2section (Continued) 6 Layer 3 Processing

2.6.4.1.2.1 Use of Variables

The mobile station shall maintain a service request sequence number variable, SERV_REQ_NUM_s for use with service negotiation. Upon entering the Mobile Station Control On the Traffic Channel State, the mobile station shall set SERV_REQ_NUM_s to 0. Each time the mobile station sends a new Service Request Message, it shall set the SERV_REQ_SEQ field of the message to the current value of SERV_REQ_NUM_s, and shall then set SERV_REQ_NUM_s equal to (SERV_REQ_NUM_s + 1) modulo 8.

2.6.4.1.2.1.2 Maintaining the Service Negotiation Indicator Variable

The mobile station shall maintain a service negotiation indicator variable, SERV_NEG_s, to indicate which type of negotiation to use, either service negotiation or service option negotiation. The mobile station shall set SERV_NEG_s to enabled whenever service negotiation is to be used, and shall set SERV_NEG_s to disabled whenever service option negotiation is to be used. The precise rules for setting SERV_NEG_s are specified in 2.6.4.2 and 2.6.6.2.5.1.

For CDMA operation in band classes other than Band Class 0, the mobile station shall set SERV_NEG_s to enabled.

2.6.4.1.2.1.3 Maintaining the Service Option Request Number

The mobile station shall maintain a service option request number variable, SO_REQ_s, for use with service option negotiation. The mobile station shall set SO_REQ_s to a special value, NULL, if the mobile station does not have an outstanding service option request. If the mobile station has an outstanding service option request, the mobile station shall set SO_REQ_s to the number of the service option associated with the outstanding request.

2.6.4.1.2.1.4 Stored Service Configuration and Reconnection

This section provides an overview of how the mobile station and the base station may store the service configuration and how the stored service configuration may be restored upon re-establishing dedicated channels.

Upon establishing a call and entering the Mobile Station Control on the Traffic Channel State, service negotiation procedures are performed as specified in 2.6.4.1.2.2 to establish a mutually acceptable service configuration between the mobile station and the base station. The service configuration consists of parameters specified via the Service Configuration information record (see 3.7.5.7) and Non-Negotiable Service Configuration information record (see 3.7.5.20). The mobile station and the base station may store the established service configuration. This is done so that when the call is re-established, the stored service configuration may be restored and without performing the service negotiation procedures. In order to ensure that the service configuration restored at the mobile station and the base station are identical (that is, the values of the service configuration parameters are identical), a service configuration synchronization identifier (called SYNC_ID) is associated with each stored service configuration. SYNC_ID is a variable length identifier assigned by the base station corresponding to a particular Service Configuration information record and Non-negotiable Service Configuration information record. The SYNC_ID value is used by the base station to determine whether these two information records may be omitted from the Service Connect Message.

When P_REV_IN_USE_s is less than or equal to six, there is no requirement on storing the established service configuration for future use. In this case, when a call is re-established and the mobile station enters the Mobile Station Control on the Traffic Channel State, service configuration must be re-established by performing service negotiation procedures again.

When P_REV_IN_USE_s is greater than six, based on the value of SYNC_ID included by the mobile station in the Origination Message, Page Response Message, or Enhanced Origination Message the base station may not send the Service Configuration information record and the Non-negotiable Service Configuration information record over the air and instructs the mobile station to start using the stored information records corresponding to the SYNC_ID reported by the mobile station.

When P_REV_IN_USE_s is equal to or greater than nine, the mobile station is required to store minimum of four service configurations. Also, the stored service configuration can be restored incrementally as well. That is, if N service option connections are contained in the stored service configuration, then the mobile station can request to restore one of these service option connections upon establishing dedicated channels. This is achieved via the SR_ID field of the Origination Message or Reconnect Message. Once operating on the dedicated channels, the mobile station can request to restore additional service option connections via the Enhanced Origination Message. The base station in turn can grant the mobile station request via Extended Channel Assignment Message, Service Connect Message, or Call Assignment Message. If the base station uses Extended Channel Assignment Message to grant the mobile station request, then the base station is not required to send a Service Connect Message. During traffic channel operation, service option connections are to be restored only from the SYNC_ID that is currently in use (if any).

When P_REV_IN_USE_s is equal to or greater than 11, the base station can autonomously order the mobile station to restore a stored service configuration via the Extended Channel Assignment Message or Service Connect Message even when the mobile station has not requested to restore a service configuration, or when the mobile station has requested to restore a different service configuration. Additionally, the base station can signal the SYNC_ID value corresponding to the currently used service configuration using the Universal Handoff Direction Message.