Emergency services are complex, operating across diverse technical infrastructure and integrated networks. They require many parties to work together, from the Originating Service Provider (OSP) to the end user, and regulations vary by country, adding yet another layer of complexity.
On top of that complexity, understanding industry jargon can be a further challenge. Add in high stakes and a global scope, and it can feel outright daunting. Mastering both the jargon and the evolving dynamics within emergency services is vital for developing safe, lawful, and impactful solutions.
Location, location, location: The importance of ERL & MSAG
What is an Emergency Response Location?
Emergency Response Location is a location, typically a civic address, delivered to the Public Safety Answering Point (PSAP) to which emergency services are dispatched. You may sometimes see this shortened to just “location” or “dispatchable location.”
How does an address differ from an emergency response location?
Locations can simply be an address, but oftentimes will be more than an address, meaning address plus some additional details.
And how does Address Line 2 fit into the equation?
From a postal perspective, the Address Line 1 field is used to collect the primary address details, such as the street name and house number, and Address Line 2 is used to collect additional address information, such as apartment numbers, suite numbers, or other address designators.
From an emergency services perspective, Address Line 2 is used to communicate specific details that can help in identifying the exact location of the caller (e.g., building A, cube 145). These additional details in Address Line 2 are what, together with the civic address, comprise an “emergency response location.”
OK, locations and addresses are clear now, but MSAG is still a mystery…
What is MSAG?
Master Street Address Guide (or “MSAG”) is a database of street names and house number ranges within their associated postal communities that define Emergency Service Zones (ESZs) and their associated Emergency Service Numbers (ESNs) to enable proper routing of 911 calls.
An MSAG address is recognized by Public Safety for the dispatch of emergency responders. It is an absolute and unique address because it fits a formatting in which variants for directions, street spelling, street suffixes, and community names are not allowed.
To make it simpler, the Emergency Response Location (ERL) communicates the ‘where,’ and MSAG determines in what format the ‘where’ must be communicated depending upon the PSAP that serves the region within which the address falls.
Here’s an example:
| Entered Address | MSAG Validated Address |
| 85 Allen Street Suite 310 Rochester, NY, 14608 | 85 ALLEN ST STE 310 ROC, NY |
Now that we’ve got locations sorted, let’s talk about different categories of Emergency Services.
Connect the terms and create a strategy
Discover how to take your emergency solution from status quo to future-forward with our three-part video series.
Standard versus Nomadic Emergency Services
Here at Bandwidth, we have two primary categories of Emergency Services: Standard and Nomadic.
What are Standard Emergency Services?
Standard Emergency Services are the basic type of emergency services. They are best used to serve locations that are characterized as “static”—meaning the end user’s location will not be changing from day to day or week to week. Think handset phones in a hotel, bank or call center—these devices will stay static and won’t typically be picked up and moved by the end user.
What are Nomadic Emergency Services?
Nomadic Emergency Services are the advanced type of emergency services. They are best used to serve locations that are characterized as “non-static”— meaning the end-user can pick up their device and change locations at any time. Think softphone or embedded calling software on an application housed by a laptop or smartphone, which can easily work from any location.
Bandwidth has several product offerings under the category of Nomadic including Dynamic Location Routing (DLR), DLR for Microsoft Teams, and Emergency Calling API.
Can non-fixed devices be enabled with Standard Emergency Services and vice versa?
YES! It all depends on the behavior allowed with the device. For example, if a call center uses laptops (which could physically be picked up and relocated), but the employer mandates that the laptop devices are never taken from the office, then having an advanced nomadic solution would not be necessary. If you’re unsure of which emergency services solution is right for your organization—from Standard to mixed-use cases—talk to our solution experts!
Better together: ALI and LIS
We’ve established what locations are and how Bandwidth solutions use them; now, let’s talk a bit about how PSAPs receive location data (and other caller information).
What is Automatic Location Identification (ALI)?
Automatic Location Identification (ALI) is the automatic display at the PSAP of the caller’s phone number, call location, and supplementary emergency services location information.
This information comes from a secure database that is queried by the PSAP at the time of an emergency call. This database is not internal to Bandwidth (and is typically owned and operated by the incumbent Local Exchange Carrier (LEC), however, the ALI query does get steered/forwarded to Bandwidth’s (or the respective Originating Service Providers’) Location Information Server (LIS).
Are LIS and ALI interchangeable?
No, LIS and ALI are not interchangeable. Surprised? You’re not alone—this is one of the most common misnomers in the emergency services industry.
Location Information Server (LIS) is a database that provides Emergency Response Locations and is internal to Bandwidth (or the OSP). When an ALI query takes place, the owner of the phone number is identified, and a query out to that OSP takes place to obtain the missing bits of the caller information that is securely stored within that OSP’s LIS database.
Think of ALI and LIS as two otters locking hands just before they float down the river to the PSAP; they’re complementary database queries that together supply all the information a PSAP operator needs to assist the caller.
Emergency terms you should know for 2025
With the recently released FCC’s NG911 Implementation Order, the subject of Next Generation Emergency Services is top of mind. In discussions with customers and industry stakeholders, we’ve noticed the growing confusion surrounding ESInet and NG Core Services.
With that in mind, let’s review some of these key network elements.
What’s an Emergency Services IP Network?
Emergency Services IP Network (or “ESInet”) is a managed IP network that is used for emergency services communications, and which can be shared by all public safety agencies in a region. It provides the IP transport infrastructure upon which independent application platforms and core services can be deployed, including, but not restricted to, those necessary for providing Next Gen emergency services. ESInets may be constructed from a mix of dedicated and shared facilities and may be interconnected at local, regional, state, federal, and national levels to form an IP-based internetwork (network of networks).
Pro tip: You’ll hear ESInet pronounced as both “E-S-I”-net and “EZZEE”-net.
What are Next Generation core services?
Next Generation 911/112 Core Services (or “NG911”/“NG112”) is the set of services needed to process an emergency call on an ESInet. It includes but is not limited to, the ESRP, ECRF, LVF (LVF replaces MSAG in the U.S.), BCF, Bridge, Policy Store, Logging Services, and typical IP services such as DNS and DHCP. ESInet designates the network, whereas NG911/112 are the services that ride on the network.
More than jargon: the importance of precision in emergency preparedness
Understanding emergency terminology is crucial, but we also know that the challenges implicit in emergency services extend far beyond confusing abbreviations.
At the end of the day, providing emergency services is about protecting what matters most: your business, your resources, and your people worldwide. And that’s no small undertaking.
But don’t stress—our team of experts can help you get up to speed and find the best emergency services solution for your organization. Connect with us today for tailored advice.
