Section: 4.3.12.9 Handling of PDN Connections for Emergency Bearer Services
Content: The default and dedicated EPS bearers of a PDN Connection associated with the emergency APN shall be dedicated for IMS emergency sessions and shall not allow any other type of traffic. The emergency bearer contexts shall not be changed to non-emergency bearer contexts and vice versa. The PDN GW shall block any traffic that is not from or to addresses of network entities (e.g. P-CSCF) providing IMS emergency service. Dynamic PCC shall be deployed in order to support IMS emergency sessions, the procedures are as described in TS 23.203[ Policy and charging control architecture ]  [6]. If there is already an emergency PDN GW connection, the UE shall not request another emergency PDN Connection. The MME shall reject any additional emergency PDN Connection requests. The UE shall not request any bearer resource modification for the emergency PDN connection. The PDN GW shall reject any UE requested bearer resource modification that is for the emergency PDN Connection. The ARP reserved for emergency bearer service shall only be assigned to EPS bearers associated with an emergency PDN Connection.