NetworkStatusResponse : NetworkStatusResponse contains basic information about the node’s view of a blockchain network. It is assumed that any BlockIdentifier.Index less than or equal to CurrentBlockIdentifier.Index can be queried. If a Rosetta implementation prunes historical state, it should populate the optional oldest_block_identifier field with the oldest block available to query. If this is not populated, it is assumed that the genesis_block_identifier is the oldest queryable block. If a Rosetta implementation performs some pre-sync before it is possible to query blocks, sync_status should be populated so that clients can still monitor healthiness. Without this field, it may appear that the implementation is stuck syncing and needs to be terminated.