OPC Unified Architecture – Part 12: Discovery and Global Services
7.8.4.8 RsaMinApplicationCertificateType
This type is used to describe Certificates intended for use as an ApplicationInstanceCertificate. They shall have an RSA key size of 1024 or 2048 bits. All Applications which support the Basic128Rsa15 and Basic256 profiles (see OPC 10000-7) shall have a Certificate of this type. This type is defined in Table 53.