Key Management Schemes for Multilayer and Multiple Simultaneous Secure Group Communication

Table 1

Comparison of storage and encryption cost.

	Dexter et al. scheme	Our scheme
Storage at KDC	(𝑡−1)(2𝑁−1)	2𝑁+𝑡−2
Storage at each user of layer 𝑖	(𝑡−1)(⌈log2𝑆𝑖⌉+𝑖)	𝑡+⌈log2𝑆𝑖⌉+𝑖−1
Number of elements encrypted during leave from layer 𝑖	(𝑡−1)(⌈log2𝑆𝑖⌉+𝑖)	⌈log2𝑆𝑖⌉+𝑖𝑡