Product specifications

Dialogic® BorderNet™ 4000 SBC Product Description Document

• If the message is a response message, the BorderNet 4000 SBC parses the next

header.

• If the message includes a resource-priority header, the response is parsed and

handled.

Emergency Call Handling

The BorderNet 4000 SBC ensures that emergency sessions are always handled, even under

the most severe level of system overload. Priority levels defined by the ETS namespace

values (RFC 4412) are supported in the following priority order:

• ets.0 (highest priority)

• ets.1

• ets.2

• ets.3

• ets.4 (lowest priority)

The BorderNet 4000 SBC recognizes emergency calls by the INVITE message. If the INVITE

message contains the resource-priority header with one of the ETS priority levels (ets.0 –

ets.4), that message is handled. If the INVITE message contains a To-URI or a Request-URI

that contains a match in the Emergency URI Configuration Table, that message is handled.

SIP URN Routing for Emergency Services

The BorderNet 4000 SBC supports call routing based on the service URN concept proposed

in RFC 5031 to handle emergency and other context-sensitive scenarios. Regulatory bodies

and leading emergency associations such as the National Emergency Number Association

(NENA) have adopted the SIP URN scheme in their next-generation architecture and

standards documents. Some example of SIP URN for emergency services include:

urn:service:sos.ambulance, urn:service:sos.fire, urn:service:sos.police,

urn:service:sos.poison. In this scheme, emergency routing is more efficient. Using the

available service and subservice context, each call is routed to appropriate first responders.

This has an additional benefit of removing region-specific emergency service access (for

example, 911 in US, 112 in Europe, or 100 in India) by utilizing a common naming

convention.

The BorderNet 4000 SBC is typically deployed as a Border Control Function (BCF) in an

Emergency Service Network (ESINet). In this role, the BorderNet 4000 SBC provides core

SBC functions such as security, call routing, call prioritization. The BorderNet 4000 SBC can

effectively support next generation ESINets by providing the capability to process

emergency calls with SIP URN and routing those calls based on URN’s service/subservice

context. Furthermore, the BorderNet 4000 SBC is also capable of modifying ToS (Type of

Service) bytes for emergency calls to ensure expeditious handling of emergency calls by

network switching and routing infrastructure.