An electronic key pre-distribution device for configuring multiple network nodes (210, 211) with local key information, the key pre-distribution device comprising - a storage comprising information representing a first secret isogeny ( φ; s) for a first elliptic curve (131; E 1) and a second secret isogeny ( φ'; s) for a second elliptic curve (132; E 2), an isogeny being arranged to receive a point on an elliptic curve and to produce a point on an elliptic curve as output, - a processor circuit configured to - obtain a digital identifier for a network node, - apply at least a first hash function and a second hash function to the digital identifier, the first and second hash functions mapping the digital identifier to a first public point (141; H 1) and a second public point (142; H 2) on a first elliptic curve and second elliptic curve, the first elliptic curve being different from the second elliptic curve, the first and second public point being part of public key material for the network node, - apply the first and second secret isogeny to the first and second public elliptic curve point (141, 142), thus obtaining a first private elliptic curve point and second private elliptic curve point being part of private key material for the network node, and - a communication interface arranged to configure the network node with the first and second private elliptic curve point. - a storage comprising information representing a first secret isogeny ( φ; s) for a first elliptic curve (131; E 1) and a second secret isogeny ( φ'; s) for a second elliptic curve (132; E 2), an isogeny being arranged to receive a point on an elliptic curve and to produce a point on an elliptic curve as output, - a processor circuit configured to - obtain a digital identifier for a network node, - apply at least a first hash function and a second hash function to the digital identifier, the first and second hash functions mapping the digital identifier to a first public point (141; H 1) and a second public point (142; H 2) on a first elliptic curve and second elliptic curve, the first elliptic curve being different from the second elliptic curve, the first and second public point being part of public key material for the network node, - apply the first and second secret isogeny to the first and second public elliptic curve point (141, 142), thus obtaining a first private elliptic curve point and second private elliptic curve point being part of private key material for the network node, and - obtain a digital identifier for a network node, - apply at least a first hash function and a second hash function to the digital identifier, the first and second hash functions mapping the digital identifier to a first public point (141; H 1) and a second public point (142; H 2) on a first elliptic curve and second elliptic curve, the first elliptic curve being different from the second elliptic curve, the first and second public point being part of public key material for the network node, - apply the first and second secret isogeny to the first and second public elliptic curve point (141, 142), thus obtaining a first private elliptic curve point and second private elliptic curve point being part of private key material for the network node, and - a communication interface arranged to configure the network node with the first and second private elliptic curve point.