Agreement Phase. Initialize lock := ∞, m := mP and k := 0. Repeat the following loop – At time (12k + 16) · ∆: Initiate ΠGBA on input m. – At time (12k + 20) · ∆: • Let (v, g) be the output of P . If lock = ∞ then: ∗ If g = 2, set lock := 1. ∗ If g = 1, then set m := v. ∗ If g = 0, then set m = ⊥. – At time (12k + 24) · ∆: • Initiate ΠGBA on input m. • Let (v, g) be the output of P . If lock = ∞ then: ∗ If g = 1, then set m := v. – At time (12k + 27) · ∆: • Multicast m. ∗ If g = 0, then set m = ⊥. • Set k := k + 1 and denote mj the message received from Pj . Let ℓ denote the output obtained from ΠLeader. • If lock = 0, P outputs m and terminates. • If lock = ∞ and m = ⊥, then P sets m := mℓ. • If lock = 1, then P sets lock := 0.
Agreement Phase. After receiving an offer, supplier and customer may negotiate service properties and the pricing scheme. The parties agree on mutual commitments by the result of a (i) fixed price order, (ii) auction, (iii) tender, (vi) exchange, or (v) bilateral negotiation. Any pricing scheme is regarded as a type of price (e.g., metered-usage pricing).
Agreement Phase. After removing the faulty processors, each fault-free processor can achieve agreement by exchanging its value with one another again. Figure 4. IBA Protocol Figure 5(a). The transmission behavior of faulty processors. Figure 5(b). The ic-tree of processor Pe. Figure 5(c). The result of processor Pe.
Agreement Phase. Pi starts the agreement phase by broadcasting a нelp_req message (line 19) only if it has not previously acquired a certificate (due to the check at line 18). If Xx receives a нelp_req message in round 2 of the agreement phase (line 21), Pi replies via a нelp_reply message (line 22) which includes (1) an acquired certificate (if any), and (2) a partial signature of Pi ’s proposal to allow for a (potential) creation of a specific certificate. Pi executes the logic of rounds 3 and 4 only if it has not previously acquired a certificate (due to the checks at lines 24 and 34). In round 3, Pi aims to acquire a certificate: • If Pi receives a valid certificate in a нelp_reply message (line 25), Pi acquires the certificate (line 26). • Otherwise, Pi checks if it has received the same value from t+1 processes via нelp_reply messages (line 27). If so, Pi constructs a specific certificate by combining the received t + 1 partial signatures into a (t + 1)-combined threshold signature (line 29). • If neither of previous cases occurs, Pi aims to build a general certificate. To this end, Pi broadcasts a illow-iny message (line 32) which carries a partial signature of the “allow any” string. In round 4, Pi either receives a formed certificate from another process (line 35) or con- structs a general certificate (line 39). At the end of round 4, Xx proposes the acquired value- certificate pair to EBA (line 40). Finally, when Xx decides from EBA (line 41), it decides from stronc (line 42). Strong Byzantine Agreement with Adaptive Word Complexity Algorithm 1 stronc: Pseudocode (for process Pi) 1: Uses:
