When emergency calls (for example, calls to 911) are received, the SBC Core recognizes them and proceeds to route them directly without any check for provisioned services. For proper routing to occur, an emergency routing label, emergency routes, and an emergency standard route entity must be provisioned.
The SBC supports configuring up to 32 emergency number prefixes and up to 10 service URNs in an Emergency Call Profile. If an incoming SIP INVITE has a R-URI with a prefix that matches one of the configured prefixes, or the R-URI contains a service URN configured in the urnPrefix table, the SBC treats the INVITE as an emergency session establishment.
% set profiles services emergencyCallProfile <profile name> cpc <none | priority> prefix <prefix> resPriorityHeaderProfile <profile name> sosInContactOfRegister <disable | enable> urnPrefix <prefix> xemg <disabled | enabled>
The Emergency Call Profile Parameters are as shown:
Emergency Call Profile Parameters
Parameter | Length/Range | Description |
---|---|---|
| 1-23 | The emergency call profile name. |
| N/A | This parameter controls the SBC behavior for whether to use SIP cpc=priority as emergency call indicator.
|
| 1-15 | An alphanumeric string representing an Emergency prefix for this Emergency Call Profile. Up to 32 Emergency prefixes may be configured. An incoming SIP call is classified as an emergency call if the called number matches this prefix. |
resPriorityHeaderProfile | 1-23 | The name of the existing Resource Priority Header (RPH) profile used for classifying a call as an emergency call based on RPH in the initial ingress INVITE. |
| N/A | A registration received with a "sos" parameter in the contact header is considered an emergency registration if it is enabled on the emergency call profile configured on the ingress trunk group. Enable flag to support this feature.
|
| 1-27 | Emergency prefix URN. For example, "service:sos" or "service:sos.police", where "police" is a subservice. |
| N/A | Use this flag to determine whether SIP X-EMG header should be accepted as an emergency call indicator.
|
The following example creates an Emergency Call Profile named "EmergCall-1", and specifies to use 'cpc=priority' as emergency call indicator. Also, "911" is set as an Emergency prefix so that any incoming call with a prefix of "911" is classified as an emergency call. The flag sosInContactOfRegister
is enabled as well.
% set profiles services emergencyCallProfile EmergCall-1 cpc priority prefix 911 resPriorityHeaderProfile RPHProfile sosInContactOfRegister enable % show profiles services emergencyCallProfile emergencyCallProfile EmergCall-1 { prefix 911; cpc priority; resPriorityHeaderProfile RPHProfile; sosInContactOfRegister enable; }