The paper presents hierarchical identity-based encryption (HIDE) and signature (HIDS) schemes that are secure against total collusion and chosen ciphertext attacks in the random oracle model. The schemes are based on the difficulty of the Bilinear Diffie-Hellman (BDH) problem and use elliptic curves or abelian varieties. The authors introduce a new construction that extends the Boneh-Franklin identity-based encryption scheme, making it fully scalable and efficient. The ciphertext length and decryption complexity grow linearly with the depth of the recipient in the hierarchy. The paper also discusses a dual-identity-based encryption (Dual-HIDE) scheme, which reduces ciphertext expansion when the sender and recipient are close in the hierarchy. Additionally, the authors propose methods to restrict key escrow and authenticated key agreement protocols to enhance security. The security of the schemes is proven based on the hardness of the BDH problem, and the paper includes concrete examples and extensions.The paper presents hierarchical identity-based encryption (HIDE) and signature (HIDS) schemes that are secure against total collusion and chosen ciphertext attacks in the random oracle model. The schemes are based on the difficulty of the Bilinear Diffie-Hellman (BDH) problem and use elliptic curves or abelian varieties. The authors introduce a new construction that extends the Boneh-Franklin identity-based encryption scheme, making it fully scalable and efficient. The ciphertext length and decryption complexity grow linearly with the depth of the recipient in the hierarchy. The paper also discusses a dual-identity-based encryption (Dual-HIDE) scheme, which reduces ciphertext expansion when the sender and recipient are close in the hierarchy. Additionally, the authors propose methods to restrict key escrow and authenticated key agreement protocols to enhance security. The security of the schemes is proven based on the hardness of the BDH problem, and the paper includes concrete examples and extensions.