4.5. Error handling

The following sections defines how errors should be handled.

4.5.1. Unknown component

If the component (cId) is not known, then the site must answer with CommandResponse/StatusResponse where the values are set according to the table below.

Table 4.28 ComponentId unknown
Message type	Element	Value
StatusResponse	q	undefined
StatusResponse	s	`null`
CommandResponse	age	undefined
CommandResponse	v	`null`

4.5.2. SXL mismatch

If there is a mismatch of the SXL when receiving a command, status or alarm request, which is not caught during communication handshake (See RSMP/SXL Version), then this is considered a serious error resulting in MessageNotAck.

This includes:

unknown alarm/status/command code id (aCId, sCI, cCI) for the corresponding object type
unknown name (n) in arguments or return values

4.5.3. Unimplemented statuses or commands

If a status (sCI) or command (cCI) is recognized in relation to its SXL but not unimplemented, the site answers with CommandResponse/StatusResponse where the values are set according to the table below.

Table 4.29 Unimplemented
Message type	Element	Value
StatusResponse	q	unknown
StatusResponse	s	`null`
CommandResponse	age	unknown
CommandResponse	v	`null`

4.5.4. Incomplete commands

If not all arguments are included in a CommandRequest, then this is considered a serious error resulting in MessageNotAck.

4.5.5. More than one command

If more than one command (cCI) is included in a single CommandRequest or CommandResponse, then this is considered a serious error resulting in MessageNotAck.