receive 30-second voice & photo messages. ### What SBD is, in practical terms SBD sends small bursts of information, very reliably, from places with no cell service at all. It was built for exactly what your field teams do: send a short message, drop a location point, confirm a check-in, trigger an SOS. What that looks like day to day - Messages are short and text only. *Roughly 160 characters, no photos or attachments.* - Tracking points, check-ins, and SOS alerts all ride the same pathway as your messages. - The device needs a clear view of the sky. Tree cover, canyon walls, vehicle roofs, and buildings all slow things down. - Weather and cloud cover do not affect delivery. - Delivery is measured in a window, not in seconds. Usually it is quick. In poor conditions it can take up to 30 minutes. --- ### **Three things that explain almost every timing question** SBD is very reliable, but it does not behave like a phone on a cell network. If you understand these three behaviors, most "my message was slow" questions answer themselves. | **1** | Outbound messages go out on the **next available satellite**   Iridium satellites orbit low and move fast. Your device holds the message until one passes overhead with a clear line of sight, then sends it. There is no tower waiting to receive it the moment you hit send. A message sitting in "sending" is usually waiting for its ride, not failing. | | --- | --- | | **2** | Incoming messages **arrive on your tracking schedule**   The device is not listening to the satellite network all the time. It checks for new messages when it sends a tracking point. Your tracking interval is also your inbound message interval. A faster tracking rate gets messages to the field faster. There is a way to mannually ask the inReach to check for inbound messages in the inReach device settings. | | --- | --- | | **3** | When you are stationary, the device uses the stationary interval **to save battery**   If the device sits in one place for about three to five tracking cycles, it decides it is parked and switches to the stationary interval set on your account. That saves battery and message usage while a truck sits at camp or a device sits on a desk overnight.This can be adjusted in the Hub. | | --- | --- |   **Before you report a delayed message** Check the tracking rate on the device and whether it had been sitting still. A 30 minute tracking interval and a stationary device explain most slow inbound messages. If you need faster two way messaging, ask your Hub admin to shorten the tracking interval or the stationary interval on your account. ### Where IMT fits IMT carries up to 100 KB in a single message and keeps a live link to the network, so messages land when they are sent instead of on a timer. That is what makes photos and voice notes possible, and it is why two-way conversations feel closer to texting (up to 1,600 characters). IMT runs on newer hardware only. Today that means the **Messenger Plus, the Mini 3 Plus, and the H1i Plus**. **What that looks like day to day** - Messages can carry more than text. When the device is paired with the EVERYWHERE app, you can send photos and voice notes over satellite along with your messages. - Photos send a low resolution preview first so the message gets through fast. You can pull the full resolution version later over Wi-Fi, cellular, or on demand over satellite. - Voice notes are short audio clips. Each one arrives with an automatic text transcription, so the recipient can read it or listen to it. - [Getting Started](https://info.everywherecomms.com/knowledge/getting-started?hsLang=en#main-content) - [Welcome to EVERYWHERE](https://info.everywherecomms.com/knowledge/getting-started?hsLang=en#welcome-to-everywhere) - [Device Activation](https://info.everywherecomms.com/knowledge/getting-started?hsLang=en#device-activation) - [Connectivity & Pairing](https://info.everywherecomms.com/knowledge/getting-started?hsLang=en#connectivity-pairing) - [First-Time Admin Setup](https://info.everywherecomms.com/knowledge/getting-started?hsLang=en#first-time-admin-setup) - [Field Devices & App](https://info.everywherecomms.com/knowledge/field-devices-app?hsLang=en#main-content) - [Messaging](https://info.everywherecomms.com/knowledge/field-devices-app?hsLang=en#messaging) - [Notifications & Alerts](https://info.everywherecomms.com/knowledge/field-devices-app?hsLang=en#notifications-alerts) - [Tracking & Location](https://info.everywherecomms.com/knowledge/field-devices-app?hsLang=en#tracking-location) - [SOS Basics (User View)](https://info.everywherecomms.com/knowledge/field-devices-app?hsLang=en#sos-basics-user-view) - [Device Guides](https://info.everywherecomms.com/knowledge/field-devices-app?hsLang=en#device-guides) - [Check-ins](https://info.everywherecomms.com/knowledge/field-devices-app?hsLang=en#check-ins) - [Hub for Admins](https://info.everywherecomms.com/knowledge/hub-for-admins?hsLang=en#main-content) - [Device Management](https://info.everywherecomms.com/knowledge/hub-for-admins?hsLang=en#device-management) - [Alerts & Notifications](https://info.everywherecomms.com/knowledge/hub-for-admins?hsLang=en#alerts-notifications) - [Tracking & Location](https://info.everywherecomms.com/knowledge/hub-for-admins?hsLang=en#tracking-location) - [Reports & Analytics](https://info.everywherecomms.com/knowledge/hub-for-admins?hsLang=en#reports-analytics) - [Features](https://info.everywherecomms.com/knowledge/hub-for-admins?hsLang=en#features) - [User & Device Management](https://info.everywherecomms.com/knowledge/hub-for-admins?hsLang=en#user-device-management) - [SOS & Safety](https://info.everywherecomms.com/knowledge/sos-safety?hsLang=en#main-content) - [Initiating SOS](https://info.everywherecomms.com/knowledge/sos-safety?hsLang=en#initiating-sos) - [Cancelling SOS](https://info.everywherecomms.com/knowledge/sos-safety?hsLang=en#cancelling-sos) - [SOS Escalation Flow](https://info.everywherecomms.com/knowledge/sos-safety?hsLang=en#sos-escalation-flow) - [Testing SOS & Signal](https://info.everywherecomms.com/knowledge/sos-safety?hsLang=en#testing-sos-signal) - [Safety Best Practices](https://info.everywherecomms.com/knowledge/sos-safety?hsLang=en#safety-best-practices) - [Knowledge & Resources](https://info.everywherecomms.com/knowledge/knowledge-resources?hsLang=en#main-content) - [FAQs](https://info.everywherecomms.com/knowledge/knowledge-resources?hsLang=en#faqs) - [Quick Help](https://info.everywherecomms.com/knowledge/knowledge-resources?hsLang=en#quick-help) - [Integrations](https://info.everywherecomms.com/knowledge/knowledge-resources?hsLang=en#integrations) - [Billing](https://info.everywherecomms.com/knowledge/knowledge-resources?hsLang=en#billing) - [Announcements & Updates](https://info.everywherecomms.com/knowledge/knowledge-resources?hsLang=en#announcements-updates) [![EVERYWHERE\_logo\_Color\_Connected-1](https://info.everywherecomms.com/hs-fs/hubfs/EVERYWHERE_logo_Color_Connected-1.webp?width=250&height=45&name=EVERYWHERE_logo_Color_Connected-1.webp "EVERYWHERE_logo_Color_Connected-1")](https://everywherecomms.com/) Copyright © 2026, EVERYWHERE Communications