Abstract: The invention concerns a method for preauthentication of a first entity (10) by a second entity (1) communicating with each other through a wireless link, including the following steps: the second entity (1) emits (23?) a challenge value (c); if the first entity (10) receives (23) a challenge value (c?) it applies to the received challenge value a predefined transformation (g) known to the second entity, to obtain a first transformed value (r), then emits (24) the first transformed value obtained; and if the second entity receives (24?) a transformed value (r?) it compares (25?) the received transformed value to a second transformed value (r?) obtained by applying the predefined transformation (g) to the emitted challenge value, and estimates the preauthentication to be successful if the result of the comparison between the second transformed value obtained and the received transformed value is less than a predefined threshold (m).

Abstract: A flanged prosthesis (10) comprises a tubular body (18) equipped at one end with an external flange (19) designed for the anastomosis of the prosthesis to a tubular duct equipped with an opening. The flange (19) is made of a textile material and comprises at least one seam (324, 360, 362) shaping it at the end of the tubular body (18).

Abstract: The invention relates to a vascular prosthesis capable of being anastomosed onto a tubular pipe with a side opening or an end opening. The prothesis having, at at least one of its ends, an annular sheet delimited by a free edge designed to be positioned in the immediate vicinity of opening in the pipe. The sheet is shaped so that it can be applied around the opening in the pipe against the inside or outside wall of the latter, while preserving its free edge in the immediate vicinity of the periphery of the opening in the pipe.