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seCurity and PrivaCy in smart Grids
on the handling of CRLs (Certificate Revocation Lists), online vali-
dation of certificates (e.g., using the OCSP, Online Certificate Status
Protocol) is not currently considered in edition 1 as communication
links are severely limited in substations. Another characteristic of
energy automation communication are long-lived connections. is
requires the definition of strict key update and CRL update inter-
vals to restrict the application of cryptographic keys not only for a
dedicated number of packets but also for a dedicated time. Another
challenge to consider is the interoperability requirements between the
implementations of the products of different vendors. Nevertheless,
TLS as underlying security prot