Hi Teslum, I used same thing for my iOS application, what option need to select ? Thanks

Thank you Quinn, After generating public and private keys need to generate PEM format like, -----BEGIN PUBLIC KEY----- // base64String -----END PUBLIC KEY----- -----BEGIN PRIVATE KEY----- // base64String -----END PRIVATE KEY----- This is the java code for generating keys and convert pem format , required same for this: @Log@Servicepublic class ECCService { @Value("${forwardsecrecy.ecc.curve:Curve25519}") String curve; @Value("${forwardsecrecy.ecc.algorithm:EC}") String algorithm; @Value("${forwardsecrecy.ecc.keyDerivationAlgorithm:ECDH}") String keyDerivationAlgorithm; @Value("${forwardsecrecy.ecc.provider:BC}") String provider; @Value("${forwardsecrecy.ecc.keyExpiryHrs:24}") int keyExpiry; private KeyPair generateKey() throws NoSuchProviderException, NoSuchAlgorithmException, InvalidAlgorithmParameterException { KeyPairGenerator kpg; kpg = KeyPairGenerator.getInstance(algorithm, provider); X9ECParameters ecP = CustomNamedCurves.getByName(curve); ECParameterSpec ecSpec = EC5Util.convertToSpec(ecP); kpg.initialize(ecSpec); final KeyPair kp = kpg.genKeyPair(); log.info("Key pair generated " + kp.getPublic().getAlgorithm()); return kp; } public SerializedKeyPair getKeyPair() throws NoSuchProviderException, NoSuchAlgorithmException, InvalidAlgorithmParameterException { final KeyPair kp = this.generateKey(); final String privateKey = this.getPEMEncodedStream(kp.getPrivate(),true); final String publicKey = this.getPEMEncodedStream(kp.getPublic(), false); Date date = new Date(); Calendar cl = Calendar. getInstance(); cl.setTime(date); cl.add(Calendar.HOUR, keyExpiry); TimeZone tz = TimeZone.getTimeZone("UTC"); DateFormat df = new SimpleDateFormat("yyyy-MM-dd'T'HH:mm:ss.SSS'Z'"); // Quoted "Z" to indicate UTC, no timezone offset df.setTimeZone(tz); String expiryAsISO = df.format(cl.getTime()); final DHPublicKey dhPublicKey = new DHPublicKey(expiryAsISO,"",publicKey); final KeyMaterial keyMaterial = new KeyMaterial(keyDerivationAlgorithm,curve,"",dhPublicKey); final SerializedKeyPair serializedKeyPair = new SerializedKeyPair(privateKey, keyMaterial); return serializedKeyPair; } private String getPEMEncodedStream(final Key key, boolean privateKey) { final PKCS8EncodedKeySpec pkcs8KeySpec = new PKCS8EncodedKeySpec(key.getEncoded()); final StringBuilder sb = new StringBuilder(); final String keyType = privateKey ? "PRIVATE" : "PUBLIC"; sb.append("-----BEGIN " + keyType + " KEY-----"); sb.append(new String(Base64.getEncoder().encode(pkcs8KeySpec.getEncoded()))); sb.append("-----END " + keyType + " KEY-----"); return sb.toString(); } }