diff --git a/crypt_algo.hpp b/crypt_algo.hpp
new file mode 100644
index 0000000..deabf53
--- /dev/null
+++ b/crypt_algo.hpp
@@ -0,0 +1,92 @@
+#pragma once
+
+#include <openssl/sha.h>
+#include <array>
+#include <vector>
+
+namespace cipher
+{
+
+namespace crypt
+{
+
+using buffer = std::vector<uint8_t>;
+using key = std::array<uint8_t, SHA_DIGEST_LENGTH>;
+
+/**
+ * @enum Confidentiality Algorithms
+ *
+ * The Confidentiality Algorithm Number specifies the encryption/decryption
+ * algorithm field that is used for encrypted payload data under the session.
+ * The ‘encrypted’ bit in the payload type field being set identifies packets
+ * with payloads that include data that is encrypted per this specification.
+ * When payload data is encrypted, there may be additional “Confidentiality
+ * Header” and/or “Confidentiality Trailer” fields that are included within the
+ * payload. The size and definition of those fields is specific to the
+ * particular confidentiality algorithm.
+ */
+enum class Algorithms : uint8_t
+{
+    NONE,               /**< No encryption (mandatory option) */
+    AES_CBC_128,        /**< AES-CBC-128 Algorithm (mandatory option) */
+    xRC4_128,           /**< xRC4-128 Algorithm (optional option) */
+    xRC4_40,            /**< xRC4-40 Algorithm (optional option) */
+};
+
+/**
+ * @class Interface
+ *
+ * Interface is the base class for the Confidentiality Algorithms.
+ */
+class Interface
+{
+    public:
+        /**
+         * @brief Constructor for Interface
+         *
+         * @param[in] - Session Integrity key to generate K2
+         * @param[in] - Additional keying material to generate K2
+         */
+        explicit Interface(const buffer& sik, const key& addKey);
+
+        Interface() = delete;
+        virtual ~Interface() = default;
+        Interface(const Interface&) = default;
+        Interface& operator=(const Interface&) = default;
+        Interface(Interface&&) = default;
+        Interface& operator=(Interface&&) = default;
+
+        /**
+         * @brief Decrypt the incoming payload
+         *
+         * @param[in] packet - Incoming IPMI packet
+         * @param[in] sessHeaderLen - Length of the IPMI Session Header
+         * @param[in] payloadLen - Length of the encrypted IPMI payload
+         *
+         * @return decrypted payload if the operation is successful
+         */
+        virtual buffer decryptPayload(
+                const buffer& packet,
+                const size_t sessHeaderLen,
+                const size_t payloadLen) const = 0;
+
+        /**
+         * @brief Encrypt the outgoing payload
+         *
+         * @param[in] payload - plain payload for the outgoing IPMI packet
+         *
+         * @return encrypted payload if the operation is successful
+         *
+         */
+        virtual buffer encryptPayload(buffer& payload) const = 0;
+
+    protected:
+
+        /** @brief K2 is the key used for encrypting data */
+        key k2;
+};
+
+}// namespace crypt
+
+}// namespace cipher
+