code: CipherBox newReadCipher() throws NoSuchAlgorithmException {
          BulkCipher cipher = cipherSuite.cipher;
          CipherBox box;
          if (isClient) {
              box = cipher.newCipher(protocolVersion, svrWriteKey, svrWriteIV,
                                     sslContext.getSecureRandom(), false);
              svrWriteKey = null;
              svrWriteIV = null;
          } else {
              box = cipher.newCipher(protocolVersion, clntWriteKey, clntWriteIV,
                                     sslContext.getSecureRandom(), false);
              clntWriteKey = null;
              clntWriteIV = null;
          }
          return box;
      }
docs: Create a new read cipher and return it to caller.