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OpenScape First Response ESINet/NGCS Solution

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The OpenScape First Response ESInet/NGCS Solution is made up of a number of components that provide the Next-Generation Core Services (NGCS) for an emergency calling network. Typical customers for this solution would be national or regional government entities responsible for handling requests for emergency service (Police, Fire, Emergency Medical, etc.).

All OpenScape First Response ESInet/NGCS solution components are implemented based on both North American (NENA) and European (ETSI/EENA) standards and can be deployed anywhere in the world.

The OpenScape First Response ESInet/NGCS Solution consists of the following functional elements:

Border Control Function (BCF)

The OpenScape Border Control Function sits between external networks and the Emergency Services IP Network (ESInet) and provides a secure entry into the ESInet for emergency calls (and other calls) presented to the network. All traffic from external networks transits a BCF. The BCF incorporates firewall, admission control and session and media anchoring, as well as other security mechanisms to prevent deliberate or malicious attacks on Public Safety Answering Points (PSAPs) or other entities connected to the ESInet.

Typically, separate BCFs will be used on the ingress and egress sides of the ESInet. The BCF on the ingress side is referred to as the BCF-I and the BCF on the egress side is the BCF-E.


Emergency Services Routing Proxy (ESRP)

The OpenScape First Response Emergency Services Routing Proxy is based on the OpenScape Voice and sits within the ESInet and provides emergency call routing services. An emergency call arrives at an ESRP from a Border Control Function (BCF) or another ESRP. An ESRP makes routing decisions based on information in the incoming INVITE message (typically including the caller’s location or a reference to the caller’s location), on information returned from location and routing databases such as the LIS and ECRF, and the routing policies in effect at the time of the call. The ESRP makes what is referred to as a ‘next-hop’ decision and routes the call to a Public Safety Answering Point (PSAP) or another ESRP for further routing.

Media Service Bridge Function (MSBF)

The OpenScape First Response Media Service Bridge Function supports conferencing and bridging applications. The MSBF includes special functions for text conferencing; in the case where a PSAP that received a text-to-9-1-1 call transfers that call to a different PSAP, the MSBF will provide the entire contents of the text conversation to the transferred-to-PSAP. The MSBF can also support digit collection and IVR capabilities.


Policy Store Service (PSS)

The OpenScape First Response Policy Store Service is a database of routing policies. Routing policies are used by the Policy Routing Function (PRF) component of an ESRP according to NENA and ETSI/EENA standards. ESRPs query the PSS for routing policy information as needed for call handling activities.


A routing policy – sometimes also referred to as a ruleset – is a set of rules to be applied when an ESInet is attempting to route a call. Two types of routing policies exist; originating policies and terminating policies. Originating policies apply to a call up until the point at which an intended destination PSAP is determined for that call (typically by receiving a normal-next-hop URL in response to a query to the ECRF). Originating policies will consider such parameters as where the call originated from, the suspicion level of the call, message contents and MIMEs, etc.

A terminating policy is applied once a default destination PSAP has been determined. A policy or ruleset should exist for every PSAP connected to an ESInet, and will consider such parameters as time-of-day, PSAP state, call type, message content and MIMEs, etc.

The Policy Store Service will contain all routing policies for an ESInet and may serve multiple ESRPs.


Legacy PSAP Gateway (LPG)

OpenScape First Response BCF contains additional features that allow it to function as a Legacy PSAP Gateway.

A Legacy PSAP Gateway is used to connect PSAPs that are not fully next-generation compliant to a next-generation compliant ESInet. An LPG performs three functions:

  • NIF (next-Generation Specific Interworking Function) - this provides special processing received information to facilitate call delivery to legacy PSAP
  • PIF (Protocol Interworking Function) - this is the conversion of the SIP as used in the NGCS to the appropriate protocol (e.g. CAMA trunk) needed by the legacy PSAP equipment. This is normally provided by a third-party device.
  • LIF (Location Interworking Function) - this component provides interworking between next-generation location delivery technologies and the legacy PSAP.

Once the Legacy PSAP equipment has been upgraded to be next-generation compliant, the LPG will no longer be needed.


Emergency Services Application (ESAPP)

The OpenScape First Response Emergency Services Application provides a mechanism for PSAPs which do not have built-in text call handling capabilities to receive and process text calls by interfacing with a web application. This is referred to as an 'over-the-top' (OTT) function.

Text calls destined for PSAPs without integrated text-call handling capabilities are sent to the ESAPP (via the BCF-E) and are then sent to a third-party web server that can be accessed by call-takers at the intended PSAPs.

If all PSAPs served by the ESInet have integrated text-call handling capabilities, the Emergency Services Application (and the third-party web server) are not required.

Note that the ESAPP is only intended for use within North America at this time.


Next Generation Logging Service (NGLS)

The OpenScape First Response Next Generation Logging Service is a functional element that can be a component of both the OpenScape First Response NGCS solution and the OpenScape First Response PSAP solution.

As part of the NGCS solution, the NGLS provides event logging and reporting capabilities as specified in the NENA standards.

As part of the PSAP solution, the NGLS provides a set of reports (both pre-defined and ad-hoc) on all call-handling activities that take place at a PSAP.

The NGLS has a multi-layer access control system, so reports can be generated on the basis of a single PSAP or a group of PSAPs.

The logging functionality defined by NENA is not reflected in the ETSI/EENA standards, so the NGLS is typically only used in North America.