def format_prefix
        values = CEF::PREFIX_ATTRIBUTES.keys.map { |k| self.send(k) }
        escaped = values.map do |value|
          escape_prefix_value(value)
        end
        escaped.join('|')
      end
def format_prefix
        values = CEF::PREFIX_ATTRIBUTES.keys.map { |k| self.send(k) }
        escaped = values.map do |value|
          escape_prefix_value(value)
        end
        escaped.join('|')
      end
returns a pipe-delimeted list of prefix attributes