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All communication between pillars/clients and the coordinating layer may be encrypted using SSL. The certificates used in the communication between pillars/clients and coordinating layer are issued by the coordinating bodymust be trusted by the participants, and a mechanism for distributing (public) certificates is needed. A recipe for setting up Activemq pki can be found at http://activemq.apache.org/how-do-i-use-ssl.html
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To ensure the authenticity of exchanged messages, they may be signed and optionally encrypted for confidentiality. Data transfers may be encrypted as well, using HTTPS. The certificates used for signing og encrypting data and messages are issued by the SLA owners parties involved. - possibly assisted by the coordinating body.
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