We propose two symmetric-key management schemes for the encryption of scalable compressed video content. The schemes are applicable to MPEG-4 Fine Grain Scalability video coding. Our constructions make use of only hash functions and achieve the optimal bound regarding the minimum number of keys and the time complexity in computing all the decryption keys. We also formalize new security notions about collusion-resistance. Unlike prior key management schemes, our second scheme resists to certain collusion attacks. The collusionresistance achieved is practical and hence sufficient for encryption of scalable video streams.