name: LSM
full_form: Limited Service Mode
context: UEs that are in limited service mode (LSM) and that cannot be authenticated by the MME (for whatever reason) may still be allowed to establish emergency calls by sending the emergency attach request message. It shall be possible to configure whether the MME allows unauthenticated UEs in LSM to establish bearers for emergency calls or not. If an MME allows unauthenticated UEs in LSM to establish bearers for an emergency call, the MME shall for the NAS protocol use EIA0 and EEA0 as the integrity and ciphering algorithm respectively. If the MME allows an unauthenticated UE in LSM to establish bearers for emergency calls after it has received the emergency attach request message from the UE, the MME shall: - Select EIA0 and EEA0, regardless of the supported algorithms announced previously by the UE as the NAS algorithms and signal this to the UE via the NAS security mode command procedure when activating the EPS NAS security context. - Set the UE EPS security capabilities to only contain
description: Limited Service Mode (LSM) is an operational state of a User Equipment (UE) where it has restricted access to network services, but may still be allowed to establish emergency calls under specific conditions.
explanation: The text describes LSM as a specific operational state or condition for a User Equipment (UE), restricting its service capabilities. This aligns with the definition of 'Mode' as an operational state or condition of a network element or procedure.
section_title: 7.2.4a	Algorithm negotiation for unauthenticated UEs in LSM
biotag_Context: B-Device,O,O,O,O,O,O,O,O,O,O,O,O,O,O,B-Network Function,O,O,O,O,O,O,O,O,O,O,O,O,O,O,O,O,O,O,O,O,O,O,O,O,O,O,B-Network Function,O,O,B-Device,O,B-Mode,O,O,O,O,O,O,O,O,O,O,B-Network Function,O,O,B-Device,O,B-Mode,O,O,O,O,O,O,O,O,B-Network Function,O,O,O,B-Protocol,O,O,B-Miscellaneous,O,B-Miscellaneous,O,O,O,O,O,O,O,O,O,B-Network Function,O,O,O,B-Device,O,B-Mode,O,O,O,O,O,O,O,O,O,O,O,O,O,O,O,O,O,O,O,B-Network Function,O,O,O,B-Miscellaneous,O,O,O,O,O,O,O,O,O,O,O,B-Device,O,O,B-Protocol,O,O,O,O,O,O,B-Device,O,O,B-Protocol,O,O,O,O,O,O,O,B-Network,B-Protocol,O,O,O,O,O,B-Device,B-Network,O,O,O,O,O
biotag_Description: B-Mode,I-Mode,I-Mode,O,O,O,O,O,O,O,B-Device,I-Device,O,O,O,O,O,O,O,O,O,O,O,O,O,O,O,O,O,O,O,O,O