381 bit affine x coordinate, encoded into 48 big-endian bytes. Since we have 3 bits left over in the beginning, the first bit is set to 1 iff y coordinate is the lexicographically largest of the two valid ys. The public key fingerprint is the first 4 bytes of hash256(serialize(pubkey)).
signature (96 bytes)
Two 381 bit integers (affine x coordinate), encoded into two 48 big-endian byte arrays. Since we have 3 bits left over in the beginning, the first bit is set to 1 iff the y coordinate is the lexicographically largest of the two valid ys. (The term with the i is compared first, i.e 3i + 1 > 2i + 7). The second bit is set to 1 iff the signature was generated using the prepend method, and should be verified using the prepend method.
The most-significant three bits of a G1 or G2 encoding should be masked away before the coordinate(s) are interpreted. These bits are used to unambiguously represent the underlying element:
The most significant bit, when set, indicates that the point is in compressed form. Otherwise, the point is in uncompressed form.
The second-most significant bit indicates that the point is at infinity. If this bit is set, the remaining bits of the group element's encoding should be set to zero.
The third-most significant bit is set if (and only if) this point is in compressed form and it is not the point at infinity and its y-coordinate is the lexicographically largest of the two associated with the encoded x-coordinate.
chia network
private key (32 bytes)
Big endian integer.
pubkey (48 bytes)
381 bit affine x coordinate, encoded into 48 big-endian bytes. Since we have 3 bits left over in the beginning, the first bit is set to 1 iff y coordinate is the lexicographically largest of the two valid ys. The public key fingerprint is the first 4 bytes of hash256(serialize(pubkey)).
signature (96 bytes)
Two 381 bit integers (affine x coordinate), encoded into two 48 big-endian byte arrays. Since we have 3 bits left over in the beginning, the first bit is set to 1 iff the y coordinate is the lexicographically largest of the two valid ys. (The term with the i is compared first, i.e 3i + 1 > 2i + 7). The second bit is set to 1 iff the signature was generated using the prepend method, and should be verified using the prepend method.
eth2.0
(TBD）
zkcrypto
The most-significant three bits of a G1 or G2 encoding should be masked away before the coordinate(s) are interpreted. These bits are used to unambiguously represent the underlying element:
The most significant bit, when set, indicates that the point is in compressed form. Otherwise, the point is in uncompressed form. The second-most significant bit indicates that the point is at infinity. If this bit is set, the remaining bits of the group element's encoding should be set to zero. The third-most significant bit is set if (and only if) this point is in compressed form and it is not the point at infinity and its y-coordinate is the lexicographically largest of the two associated with the encoded x-coordinate.