Automated Fast-Track Reconfiguration of Group Communication Systems

ion level of program transformations from programming language expressions to reasoning about modules. It also improves the performance of the reconfiguration process, which requires only a few steps for each protocol layer passed by an event and thus scales up very well. Finally system updates can be handled much easier: the modification of a layer’s code only requires reproving the reconfiguration theorems for this particular layer while the reconfiguration of the protocol stack will remain unaffected or is re-executed automatically. Example 2. To reconfigure the stack Pt2pt ||| Mnak ||| Bottom for outgoing send-messages, CreateReconfiguredStack consults the following reconfiguration theorems. THM Pt2ptReconfDnMESend verif RECONFIGURING LAYER Pt2pt FOR EVENT DnM(ev, hdr) AND STATE s pt2pt ASSUMING getType ev = ESend ∧ getPeer ev 6= ls.rank YIELDS EVENTS [:DnM(ev, Full(Data(Iq.hi s pt2pt.sends.(getPeer ev)), hdr)):] AND STATE s pt2pt[.sends.(getPeer ev) ← Iq.add s pt2pt.sends.(getPeer ev) (getIov ev) hdr] THM MnakReconfDnMESend verif RECONFIGURING LAYER Mnak FOR EVENT DnM(ev, hdr) AND STATE s mnak ASSUMING getType ev = ESend YIELDS EVENTS [:DnM(ev, Full(NoHdr, hdr)):]