diff --git a/Cargo.lock b/Cargo.lock
index 6184e55..4dd57f8 100644
--- a/Cargo.lock
+++ b/Cargo.lock
@@ -2,6 +2,24 @@
 # It is not intended for manual editing.
 version = 3
 
+[[package]]
+name = "autocfg"
+version = "0.1.7"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "1d49d90015b3c36167a20fe2810c5cd875ad504b39cff3d4eae7977e6b7c1cb2"
+
+[[package]]
+name = "autocfg"
+version = "1.0.1"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "cdb031dd78e28731d87d56cc8ffef4a8f36ca26c38fe2de700543e627f8a464a"
+
+[[package]]
+name = "base64ct"
+version = "1.1.1"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "e6b4d9b1225d28d360ec6a231d65af1fd99a2a095154c8040689617290569c5c"
+
 [[package]]
 name = "block-buffer"
 version = "0.7.3"
@@ -11,7 +29,7 @@ dependencies = [
  "block-padding",
  "byte-tools",
  "byteorder",
- "generic-array",
+ "generic-array 0.12.4",
 ]
 
 [[package]]
@@ -41,13 +59,49 @@ version = "1.0.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "baf1de4339761588bc0619e3cbc0120ee582ebb74b53b4efbf79117bd2da40fd"
 
+[[package]]
+name = "const-oid"
+version = "0.6.2"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "9d6f2aa4d0537bcc1c74df8755072bd31c1ef1a3a1b85a68e8404a8c353b7b8b"
+
+[[package]]
+name = "crypto-bigint"
+version = "0.2.11"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "f83bd3bb4314701c568e340cd8cf78c975aa0ca79e03d3f6d1677d5b0c9c0c03"
+dependencies = [
+ "generic-array 0.14.4",
+ "rand_core 0.6.3",
+ "subtle",
+]
+
+[[package]]
+name = "der"
+version = "0.4.4"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "28e98c534e9c8a0483aa01d6f6913bc063de254311bd267c9cf535e9b70e15b2"
+dependencies = [
+ "const-oid",
+ "crypto-bigint",
+]
+
 [[package]]
 name = "digest"
 version = "0.8.1"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "f3d0c8c8752312f9713efd397ff63acb9f85585afbf179282e720e7704954dd5"
 dependencies = [
- "generic-array",
+ "generic-array 0.12.4",
+]
+
+[[package]]
+name = "digest"
+version = "0.9.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "d3dd60d1080a57a05ab032377049e0591415d2b31afd7028356dbf3cc6dcb066"
+dependencies = [
+ "generic-array 0.14.4",
 ]
 
 [[package]]
@@ -65,6 +119,16 @@ dependencies = [
  "typenum",
 ]
 
+[[package]]
+name = "generic-array"
+version = "0.14.4"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "501466ecc8a30d1d3b7fc9229b122b2ce8ed6e9d9223f1138d4babb253e51817"
+dependencies = [
+ "typenum",
+ "version_check",
+]
+
 [[package]]
 name = "getrandom"
 version = "0.1.16"
@@ -93,22 +157,121 @@ version = "0.1.0"
 dependencies = [
  "rand",
  "rand_os",
+ "rsa",
  "serde",
  "sha2",
 ]
 
+[[package]]
+name = "lazy_static"
+version = "1.4.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "e2abad23fbc42b3700f2f279844dc832adb2b2eb069b2df918f455c4e18cc646"
+dependencies = [
+ "spin",
+]
+
 [[package]]
 name = "libc"
 version = "0.2.107"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "fbe5e23404da5b4f555ef85ebed98fb4083e55a00c317800bc2a50ede9f3d219"
 
+[[package]]
+name = "libm"
+version = "0.2.1"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "c7d73b3f436185384286bd8098d17ec07c9a7d2388a6599f824d8502b529702a"
+
+[[package]]
+name = "num-bigint-dig"
+version = "0.7.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "4547ee5541c18742396ae2c895d0717d0f886d8823b8399cdaf7b07d63ad0480"
+dependencies = [
+ "autocfg 0.1.7",
+ "byteorder",
+ "lazy_static",
+ "libm",
+ "num-integer",
+ "num-iter",
+ "num-traits",
+ "rand",
+ "serde",
+ "smallvec",
+ "zeroize",
+]
+
+[[package]]
+name = "num-integer"
+version = "0.1.44"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "d2cc698a63b549a70bc047073d2949cce27cd1c7b0a4a862d08a8031bc2801db"
+dependencies = [
+ "autocfg 1.0.1",
+ "num-traits",
+]
+
+[[package]]
+name = "num-iter"
+version = "0.1.42"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "b2021c8337a54d21aca0d59a92577a029af9431cb59b909b03252b9c164fad59"
+dependencies = [
+ "autocfg 1.0.1",
+ "num-integer",
+ "num-traits",
+]
+
+[[package]]
+name = "num-traits"
+version = "0.2.14"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "9a64b1ec5cda2586e284722486d802acf1f7dbdc623e2bfc57e65ca1cd099290"
+dependencies = [
+ "autocfg 1.0.1",
+ "libm",
+]
+
 [[package]]
 name = "opaque-debug"
 version = "0.2.3"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "2839e79665f131bdb5782e51f2c6c9599c133c6098982a54c794358bf432529c"
 
+[[package]]
+name = "pem-rfc7468"
+version = "0.2.4"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "84e93a3b1cc0510b03020f33f21e62acdde3dcaef432edc95bea377fbd4c2cd4"
+dependencies = [
+ "base64ct",
+]
+
+[[package]]
+name = "pkcs1"
+version = "0.2.4"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "116bee8279d783c0cf370efa1a94632f2108e5ef0bb32df31f051647810a4e2c"
+dependencies = [
+ "der",
+ "pem-rfc7468",
+ "zeroize",
+]
+
+[[package]]
+name = "pkcs8"
+version = "0.7.6"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "ee3ef9b64d26bad0536099c816c6734379e45bbd5f14798def6809e5cc350447"
+dependencies = [
+ "der",
+ "pem-rfc7468",
+ "pkcs1",
+ "spki",
+ "zeroize",
+]
+
 [[package]]
 name = "ppv-lite86"
 version = "0.2.15"
@@ -192,6 +355,27 @@ dependencies = [
  "rand_core 0.5.1",
 ]
 
+[[package]]
+name = "rsa"
+version = "0.5.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "e05c2603e2823634ab331437001b411b9ed11660fbc4066f3908c84a9439260d"
+dependencies = [
+ "byteorder",
+ "digest 0.9.0",
+ "lazy_static",
+ "num-bigint-dig",
+ "num-integer",
+ "num-iter",
+ "num-traits",
+ "pkcs1",
+ "pkcs8",
+ "rand",
+ "serde",
+ "subtle",
+ "zeroize",
+]
+
 [[package]]
 name = "serde"
 version = "1.0.130"
@@ -219,11 +403,38 @@ source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "a256f46ea78a0c0d9ff00077504903ac881a1dafdc20da66545699e7776b3e69"
 dependencies = [
  "block-buffer",
- "digest",
+ "digest 0.8.1",
  "fake-simd",
  "opaque-debug",
 ]
 
+[[package]]
+name = "smallvec"
+version = "1.7.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "1ecab6c735a6bb4139c0caafd0cc3635748bbb3acf4550e8138122099251f309"
+
+[[package]]
+name = "spin"
+version = "0.5.2"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "6e63cff320ae2c57904679ba7cb63280a3dc4613885beafb148ee7bf9aa9042d"
+
+[[package]]
+name = "spki"
+version = "0.4.1"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "5c01a0c15da1b0b0e1494112e7af814a678fec9bd157881b49beac661e9b6f32"
+dependencies = [
+ "der",
+]
+
+[[package]]
+name = "subtle"
+version = "2.4.1"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "6bdef32e8150c2a081110b42772ffe7d7c9032b606bc226c8260fd97e0976601"
+
 [[package]]
 name = "syn"
 version = "1.0.81"
@@ -235,6 +446,18 @@ dependencies = [
  "unicode-xid",
 ]
 
+[[package]]
+name = "synstructure"
+version = "0.12.6"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "f36bdaa60a83aca3921b5259d5400cbf5e90fc51931376a9bd4a0eb79aa7210f"
+dependencies = [
+ "proc-macro2",
+ "quote",
+ "syn",
+ "unicode-xid",
+]
+
 [[package]]
 name = "typenum"
 version = "1.14.0"
@@ -247,6 +470,12 @@ version = "0.2.2"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "8ccb82d61f80a663efe1f787a51b16b5a51e3314d6ac365b08639f52387b33f3"
 
+[[package]]
+name = "version_check"
+version = "0.9.3"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "5fecdca9a5291cc2b8dcf7dc02453fee791a280f3743cb0905f8822ae463b3fe"
+
 [[package]]
 name = "wasi"
 version = "0.9.0+wasi-snapshot-preview1"
@@ -258,3 +487,24 @@ name = "wasi"
 version = "0.10.2+wasi-snapshot-preview1"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "fd6fbd9a79829dd1ad0cc20627bf1ed606756a7f77edff7b66b7064f9cb327c6"
+
+[[package]]
+name = "zeroize"
+version = "1.4.3"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "d68d9dcec5f9b43a30d38c49f91dfedfaac384cb8f085faca366c26207dd1619"
+dependencies = [
+ "zeroize_derive",
+]
+
+[[package]]
+name = "zeroize_derive"
+version = "1.2.2"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "65f1a51723ec88c66d5d1fe80c841f17f63587d6691901d66be9bec6c3b51f73"
+dependencies = [
+ "proc-macro2",
+ "quote",
+ "syn",
+ "synstructure",
+]
diff --git a/Cargo.toml b/Cargo.toml
index 9b8cb9d..960c91b 100644
--- a/Cargo.toml
+++ b/Cargo.toml
@@ -15,4 +15,8 @@ rand_os = "*"
 # ed25519-dalek = { version = "1.0", features = ["serde"] }
 sha2 = "0.8.1"
 rand = "*"
+rsa = { version = "0.5", features = ["serde"] }
 serde = { version = "1.0", features = ["derive", "alloc"], default-features = false }
+
+[profile.dev.package.num-bigint-dig]
+opt-level = 3
diff --git a/src/crypto.rs b/src/crypto.rs
index cff1a90..030f880 100644
--- a/src/crypto.rs
+++ b/src/crypto.rs
@@ -1,49 +1,67 @@
+/// This module has wrappers for cryptography with RSA algorithms.
+/// Its main structs - `PublicKey` and `Keys` implement all functions for key generation, signatures and asymmetric encryption
 use alloc::vec::Vec;
+use alloc::vec;
 use serde::{Deserialize, Serialize};
+use rsa::{RsaPublicKey, RsaPrivateKey, PaddingScheme, PublicKey as RPK};
+use rsa::errors::Result as RsaRes;
+use rand::rngs::OsRng;
+
+static KEY_LENGTH: usize = 2048;
+
 
 /// Public key of a node
 #[derive(Debug, PartialEq, Serialize, Deserialize, Clone)]
 pub struct PublicKey {
-    pub key: [u8; 32],
+    pub key: RsaPublicKey,
 }
 
 impl PublicKey {
-    /// Check if the sign is valid for gived data and key
-    pub fn verify_sign(&self, _data: &[u8], _sign: &[u8]) -> bool {
-        todo!()
+    /// Check if the sign is valid for given data and key
+    pub fn verify_sign(&self, data: &[u8], sign: &[u8]) -> bool {
+        self.key.verify(PaddingScheme::PKCS1v15Sign { hash: None }, data, sign).is_ok()
     }
 
     /// Encrypt some data for a user with this public key
-    pub fn encrypt_data(&self, _data: &[u8]) -> Vec<u8> {
-        todo!()
+    pub fn encrypt_data(&self, data: &[u8]) -> RsaRes<Vec<u8>> {
+        self.key.encrypt(&mut OsRng {}, PaddingScheme::PKCS1v15Encrypt, data)
     }
 }
 
 /// Key pair (public and secret) for a node, should be stored locally
 #[derive(Debug, Serialize, Deserialize, Clone)]
-pub struct Keys {}
+pub struct Keys {
+    public_key: RsaPublicKey,
+    private_key: RsaPrivateKey,
+}
 
 impl Keys {
     /// Generate new random key
-    pub fn generate() -> Keys {
-        todo!()
+    pub fn generate() -> Self {
+        let mut rng = OsRng;
+        let private_key = RsaPrivateKey::new(&mut rng, KEY_LENGTH).expect("failed to generate a key");
+        let public_key = RsaPublicKey::from(&private_key);
+        Self {
+            private_key,
+            public_key,
+        }
     }
 }
 
 impl Keys {
     /// Sign content using these keys
-    pub fn sign(&self, _content: &[u8]) -> Vec<u8> {
-        todo!()
+    pub fn sign(&self, content: &[u8]) -> RsaRes<Vec<u8>> {
+        self.private_key.sign(PaddingScheme::PKCS1v15Sign { hash: None }, content)
     }
 
     /// Decrypt data
-    pub fn decrypt_data(&self, _data_encrypted: &[u8]) -> Option<Vec<u8>> {
-        todo!()
+    pub fn decrypt_data(&self, data_encrypted: &[u8]) -> RsaRes<Vec<u8>> {
+        self.private_key.decrypt(PaddingScheme::PKCS1v15Encrypt, data_encrypted)
     }
 
     /// Get public key
     pub fn get_public(&self) -> PublicKey {
-        todo!()
+        PublicKey { key: self.public_key.clone() }
     }
 }
 
@@ -52,8 +70,8 @@ fn test_encrypt() {
     let data = vec![0, 5, 8, 135, 67];
     let keys = Keys::generate();
     assert_eq!(
-        keys.decrypt_data(keys.get_public().encrypt_data(data)),
-        Some(data)
+        keys.decrypt_data(&keys.get_public().encrypt_data(&data).unwrap()).unwrap(),
+        data
     );
 }
 
@@ -62,14 +80,14 @@ fn test_invalid_encrypt() {
     let data = vec![0, 5, 8, 135, 67];
     let keys_1 = Keys::generate();
     let keys_2 = Keys::generate();
-    assert!(keys_2.decrypt_data(keys_1.get_public().encrypt_data(data)) != Some(data));
+    assert!(keys_2.decrypt_data(&keys_1.get_public().encrypt_data(&data).unwrap()).is_err());
 }
 
 #[test]
 fn test_signing() {
     let data = vec![0, 5, 8, 135, 67];
     let keys = Keys::generate();
-    assert!(keys.get_public().verify_sign(data, keys.sign(data)));
+    assert!(keys.get_public().verify_sign(&data, &keys.sign(&data).unwrap()));
 }
 
 #[test]
@@ -77,5 +95,5 @@ fn test_invalid_signing() {
     let data = vec![0, 5, 8, 135, 67];
     let keys_1 = Keys::generate();
     let keys_2 = Keys::generate();
-    assert!(keys_2.get_public().verify_sign(data, keys_1.sign(data)));
+    assert!(!keys_2.get_public().verify_sign(&data, &keys_1.sign(&data).unwrap()));
 }
diff --git a/src/interface.rs b/src/interface.rs
new file mode 100644
index 0000000..e1bee76
--- /dev/null
+++ b/src/interface.rs
@@ -0,0 +1 @@
+pub trait Interface {}
diff --git a/src/ironforce.rs b/src/ironforce.rs
new file mode 100644
index 0000000..2f7ed9c
--- /dev/null
+++ b/src/ironforce.rs
@@ -0,0 +1,3 @@
+pub struct IronForce {
+
+}
diff --git a/src/lib.rs b/src/lib.rs
index e332a88..ff8301e 100644
--- a/src/lib.rs
+++ b/src/lib.rs
@@ -3,8 +3,13 @@
 
 extern crate alloc;
 extern crate rand;
+extern crate rsa;
 
 mod crypto;
+mod ironforce;
+mod message;
+mod transport;
+mod interface;
 
 #[cfg(test)]
 mod tests {
diff --git a/src/message.rs b/src/message.rs
new file mode 100644
index 0000000..e69de29
diff --git a/src/transport.rs b/src/transport.rs
new file mode 100644
index 0000000..8b13789
--- /dev/null
+++ b/src/transport.rs
@@ -0,0 +1 @@
+