Specification Compliance

The document entitled Conveyance of Emergency Incident Data Objects (EIDOs) between Next Generation (NG 9-1-1) Systems and Applications (NENA-STA-024.1a-2023) specifies the requirements for the transport of EIDOs between systems.

The Ng911CadIfLib class library implements a simplified set of requirements appropriate for the interface between a PSAP system and a CAD system. The following table indicates which portions of the NENA standard this class library supports.

NENA-STA-024 Section No.	Section Title	Supported?	Description
2.1.1	General Description	Partial	See General Requirements below
2.1.2	URI Scheme	Yes
2.1.3.1.1	Negotiate Web Socket	Yes
2.1.3.1.2	HTTP Headers	Yes
2.1.4	Client Web Socket API Actions	NA	Not Applicable
2.1.5	Objects	Yes
2.1.6	Notification Model	Yes
2.2	Min Rates and Max Rates In Detail	Partial	Support for Min Rates is provided. Max Rates support is not required.
2.3	qualFilter	No	The intended use of the Ng911CadIfLib class library is for communication between a single agency’s PSAP CHFE and that agency’s CAD system so EIDO filtering will not be required.
2.4	Transport in Call Signaling	No	Not Applicable
2.5	EIDO Dereference Factory	No
2.6	EIDO Dereference Service	No
2.7	EIDO Retrieval Service	Yes
2.8	Data Rights Management	No
2.9	Logging	Yes
2.10	Security	Partial	TLS with mutual authentication using PCA issued certificates is supported. Digital Rights Management is not supported.

NENA-STA-024.1a-2023 General Requirements

Section 2.1.1 of NENA-STA-024.1a-2023 specifies various general requirments for the EIDO conveyance protocol. The following table indicates which of these requirments are supported by the Ng911CadIfLib class library.

Section 2.1.1 Requirement	Supported?	Description
The Ng911CadIfServer class shall support Mutual authentication with credentials traceable to the PSAP Credentialing Agency (PCA)	Yes
For interoperability, all implementations SHALL accept subscription requests of any size up to and including 65,536 bytes.	Yes
All communication related to a subscription is handled over the Web Socket.	Yes
Upon successful subscription, notifications SHALL be sent to the subscriber as they match the criteria associated with the subscription until the subscription expires or client unsubscribes.	No	The Ng911CadIfServer class library does not support EIDO filtering.
The server shall accept subscriptions for new incidents or for a single incident.	Yes
For a new incidents subscription, a notification SHALL be sent immediately that contains all active incidents that match the criteria.	Yes
For a subscription for new incidents, if there are no EIDOs that match the criteria of the new subscription request, the server shall send an empty notification message.	Yes
A Single Incident subscription SHALL be accepted for a closed incident if the request is made within five minutes of its closure, in which case a single EIDO representing the last state of that incident SHALL be sent and no further notifications will be made for that incident. The server shall only accept changes to a subscription that changes the expiration of the subscription.	No
Once established, a Web Socket SHALL handle multiple subscriptions.	Yes	Only a single subscription per Web Socket needs to be supported because EIDO filtering is not required. If the Ng911CadIfServer object receives a new subscription request when a subscription already exists, it shall terminate the existing subscription and accept the new subscription.
Upon expiration of the last subscription still in effect the server will close the Web Socket. It is up to the subscriber to detect this closure and act appropriately	Yes
If the Web Socket is closed (including if the underlying TCP socket is closed) then the server shall flush all subscriptions established using that Web Socket without notifying the subscriber.	Yes