Two-layer multi-strand cord comprising: - an internal layer of the cord made up of K=1 internal strand (Tl) having two layers (C1, C3) comprising: - an internal layer made up of Q=2, 3 or 4 internal metallic threads, and - an external layer made up of N external metallic threads of diameter d3 wound around the internal layer, - an external layer of the cord made up of L>1 external strands having two layers (C1', C3') wound around the internal layer of the cord, comprising: - an internal layer (C1') made up of Q'=2, 3 or 4 internal metallic threads (F1'), and - an external layer (C3') made up of N' external metallic threads (F3') of diameter d3' wound around the internal layer (C1'), characterized in that the cord has an energy-to-break per unit area ES ≥ 155 N.mm -1 with ES = ∑ i = 1 Nc F mi × ∑ i = 1 Nc A ti / Nc × Cfrag / D where: - ∑ i = 1 Nc F mi is the sum of the forces at break for the Nc threads, in Newtons; - Nc = Q+N+L x(Q'+N') is the total number of metallic threads; - D is the diameter of the cord, in mm; - ∑ i = 1 Nc A ti is the sum of the total elongation of the Nc threads, and is dimensionless; - Cfrag is the dimensionless coefficient of weakening of the cord, with C frag = 1 − sin ∝ f d 3 × d 3 ′ × ∑ i = 1 Q ′ + N ′ F mi × sin αt N × Cste where: d3 and d3' are expressed in mm, of is the angle of contact between the external metallic threads of the internal strand (Tl) and the external metallic threads (F3') of the external strands, expressed in radians, αt is the helix angle of each external strand expressed in radians; Cste = 1500 N.mm -2. - an internal layer of the cord made up of K=1 internal strand (Tl) having two layers (C1, C3) comprising: - an internal layer made up of Q=2, 3 or 4 internal metallic threads, and - an external layer made up of N external metallic threads of diameter d3 wound around the internal layer, - an external layer of the cord made up of L>1 external strands having two layers (C1', C3') wound around the internal layer of the cord, comprising: - an internal layer (C1') made up of Q'=2, 3 or 4 internal metallic threads (F1'), and - an external layer (C3') made up of N' external metallic threads (F3') of diameter d3' wound around the internal layer (C1'), characterized in that the cord has an energy-to-break per unit area ES ≥ 155 N.mm -1 with ES = ∑ i = 1 Nc F mi × ∑ i = 1 Nc A ti / Nc × Cfrag / D where: - ∑ i = 1 Nc F mi is the sum of the forces at break for the Nc threads, in Newtons; - Nc = Q+N+L x(Q'+N') is the total number of metallic threads; - D is the diameter of the cord, in mm; - ∑ i = 1 Nc A ti is the sum of the total elongation of the Nc threads, and is dimensionless; - Cfrag is the dimensionless coefficient of weakening of the cord, with C frag = 1 − sin ∝ f d 3 × d 3 ′ × ∑ i = 1 Q ′ + N ′ F mi × sin αt N × Cste where: d3 and d3' are expressed in mm, of is the angle of contact between the external metallic threads of the internal strand (Tl) and the external metallic threads (F3') of the external strands, expressed in radians, αt is the helix angle of each external strand expressed in radians; Cste = 1500 N.mm -2. - ∑ i = 1 Nc F mi is the sum of the forces at break for the Nc threads, in Newtons; - Nc = Q+N+L x(Q'+N') is the total number of metallic threads; - D is the diameter of the cord, in mm; - ∑ i = 1 Nc A ti is the sum of the total elongation of the Nc threads, and is dimensionless; - Cfrag is the dimensionless coefficient of weakening of the cord, with C frag = 1 − sin ∝ f d 3 × d 3 ′ × ∑ i = 1 Q ′ + N ′ F mi × sin αt N × Cste where: d3 and d3' are expressed in mm, of is the angle of contact between the external metallic threads of the internal strand (Tl) and the external metallic threads (F3') of the external strands, expressed in radians, αt is the helix angle of each external strand expressed in radians; Cste = 1500 N.mm -2. d3 and d3' are expressed in mm, of is the angle of contact between the external metallic threads of the internal strand (Tl) and the external metallic threads (F3') of the external strands, expressed in radians, αt is the helix angle of each external strand expressed in radians; Cste = 1500 N.mm -2.