# Setting up Webex Calling emergency calling with RedSky

Systems: webex-calling

For Webex Calling administrators configuring RedSky emergency calling across US and Canadian locations.

Canonical: https://warmtransfer.net/guides/webex-calling-redsky-e911-setup

Last verified: 2026-09-24

Webex Calling enhanced emergency calling with RedSky applies to locations in the United States, its territories, and Canada[^55]. Provisioning and validation require configuration across both Webex Control Hub and the RedSky administration portal[^58].

## Before you start

- Confirm that target locations are in the United States, its territories, or Canada[^55].
- US Webex Calling users receive the RedSky service with their existing entitlement, whereas Canadian users require a separate RedSky license[^59].
- Open outbound HTTPS port 443 to `api.wxc.e911cloud.com` and `wxc.e911cloud.com` across enterprise voice and data networks[^29][^48].
- Do not rely on Cisco Calling Plan trial accounts for operational emergency service, because trial emergency calling is limited to technical evaluation[^9].

## What changes by situation

- Does the organisation already have a RedSky account? No. Create one from Control Hub.; Yes. Link the existing RedSky account..
- Which endpoints need a dispatchable location? Only fixed, on-premises desk phones and devices.; Fixed devices plus users who carry Webex App between networks..
- How do the RedSky-enabled locations reach the PSTN today? Cisco Calling Plan or cloud PSTN configured on the location.; A customer-managed Local Gateway..

## Step 1: Confirm scope, entitlement and network reachability

### Do
Verify that network firewalls permit outbound traffic to https://api.wxc.e911cloud.com and https://wxc.e911cloud.com on port 443[^29][^48]. Ensure that Canadian locations have RedSky licenses assigned and US users have their standard Webex Calling entitlement[^59].

### Verify
Suggested check: From the voice and data VLANs of each site, confirm that both e911cloud.com hosts can be reached over HTTPS.

### Rollback
Suggested rollback: Remove firewall exceptions if the project is discontinued.

## Step 2: Create or link the RedSky account in Control Hub

**No. Create one from Control Hub.**

### Do
Navigate to Services > PSTN & Routing > Settings > Enhanced Emergency Calling[^45]. Choose the option to create a new account, then enter the email address for the RedSky administrator login and the partner organisation ID[^21].

### Verify
Confirm receipt of the administrator credentials once RedSky provisioning finishes, which can take up to 2 business days[^1]. Log in to the RedSky administration portal using that email address[^21].

### Rollback
If emergency calls must be handled by the PSTN provider instead, select the option to opt the organisation out of RedSky, reverting to telephone-number-based emergency service[^44].

**Yes. Link the existing RedSky account.**

### Do
Navigate to Services > PSTN & Routing > Settings > Enhanced Emergency Calling[^45]. Select the option to log in to an existing account, then enter the partner administrator email, partner administrator password, and the RedSky Organization ID[^27].

### Verify
Verify that Control Hub accepts the credentials and shows the Enhanced Emergency Calling account as linked[^27].

### Rollback
If emergency calls must be handled by the PSTN provider instead, select the option to opt the organisation out of RedSky, reverting to telephone-number-based emergency service[^44].

## Step 3: Build buildings and locations in RedSky

### Do
In the RedSky administration portal, configure each building using a validated civic street address, then configure sub-locations within each building such as floors or wings to establish a dispatchable location[^7][^13]. Alternatively, evaluate the Control Hub toggle that automatically creates RedSky buildings and locations, which is disabled by default for Webex Calling customers[^6].

### Verify
Verify that every enabled Webex Calling location corresponds to a building and location profile in the RedSky portal, noting that emergency calls from missing locations are re-routed to emergency call relay centres[^37].

### Rollback
Delete unnecessary building and location entries directly in the RedSky portal, as deleting a location in Control Hub does not remove the corresponding building from RedSky[^24].

## Step 4: Build the network discovery wiremap

### Do
In the RedSky administration portal, associate network discovery elements—such as IP subnets, switch chassis and ports, or wireless access point BSSIDs—with the configured E911 locations[^60][^30]. Do not configure CDP, as CDP is unsupported for RedSky network discovery[^10]. Define subnet or switch associations to cover client computers connected to an IP phone pass-through port, because switch LLDP frames do not pass beyond the phone[^47].

### Verify
Confirm that all corporate subnets, BSSIDs, and switches map to locations, as RedSky relies on these wiremap definitions to detect caller location[^60].

### Rollback
Suggested rollback: Remove or update the network element records in the RedSky administration portal.

## Step 5: Configure on-site alerts in RedSky

### Do
In the RedSky administration portal, configure emergency alert notifications to security teams via email, SMS, or desktop applications[^50]. Ensure alerting complies with federal MLTS requirements to notify a central location contemporaneously with the 911 call[^15][^16]. Note that Control Hub also provides an independent emergency notification email, which is disabled by default, English-only, and delivered from a do-not-reply address[^19].

### Verify
Suggested check: Verify that emergency response recipients receive test notifications when emergency test calls are placed.

### Rollback
Suggested rollback: Remove or edit notification recipients and alerting rules in the RedSky portal.

## Step 6: Run the Control Hub E911 location wizard

### Do
In Control Hub, launch the location wizard for configuring emergency calling with RedSky[^62]. Step through and confirm each stage of completed RedSky portal work: update service settings, set up alerts, configure network elements, and enable emergency calling[^62]. Confirm during the wizard that alerts are configured in accordance with FCC regulations[^61].

### Verify
Verify that all confirmation checkpoints in the wizard complete successfully[^62].

### Rollback
Suggested rollback: Adjust any misconfigured settings in the RedSky portal and re-run the wizard.

## Step 7: Turn on location integration, but not routing yet

### Do
In Control Hub, go to Management > Locations > (location) > Calling > Enhanced Emergency Calling[^36]. Turn on the service and enable the checkbox "Allow RedSky to receive network connectivity information and test calls" to allow MPP phones to reach test number 933[^20]. Reinitialise or resync HELD devices immediately, or wait up to 24 hours for devices to automatically poll for new configurations[^31].

### Verify
Verify that saving the location configuration updates its status to Location Integration On[^36].

### Rollback
Suggested rollback: Turn off the Enhanced Emergency Calling toggle on the location in Control Hub.

## Step 8: Prepare how each kind of endpoint gets its location

**Only fixed, on-premises desk phones and devices.**

### Do
Rely on HELD network reporting to determine locations for MPP desk phones[^30]. For non-HELD devices, ensure an associated location is configured against the device caller ID in the RedSky portal, because non-HELD endpoints use asserted caller ID to establish location[^42]. For DECT handsets and ATAs that do not communicate directly with RedSky, associate a location with their caller ID in the RedSky portal[^23]. Configure an emergency callback number (ECBN) for each location and user using their own number, the location default, or another number within the location[^26][^25]. Cisco recommends establishing administrative controls so non-HELD endpoints are not moved without administrator approval[^43].

### Verify
Suggested check: Confirm in the RedSky portal that each non-HELD device, DECT handset, and ATA caller ID has an assigned location, and verify in Control Hub that an ECBN is populated on all target locations and users.

### Rollback
Suggested rollback: Remove static caller ID location mappings in RedSky and restore original ECBN settings in Control Hub.

**Fixed devices plus users who carry Webex App between networks.**

### Do
Configure fixed MPP, non-HELD, DECT, and ATA devices with appropriate wiremap entries, caller ID associations, and ECBN settings[^30][^42][^23][^26][^25]. For Webex App users, ensure device OS location permissions are enabled (Location Services on macOS 12 or later, and while-in-use permissions on iPad and Android tablets)[^3]. Instruct off-premises users to enter their dispatchable civic address when Webex App prompts upon detecting a new network[^4][^40]. Note that Webex App automatically reuses previously entered addresses on known networks[^41]. For remote workers with a fixed, non-mobile US or Canadian number, configure a custom emergency service address under Management > Users > Calling > Numbers[^22]. Instruct users on how to update addresses manually (on Windows via profile picture > Help > About > Notices and disclaimer > Update location; on mobile via profile picture > About > Notices & Disclaimers > Update location)[^5]. Remind users that Webex App on mobile devices with cellular connections places emergency calls through the native dialer rather than RedSky[^11], and that relay centre call fees are billed back to the customer if an address is missing[^51]. In the field, customers instruct users to supply complete addresses in standard US format[^28].

### Verify
Verify that Webex App prompts an off-premises test user for an address and caches it on subsequent reconnections[^40][^41]. Verify that an unrecognised address returns a suggested address for user confirmation[^2].

### Rollback
Suggested rollback: Clear custom user emergency service addresses in Control Hub and prompt users to re-enter network locations within Webex App.

## Step 9: Confirm dial behaviour meets Kari's Law

### Do
Configure outgoing permissions and dial plans so users can dial 911 directly without an outside access digit such as 9[^12].

### Verify
A 933 test call dialled with no prefix reaches the emergency test IVR, which announces the caller ID and the currently known address[^56].

### Rollback
Suggested rollback: Direct dialing configuration is retained to satisfy regulatory obligations.

## Step 10: Test with 933 from every endpoint type

### Do
Place test calls from every endpoint assigned to the location, including HELD-capable MPP phones, soft phones, and non-HELD devices[^57]. When users connect off-premises, have them verify the prompt to enter a dispatchable address[^40].

### Verify
Confirm that the IVR for a 933 test call announces the caller ID and the currently known address for that device[^56]. Verify that emergency notification alerts are delivered to configured recipients[^50]. Note that live calls with unlocatable addresses fall back to an emergency relay centre call taker[^52].

### Rollback
Suggested rollback: Testing calls make no permanent configuration changes and do not require rollback.

## Step 11: Route emergency calls to RedSky

**Cisco Calling Plan or cloud PSTN configured on the location.**

### Do
After test calls are confirmed, navigate to the location in Control Hub and enable "Route Emergency Calls to RedSky"[^54]. Emergency calls from all endpoints at the location will route to the E911 service instead of the configured PSTN[^49]. Maintain a valid emergency service address on the location, as Cisco Calling Plan mandates a default location address[^8].

### Verify
Verify that the location status displays Routing On[^54]. Place an additional 933 test call to verify that the IVR announces the device caller ID and known address[^56].

### Rollback
Suggested rollback: Toggle "Route Emergency Calls to RedSky" off in Control Hub and verify emergency dialing.

**A customer-managed Local Gateway.**

### Do
After test calls are confirmed, navigate to the location in Control Hub and enable "Route Emergency Calls to RedSky"[^54]. Emergency calls from the location—including nomadic endpoints associated with users at that location—will route directly to the E911 service instead of through the Local Gateway[^34]. Locations that remain unenabled continue to route all calls through their configured Local Gateway[^35].

### Verify
Verify that the location status displays Routing On[^54]. Place an additional 933 test call to confirm emergency connectivity and address announcement[^56].

### Rollback
Suggested rollback: Toggle "Route Emergency Calls to RedSky" off in Control Hub and verify emergency dialing.

## Step 12: Brief users and responders on emergency-call behaviour

### Do
Brief emergency response personnel and staff on device call-handling behavior:
- HELD-capable MPP desk phones prevent the caller from hanging up an active emergency call, requiring the remote dispatcher to terminate the call or the user to manually reset the phone[^38].
- Mid-call telephony features—including hold, transfer, and conference—are unavailable on MPP devices during emergency calls[^39].

### Verify
Suggested check: Confirm that internal security desk documentation and end-user guidance reflect these emergency calling constraints.

### Rollback
Suggested rollback: Update operational briefing documents as required.

## Applicability

Applies to: Cisco Webex Calling, Cisco Webex App, Webex Calling - Cisco Calling Plan, and US Federal Communications Commission 47 CFR Part 9. Deployments: multi-tenant and any. Sources checked 2026-09-24. The RedSky integration applies to Webex Calling locations within the United States, its territories, and Canada; locations elsewhere retain standard PSTN emergency calling[^55]. US users are covered by Webex Calling entitlements at no extra charge, while Canadian users require an add-on RedSky license[^59][^63]. RedSky network discovery does not support VPN interfaces, which are filtered out[^64].

## What remains uncertain

Whether emergency call routing returns to the original Local Gateway or default PSTN immediately upon disabling the "Route Emergency Calls to RedSky" toggle is not covered by the sources below.

The exact behavior of DECT and ATA endpoints regarding HELD support across specific firmware releases is not covered by the sources below.

## Sources

[^1]: Provisioning a new RedSky account can take up to two business days. Source: [Enhanced emergency calling for Webex Calling](https://help.webex.com/en-us/article/av6oo3/Enhanced-emergency-calling-for-Webex-Calling), Create a new account. Checked 2026-09-24.
[^2]: If an address a user enters in Webex App cannot be found, a suggested address is shown for the user to review and apply. Source: [Enhanced emergency calling for Webex Calling](https://help.webex.com/en-us/article/av6oo3/Enhanced-emergency-calling-for-Webex-Calling), Location detection - address validation. Checked 2026-09-24.
[^3]: On macOS 12 or later Webex App needs Location Services enabled, and on iPad and Android tablets it needs location permission while the app is in use. Source: [Webex App | Update your location for emergency services](https://help.webex.com/en-us/article/nd29pkl/Webex-App-|-Update-your-location-for-emergency-services), E911 service (device permissions note). Checked 2026-09-24.
[^4]: Under the E911 service, Webex App prompts the user for a location when E911 is first enabled and when the user connects to a new network. Source: [Webex App | Update your location for emergency services](https://help.webex.com/en-us/article/nd29pkl/Webex-App-|-Update-your-location-for-emergency-services), E911 service. Checked 2026-09-24.
[^5]: Users can update their emergency location manually: on Windows via profile picture > Help > About > Notices and disclaimer > Update location, and on mobile via profile picture > About > Notices & Disclaimers > Update location. Source: [Webex App | Update your location for emergency services](https://help.webex.com/en-us/article/nd29pkl/Webex-App-|-Update-your-location-for-emergency-services), E911 service. Checked 2026-09-24.
[^6]: A Control Hub toggle can automatically create RedSky E911 buildings and locations for Webex Calling locations; it is off by default for Webex Calling customers and on by default for Webex Wholesale. Source: [Enhanced emergency calling for Webex Calling](https://help.webex.com/en-us/article/av6oo3/Enhanced-emergency-calling-for-Webex-Calling), Control Hub and Locations. Checked 2026-09-24.
[^7]: E911 buildings (with full civic address) and locations within them (such as a floor or wing) are created in the RedSky administration portal, not in Control Hub. Source: [Enhanced emergency calling for Webex Calling](https://help.webex.com/en-us/article/av6oo3/Enhanced-emergency-calling-for-Webex-Calling), Configure E911 location wizard / Add E911 locations. Checked 2026-09-24.
[^8]: For Cisco Calling Plan, an emergency service address is mandatory and the location's ESA applies to all its phone numbers by default. Source: [Cisco Calling Plan](https://help.webex.com/en-us/article/nousk9ab/Cisco-Calling-Plan), Emergency service address. Checked 2026-09-24.
[^9]: On Cisco Calling Plan trial accounts emergency services are for technical evaluation only and actual emergency calls cannot be guaranteed. Source: [Cisco Calling Plan](https://help.webex.com/en-us/article/nousk9ab/Cisco-Calling-Plan), Emergency services limitations - trial accounts. Checked 2026-09-24.
[^10]: CDP is not supported for RedSky network discovery from the Webex App; LLDP, BSSID, IP address and gateway MAC are used instead. Source: [Enhanced emergency calling for Webex Calling](https://help.webex.com/en-us/article/av6oo3/Enhanced-emergency-calling-for-Webex-Calling), Location detection - HELD+ for Webex App. Checked 2026-09-24.
[^11]: Webex App on a mobile platform with a cellular connection does not use RedSky; emergency calls go through the native dialer over the cellular network. Source: [Enhanced emergency calling for Webex Calling](https://help.webex.com/en-us/article/av6oo3/Enhanced-emergency-calling-for-Webex-Calling), Deployment scenarios. Checked 2026-09-24.
[^12]: Anyone installing, managing or operating an MLTS in the US must configure it so users can dial 911 directly without any prefix such as a trunk-access 9. Source: [47 CFR § 9.16 - General obligations for MLTS (Cornell LII republication)](https://www.law.cornell.edu/cfr/text/47/9.16), 47 CFR 9.16(b)(1). Checked 2026-09-24.
[^13]: A dispatchable location is the validated street address of the caller plus information such as suite or apartment needed to adequately identify the caller's location. Source: [47 CFR § 9.3 - Definitions (Cornell LII republication)](https://www.law.cornell.edu/cfr/text/47/9.3), 47 CFR 9.3, 'Dispatchable location'. Checked 2026-09-24.
[^14]: An on-premises fixed telephone on an MLTS must provide automated dispatchable location, required no later than January 6, 2021. Source: [47 CFR § 9.16 - General obligations for MLTS (Cornell LII republication)](https://www.law.cornell.edu/cfr/text/47/9.16), 47 CFR 9.16(b)(3)(i). Checked 2026-09-24.
[^15]: MLTS operators must configure the system to send MLTS notification to a central location at the facility or to another person or organisation, where the system can do so without hardware or software improvement. Source: [47 CFR § 9.16 - General obligations for MLTS (Cornell LII republication)](https://www.law.cornell.edu/cfr/text/47/9.16), 47 CFR 9.16(b)(2). Checked 2026-09-24.
[^16]: MLTS notification must be initiated contemporaneously with the 911 call where technically feasible. Source: [47 CFR § 9.16 - General obligations for MLTS (Cornell LII republication)](https://www.law.cornell.edu/cfr/text/47/9.16), 47 CFR 9.16(b)(2)(i). Checked 2026-09-24.
[^17]: From January 6, 2022, an off-premises MLTS device must provide automatic dispatchable location if technically feasible, otherwise dispatchable location via manual update or enhanced location information. Source: [47 CFR § 9.16 - General obligations for MLTS (Cornell LII republication)](https://www.law.cornell.edu/cfr/text/47/9.16), 47 CFR 9.16(b)(3)(iii). Checked 2026-09-24.
[^18]: From January 6, 2022, an on-premises non-fixed MLTS device must provide automated dispatchable location when technically feasible, otherwise dispatchable location via manual user update or alternative location information. Source: [47 CFR § 9.16 - General obligations for MLTS (Cornell LII republication)](https://www.law.cornell.edu/cfr/text/47/9.16), 47 CFR 9.16(b)(3)(ii). Checked 2026-09-24.
[^19]: Control Hub's own emergency call notification sends an English-only email from a do-not-reply address to an organisation or location address when an emergency call is placed, and is disabled by default. Source: [Emergency call notifications in Control Hub](https://help.webex.com/en-us/article/nj0abhbb/Emergency-call-notifications-in-Control-Hub), Overview and limitations; Services > PSTN & Routing > Settings > Emergency call notification. Checked 2026-09-24.
[^20]: The location-level setting 'Allow RedSky to receive network connectivity information and test calls' lets MPP phones place calls to RedSky's emergency test number 933. Source: [Enhanced emergency calling for Webex Calling](https://help.webex.com/en-us/article/av6oo3/Enhanced-emergency-calling-for-Webex-Calling), Enable the E911 service for Webex Calling locations. Checked 2026-09-24.
[^21]: To create a new RedSky account from Control Hub, the admin enters the email to use as the RedSky administrator login and the partner's organisation ID. Source: [Enhanced emergency calling for Webex Calling](https://help.webex.com/en-us/article/av6oo3/Enhanced-emergency-calling-for-Webex-Calling), Create a new account. Checked 2026-09-24.
[^22]: A user whose primary number is a non-mobile US or Canadian number can be given a custom emergency service address that overrides the location default, under Management > Users > Calling > Numbers. Source: [Enhanced emergency calling for Webex Calling](https://help.webex.com/en-us/article/av6oo3/Enhanced-emergency-calling-for-Webex-Calling), Custom emergency service address. Checked 2026-09-24.
[^23]: DECT handsets and ATAs do not communicate with the RedSky service, so the RedSky portal needs a location associated with their caller ID. Source: [Enhanced emergency calling for Webex Calling](https://help.webex.com/en-us/article/av6oo3/Enhanced-emergency-calling-for-Webex-Calling), Enable the E911 service for Webex Calling locations. Checked 2026-09-24.
[^24]: Deleting a location in Control Hub does not automatically delete the corresponding building and location from the RedSky portal. Source: [Enhanced emergency calling for Webex Calling](https://help.webex.com/en-us/article/av6oo3/Enhanced-emergency-calling-for-Webex-Calling), Control Hub and Locations. Checked 2026-09-24.
[^25]: The location ECBN is set in Control Hub under Management > Locations > (location) > Calling > Emergency Callback Number, and the user ECBN under Management > Users > (user) > Calling > Emergency Callback Number. Source: [Emergency callback number in Control Hub](https://help.webex.com/en-us/article/nzqvtyq/Emergency-callback-number-in-Control-Hub), Configure ECBN for a location / for a user. Checked 2026-09-24.
[^26]: An emergency callback number can be the user's own number, the location's default ECBN, or another user, workspace, virtual line or hunt group number in the same location. Source: [Emergency callback number in Control Hub](https://help.webex.com/en-us/article/nzqvtyq/Emergency-callback-number-in-Control-Hub), Overview (three configuration options). Checked 2026-09-24.
[^27]: To link an existing RedSky account, the admin chooses to log in to the existing account and enters the partner administrator email, the partner administrator password and the RedSky Organization ID. Source: [Enhanced emergency calling for Webex Calling](https://help.webex.com/en-us/article/av6oo3/Enhanced-emergency-calling-for-Webex-Calling), Login to existing account. Checked 2026-09-24.
[^28]: At least one Webex Calling customer tells its users that E911 addresses in Webex App must be complete in standard US format and that calls without an assigned location delay response and incur a fee (field report). Source: [Webex E911](https://it.ufl.edu/infrastructure/telecommunications/instructional--informational-guides/softphone-webex/webex-e911), Adding / updating your address. Checked 2026-09-24.
[^29]: Networks must allow access to https://api.wxc.e911cloud.com and https://wxc.e911cloud.com for the RedSky integration. Source: [Enhanced emergency calling for Webex Calling](https://help.webex.com/en-us/article/av6oo3/Enhanced-emergency-calling-for-Webex-Calling), Requirements for E911 service integration with Webex Calling. Checked 2026-09-24.
[^30]: HELD-capable MPP devices report their network environment (upstream LLDP switch, wireless access point BSSID, IP address or MAC addresses) to RedSky using HTTP Enabled Location Delivery. Source: [Enhanced emergency calling for Webex Calling](https://help.webex.com/en-us/article/av6oo3/Enhanced-emergency-calling-for-Webex-Calling), Location detection. Checked 2026-09-24.
[^31]: HELD devices must be resynced or reinitialised to pick up the new configuration; otherwise a device may check for configuration updates within the next 24 hours. Source: [Enhanced emergency calling for Webex Calling](https://help.webex.com/en-us/article/av6oo3/Enhanced-emergency-calling-for-Webex-Calling), Enable the E911 service for Webex Calling locations. Checked 2026-09-24.
[^32]: Horizon Mobility accepts CSV imports for buildings, locations, device users, MAC/BSSID/LLDP assignments and IP ranges, and chassis data must be imported before ports. Source: [Control Hub - Enhanced 911 (E911) Emergency Services (RedSky)](https://webexcallingtraining.verizon.com/control-hub-redsky-emergency-911-service/), Step 3: CSV template import. Checked 2026-09-24.
[^33]: In the Horizon Mobility portal a wiremap maps locations to network elements such as IP subnets, network switches (chassis and ports) and access points. Source: [Control Hub - Enhanced 911 (E911) Emergency Services (RedSky)](https://webexcallingtraining.verizon.com/control-hub-redsky-emergency-911-service/), Step 2: Network discovery (wiremap creation). Checked 2026-09-24.
[^34]: At a RedSky-enabled location using a Local Gateway, emergency calls are sent to the E911 service instead of the local gateway, including from nomadic endpoints of users assigned to the location. Source: [Enhanced emergency calling for Webex Calling](https://help.webex.com/en-us/article/av6oo3/Enhanced-emergency-calling-for-Webex-Calling), Deployment scenarios - Local gateway and E911 service enabled locations. Checked 2026-09-24.
[^35]: At a Local Gateway location that is not RedSky-enabled, all calls including emergency calls are routed through the local gateway. Source: [Enhanced emergency calling for Webex Calling](https://help.webex.com/en-us/article/av6oo3/Enhanced-emergency-calling-for-Webex-Calling), Deployment scenarios - multinational example (Location A). Checked 2026-09-24.
[^36]: Enabling Enhanced Emergency Calling on a Webex Calling location (Management > Locations > Calling) and saving changes the location state to Location Integration On. Source: [Enhanced emergency calling for Webex Calling](https://help.webex.com/en-us/article/av6oo3/Enhanced-emergency-calling-for-Webex-Calling), Enable the E911 service for Webex Calling locations. Checked 2026-09-24.
[^37]: The Control Hub wizard warns that if building and location details are not added in RedSky, emergency calls are re-routed to relay centres. Source: [Enhanced emergency calling for Webex Calling](https://help.webex.com/en-us/article/av6oo3/Enhanced-emergency-calling-for-Webex-Calling), Configure E911 location wizard - Update service settings. Checked 2026-09-24.
[^38]: HELD-capable MPP phones do not let the user hang up an emergency call; the far end must release it, and the phone can be manually reset to release the line if needed. Source: [Enhanced emergency calling for Webex Calling](https://help.webex.com/en-us/article/av6oo3/Enhanced-emergency-calling-for-Webex-Calling), Enable the E911 service for Webex Calling locations. Checked 2026-09-24.
[^39]: MPP devices do not allow mid-call features such as hold, conference and transfer on emergency calls. Source: [Enhanced emergency calling for Webex Calling](https://help.webex.com/en-us/article/av6oo3/Enhanced-emergency-calling-for-Webex-Calling), Deployment scenarios. Checked 2026-09-24.
[^40]: When a nomadic user takes Webex App to an off-premises network, the app prompts the user to enter a dispatchable address. Source: [Enhanced emergency calling for Webex Calling](https://help.webex.com/en-us/article/av6oo3/Enhanced-emergency-calling-for-Webex-Calling), Location detection - nomadic users. Checked 2026-09-24.
[^41]: When a user reconnects to an off-premises network for which they already provided an address, Webex App reuses that address automatically. Source: [Enhanced emergency calling for Webex Calling](https://help.webex.com/en-us/article/av6oo3/Enhanced-emergency-calling-for-Webex-Calling), Location detection - nomadic users. Checked 2026-09-24.
[^42]: For non-HELD-capable devices, RedSky determines location from the caller ID asserted in the test or emergency call. Source: [Enhanced emergency calling for Webex Calling](https://help.webex.com/en-us/article/av6oo3/Enhanced-emergency-calling-for-Webex-Calling), Requirements for E911 service integration with Webex Calling. Checked 2026-09-24.
[^43]: Cisco recommends that non-HELD devices are not moved between locations without administrator approval. Source: [Enhanced emergency calling for Webex Calling](https://help.webex.com/en-us/article/av6oo3/Enhanced-emergency-calling-for-Webex-Calling), Requirements for E911 service integration with Webex Calling. Checked 2026-09-24.
[^44]: Control Hub offers an option to opt the organisation out of the RedSky service when the PSTN provider handles emergency calling, in which case telephone-number-based emergency service (emergency callback number) applies. Source: [Enhanced emergency calling for Webex Calling](https://help.webex.com/en-us/article/av6oo3/Enhanced-emergency-calling-for-Webex-Calling), Opt this Organization out. Checked 2026-09-24.
[^45]: The organisation-level RedSky setup is reached in Control Hub under Services > PSTN & Routing > Settings > Enhanced Emergency Calling. Source: [Enhanced emergency calling for Webex Calling](https://help.webex.com/en-us/article/av6oo3/Enhanced-emergency-calling-for-Webex-Calling), Create a new account / Enable E911 service for your organization. Checked 2026-09-24.
[^46]: A Verizon training guide places the organisation-level Enhanced Emergency Calling toggle under Calling > Service Settings in Control Hub, which differs from Cisco's current article (disputed). Source: [Control Hub - Enhanced 911 (E911) Emergency Services (RedSky)](https://webexcallingtraining.verizon.com/control-hub-redsky-emergency-911-service/), Step 5: Control Hub verification. Checked 2026-09-24.
[^47]: A computer connected through a phone's pass-through port cannot read the switch's LLDP information because LLDP frames stop at the phone. Source: [Enhanced emergency calling for Webex Calling](https://help.webex.com/en-us/article/av6oo3/Enhanced-emergency-calling-for-Webex-Calling), Location detection - HELD+ for Webex App. Checked 2026-09-24.
[^48]: Phones and the Webex client communicate with the RedSky service over port 443. Source: [Enhanced emergency calling for Webex Calling](https://help.webex.com/en-us/article/av6oo3/Enhanced-emergency-calling-for-Webex-Calling), Requirements for E911 service integration with Webex Calling. Checked 2026-09-24.
[^49]: At a RedSky-enabled location using PSTN service, emergency calls from all endpoints (hard phones and portable endpoints) are sent to the E911 service instead of the configured PSTN. Source: [Enhanced emergency calling for Webex Calling](https://help.webex.com/en-us/article/av6oo3/Enhanced-emergency-calling-for-Webex-Calling), Deployment scenarios - PSTN and E911 service enabled locations. Checked 2026-09-24.
[^50]: On-site emergency call alerts for the RedSky integration are configured in the RedSky administration portal and can go to recipients by email, SMS or a desktop application. Source: [Enhanced emergency calling for Webex Calling](https://help.webex.com/en-us/article/av6oo3/Enhanced-emergency-calling-for-Webex-Calling), Configure E911 location wizard - Set up alerts. Checked 2026-09-24.
[^51]: Relay centre call costs are passed back to the customer when the user had not provided an emergency address in Webex App or configuration was incorrect. Source: [Enhanced emergency calling for Webex Calling](https://help.webex.com/en-us/article/av6oo3/Enhanced-emergency-calling-for-Webex-Calling), Location detection. Checked 2026-09-24.
[^52]: If the E911 service cannot find a dispatchable location for a device placing an emergency call, the call goes to an emergency calling relay centre whose agent works with the caller to route it. Source: [Enhanced emergency calling for Webex Calling](https://help.webex.com/en-us/article/av6oo3/Enhanced-emergency-calling-for-Webex-Calling), Location detection. Checked 2026-09-24.
[^53]: Turning off 'Route Emergency Calls to RedSky' on a location is the reversal of the final step, and emergency calls would then presumably follow the location's normal PSTN or Local Gateway path with telephone-number-based handling (inferred). Source: [Enhanced emergency calling for Webex Calling](https://help.webex.com/en-us/article/av6oo3/Enhanced-emergency-calling-for-Webex-Calling), Inferred from 'Enable the E911 service for Webex Calling locations' and 'Deployment scenarios'. Checked 2026-09-24.
[^54]: After test calls are confirmed, turning on 'Route Emergency Calls to RedSky' for the location and saving changes its state to Routing On. Source: [Enhanced emergency calling for Webex Calling](https://help.webex.com/en-us/article/av6oo3/Enhanced-emergency-calling-for-Webex-Calling), Enable the E911 service for Webex Calling locations. Checked 2026-09-24.
[^55]: The Webex Calling enhanced emergency calling (RedSky) service applies to Webex Calling locations in the United States, its territories and Canada; locations elsewhere keep standard PSTN emergency handling. Source: [Enhanced emergency calling for Webex Calling](https://help.webex.com/en-us/article/av6oo3/Enhanced-emergency-calling-for-Webex-Calling), Overview and 'Deployment scenarios' (multinational example). Checked 2026-09-24.
[^56]: A 933 test call connects the caller to an IVR that announces the caller ID and the currently known address for that device. Source: [Enhanced emergency calling for Webex Calling](https://help.webex.com/en-us/article/av6oo3/Enhanced-emergency-calling-for-Webex-Calling), Enable the E911 service for Webex Calling locations. Checked 2026-09-24.
[^57]: Test calls can be placed from every endpoint assigned to the location, including HELD-capable devices, soft phones and non-HELD devices. Source: [Enhanced emergency calling for Webex Calling](https://help.webex.com/en-us/article/av6oo3/Enhanced-emergency-calling-for-Webex-Calling), Enable the E911 service for Webex Calling locations. Checked 2026-09-24.
[^58]: The RedSky integration is provisioned and validated in two independent portals: Control Hub and the RedSky administration portal. Source: [Enhanced emergency calling for Webex Calling](https://help.webex.com/en-us/article/av6oo3/Enhanced-emergency-calling-for-Webex-Calling), Integration overview (provisioning standpoint paragraph). Checked 2026-09-24.
[^59]: Webex Calling users in the US are entitled to the RedSky E911 service with their Webex Calling entitlement; users in Canada need a RedSky license. Source: [Enhanced emergency calling for Webex Calling](https://help.webex.com/en-us/article/av6oo3/Enhanced-emergency-calling-for-Webex-Calling), Requirements for E911 service integration with Webex Calling. Checked 2026-09-24.
[^60]: The wiremap built in the RedSky portal associates network elements with the E911 locations, and location configuration there is required for RedSky to detect caller locations. Source: [Enhanced emergency calling for Webex Calling](https://help.webex.com/en-us/article/av6oo3/Enhanced-emergency-calling-for-Webex-Calling), Configure E911 location wizard - Configure network elements. Checked 2026-09-24.
[^61]: The Control Hub E911 wizard requires the admin to confirm that alerts were set up in the E911 administration portal, stating that FCC regulations require an emergency response team to be notified of 911 calls. Source: [Enhanced emergency calling for Webex Calling](https://help.webex.com/en-us/article/av6oo3/Enhanced-emergency-calling-for-Webex-Calling), Configure E911 location wizard - Set up alerts. Checked 2026-09-24.
[^62]: The Control Hub 'Configure E911 location' wizard walks through updating service settings, setting up alerts, configuring network elements and enabling emergency calling, each requiring confirmation that the matching RedSky portal work is done. Source: [Enhanced emergency calling for Webex Calling](https://help.webex.com/en-us/article/av6oo3/Enhanced-emergency-calling-for-Webex-Calling), Configure E911 location wizard. Checked 2026-09-24.
[^63]: US Webex Calling users receive the RedSky entitlement at no additional charge. Source: [Enhanced Emergency Calling for Webex Calling](https://help.webex.com/en-us/article/av6oo3/Enhanced-Emergency-Calling-for-Webex-Calling), article overview; licensing and cost statement. Checked 2026-09-24.
[^64]: RedSky location detection for Webex Calling does not support VPN; VPN interfaces are filtered out. Source: [Enhanced Emergency Calling for Webex Calling](https://help.webex.com/en-us/article/av6oo3/Enhanced-Emergency-Calling-for-Webex-Calling), limitations section. Checked 2026-09-24.