tokens: ['the', 'Trigger', 'Detection', 'Point', 'criteria', 'for', 'both', 'call', 'related', 'and', 'call', 'unrelated', 'service', 'triggering', 'VPN', 'notification', 'VPNNO', 'It', 'shall', 'be', 'possible', 'for', 'an', 'SSF', 'to', 'notify', 'an', 'SCF', 'providing', 'an', 'IN', 'VPN', 'service', 'that', 'the', 'use', 'of', 'the', 'network', 'capability', 'to', 'transport', 'PSS', 'signalling', 'enhancements', 'to', 'basic', 'call', 'is', 'present', 'in', 'the', 'received', 'call', 'request', 'message', 'VPN', 'control', 'VPNCO', 'An', 'SCF', 'providing', 'an', 'IN', 'VPN', 'service', 'shall', 'be', 'able', 'to', 'instruct', 'the', 'SSF', 'to', 'prohibit', 'or', 'allow', 'the', 'use', 'of', 'the', 'network', 'capability', 'to', 'transport', 'PSS', 'signalling', 'enhancements', 'to', 'basic', 'call', 'When', 'this', 'control', 'is', 'used', 'the', 'VPN', 'with', 'the', 'PSS', 'APM', 'is', 'correctly', 'terminated', 'and', 'the', 'SCF', 'and', 'SSF', 'shall', 'cooperate', 'to', 'provide', 'outgoing', 'gateway', 'PINX', 'functionality', 'according', 'to', 'PSS', 'information', 'flows', 'If', 'this', 'control', 'is', 'not', 'used', 'Transit', 'PINX', 'is', 'the', 'default', 'functionality', 'Personal', 'and', 'terminal', 'mobility', 'support', 'Dynamic', 'TriggerDetectionPoint', 'activationdeactivation', 'DTDPA', 'It', 'shall', 'be', 'possible', 'to', 'activatedeactivate', 'several', 'existing', 'TDPs', 'in', 'the', 'SSF']