An X.509 certificate might come in many different formats, two of the most prominent being DER, a binary form, and PEM, an ASCII-encoded form. As the Avaya SBC currently only accepts PEM-encoded certificates, any binary DER certificates must be converted to PEM encoding. To convert a binary DER certificate into an ASCII-encoded PEM certificate, you must use a third party SSL library. The EMS ships with an open source SSL library called OpenSSL, which can be used to encode a DER certificate to PEM format.