Leave Protocol Sample Clauses

Leave Protocol. ^ Such as Join protocol, we start with n members and assume that member Md leaves the group. The sponsor in this case is the rightmost leaf node of the subtree rooted at leaving member’s sibling node. First, if the number of leaving member’s sibling node is two, each member updates its key tree by deleting the leaf node corresponding to Md. Then the former sibling of Md is updated to replace Md’s parent node. Otherwise each member only deleting the leaf node corresponding to Md. The sponsor generates a new key share, computes all [key, bkey] pairs on the key-path up to the root, and broadcasts the new set of bkey. This allows all members to compute the new group key. In Fig. 3, if member M7 leaves the group, every remaining member deletes < 1, 2 > and < 2, 6 >. After updating the tree, the sponsor (M10) picks a new share K<2,8>, recomputes ▇<▇,▇>, ▇<▇,▇>, ▇▇<▇,▇> and BK<1,2>, and broadcasts the updated tree T10 with BK1∗0. Upon receiving the broadcast message, all members compute the group key. Note that M7 cannot compute the group key, though he knows all the bkeys, because his share is no longer a part of the group key.

Leave Protocol. Employees will obtain testing following the most current DOH recommendations in such situations and will share the results with the District immediately upon receipt. The District has a right to investigate suspected misuse of this leave.

Leave Protocol. Once again, we start with members and assume that member leaves the group. The sponsor in this case is the rightmost leaf node of the subtree rooted at the leaving member’s sibling node. First off, as shown in Figure 4, each member updates its key tree by deleting the leaf node corresponding to . The former sibling of is promoted to replace ’s parent node. The sponsor generates a new key share, computes all pairs on the key-path up to the root, and broadcasts the new set of bkeys. This allows all members to compute the new group key. , and broadcasts the updated tree with . Upon receiving the broadcast message, all members compute the group key. Note that cannot compute the group key, though it knows all the bkeys, because its share is no longer part of the group key. One round and one message are required to complete a leave protocol. The number of modular exponentiation depends on the location of the leaving member and tree structure. Its upper bound is if all pairs on the key-path of the deepest node need to be recomputed. When either left or right subtree has single node and it is the sponsor (i.e. for example, its sibling leaves the group), 3 modular exponentiations are required (two by the sponsor and one by all other members).

Leave Protocol. Assume that a member ML wishes to leave a n-member group. First ML initiates the leave protocol by sending a leave request. When the other group members receive the request, they independently determine the sponsor node, which is defined as in [1] to be the right-most leaf node of the subtree rooted at the leaving member’s sibling node. The leave protocol works as shown in Algorithm 2. Algorithm 2 Leave Protocol in AFTD

Leave Protocol. Step 1: Each sponsor Msi in Tsi for i ∈ [1, k] • broadcasts tree BT(si ⟩ BT⟨s ⟩ k Msi i −→ ∪i=1 Ci Step 2: Each member • updates key tree by merging all trees, • removes all keys and bkeys from the sponsor node, The sponsor Ms (additionally) • generates new share rs and computes brs, • computes all keys and bkeys from its parent to the node just below root, • broadcasts updated tree BT(s⟩ k BT⟨s⟩ M ∪i=1 Ci ← − s Step 3: Each member computes group key using BT(s⟩ c.

Leave Protocol. The leave protocol is relatively simple. Assume that it has a group of n members and member Ml leaves the group. The rightmost leaf node of Ml’s sibling subtree is selected as the sponsor. After notification from system about the leave event, each remaining member updates its key tree by deleting Ml. The former sibling of Md is promoted to replace Md’s parent node. The sponsor must additionally refresh keys in its key-path. The process of leave protocol is illustrated as follows: 1) Each member removes the leaving member and relevant parent node, removes all keys and blinded keys pairs from sponsor to root node. The Sponsor Ms additionally, updates its share, computes then all keys and blinded keys in its key-path, and broadcasts updated key tree including all blinded keys. 2) Every member computes the group key using new key tree.

Leave Protocol. The leave protocol in CLIQUES is relatively simple. It needs only one round. Let Mc be group controller, and Ml be the member which leaves the group. First, Mc updates its secret Sc. Mc constructs then a broadcast message by embedding its new secret. Finally Mc broadcasts the message to the group. After running leave protocol, all remaining members compute the new group key. Although the contribution Sl is still factored into the new group key, the left member ▇▇ is unable ScS1S2∙∙∙Sn to compute the new group key, due to the absence of the subkey g Sl .

Leave Protocol. Authenticated key tree that M3 receives from director, M2

Leave Protocol. The main security requirement of member leaving is the secrecy of the subsequent (future) group key with respect to both outsiders and former group members. 1) When Mj wants to leave the group, intimates the GC and then GC, Ml generates a random number Rjj . Klj 2) Ml sends ΣRj x−1 Σ P by encrypting with xK to the corresponding group member Mi, i = j, (i.e) except leaving member. However, it is often times necessary to either to add a Klj EK ΣRt x−1 ΣP new member (or) delete an existing group member of the initial group creation. Naturally, it is desirable to do so without executing entire protocol a new. To address this issue we extend CGKA to DCGKA by proposing join pro-