tokens: ['enhanced', 'signalling', 'telling', 'the', 'UE', 'in', 'a', 'secure', 'way', 'about', 'the', 'country', 'it', 'is', 'in', 'However', 'the', 'two', 'attack', 'variants', 'described', 'for', 'the', 'circumvention', 'attack', 'either', 'assume', 'GERAN', 'access', 'or', '', 'where', 'integrityprotected', 'signalling', 'is', 'not', 'available', 'Therefore', 'network', 'signalling', 'would', 'not', 'help', 'How', 'could', 'networkindependent', 'location', 'verification', 'be', 'realised', 'GPS', 'Many', 'UEs', 'have', 'GPS', 'receivers', 'today', 'that', 'provide', 'a', 'networkindependent', 'means', 'of', 'location', 'verification', 'Pros', 'and', 'Cons', 'The', 'measure', 'is', 'effective', 'if', 'the', 'GPS', 'signal', 'is', 'genuine', 'But', 'unfortunately', 'research', 'suggests', 'that', 'GPS', 'spoofing', 'is', 'possible', 'cf', 'httpphysorgnewshtml', '', 'It', 'is', 'not', 'clear', 'todate', 'whether', 'future', 'implementations', 'of', 'GPS', 'in', 'UEs', 'can', 'prevent', 'such', 'spoofing', 'Furthermore', 'low', 'end', 'phones', 'are', 'less', 'likely', 'to', 'feature', 'GPS', 'receivers', 'User', 'involvement', 'Users', 'can', 'be', 'expected', 'to', 'know', 'in', 'which', 'country', 'they', 'currently', 'are', 'Hence', 'when', 'the', 'UE', 'receives', 'a', 'PWS', 'warning', 'message', 'from', 'a', 'network', 'with', 'a', 'particular', 'MCC', 'the', 'UE', 'can', 'translate']