diff --git a/Cargo.lock b/Cargo.lock
index 03ecc657d..eea698b36 100644
--- a/Cargo.lock
+++ b/Cargo.lock
@@ -660,6 +660,20 @@ dependencies = [
  "vergen 3.0.4 (registry+https://github.com/rust-lang/crates.io-index)",
 ]
 
+[[package]]
+name = "darwinia-chainrelay"
+version = "0.1.0"
+dependencies = [
+ "darwinia-chainrelay-poa 0.1.0",
+ "sr-std 2.0.0 (git+https://github.com/paritytech/substrate.git)",
+ "srml-support 2.0.0 (git+https://github.com/paritytech/substrate.git)",
+ "srml-system 2.0.0 (git+https://github.com/paritytech/substrate.git)",
+]
+
+[[package]]
+name = "darwinia-chainrelay-poa"
+version = "0.1.0"
+
 [[package]]
 name = "darwinia-staking"
 version = "0.1.0"
diff --git a/Cargo.toml b/Cargo.toml
index adc22a05b..340f4c43d 100644
--- a/Cargo.toml
+++ b/Cargo.toml
@@ -70,6 +70,8 @@ members = [
     "srml/kton",
     "srml/support",
 	"srml/try",
+	"srml/chainrelay",
+	"srml/chainrelay/poa"
 ]
 
 exclude = ["node/runtime/wasm"]
diff --git a/node/cli/src/lib.rs b/node/cli/src/lib.rs
index 468333a5f..217b880b2 100644
--- a/node/cli/src/lib.rs
+++ b/node/cli/src/lib.rs
@@ -47,6 +47,7 @@ pub enum ChainSpec {
 	FlamingFir,
 	/// Whatever the current runtime is with the "global testnet" defaults.
 	StagingTestnet,
+	CrayfishTestnet,
 }
 
 /// Custom subcommands.
@@ -129,6 +130,7 @@ impl ChainSpec {
 			ChainSpec::Development => chain_spec::development_config(),
 			ChainSpec::LocalTestnet => chain_spec::local_testnet_config(),
 			ChainSpec::StagingTestnet => chain_spec::staging_testnet_config(),
+			ChainSpec::CrayfishTestnet => chain_spec::crayfish_testnet_config(),
 		})
 	}
 
@@ -136,8 +138,9 @@ impl ChainSpec {
 		match s {
 			"dev" => Some(ChainSpec::Development),
 			"local" => Some(ChainSpec::LocalTestnet),
-			"" | "fir" | "flaming-fir" => Some(ChainSpec::FlamingFir),
+			"fir" | "flaming-fir" => Some(ChainSpec::FlamingFir),
 			"staging" => Some(ChainSpec::StagingTestnet),
+			"" => Some(ChainSpec::CrayfishTestnet),
 			_ => None,
 		}
 	}
@@ -166,7 +169,12 @@ where
 			|exit, _cli_args, _custom_args, config: Config<_, _>| {
 				info!("{}", version.name);
 				info!("  version {}", config.full_version());
-				info!("  by Parity Technologies, 2017-2019");
+				info!("  _____                      _       _       ");
+				info!(" |  __ \\                   (_)     (_)      ");
+				info!(" | |  | | __ _ _ ____      ___ _ __  _  __ _ ");
+				info!(" | |  | |/ _` | '__\\ \\ /\\ / / | '_ \\| |/ _` |");
+				info!(" | |__| | (_| | |   \\ V  V /| | | | | | (_| |");
+				info!(" |_____/ \\__,_|_|    \\_/\\_/ |_|_| |_|_|\\__,_|");
 				info!("Chain specification: {}", config.chain_spec.name());
 				info!("Node name: {}", config.name);
 				info!("Roles: {:?}", config.roles);
diff --git a/node/runtime/src/lib.rs b/node/runtime/src/lib.rs
index f837c9a1a..27f8e1e81 100644
--- a/node/runtime/src/lib.rs
+++ b/node/runtime/src/lib.rs
@@ -264,7 +264,7 @@ parameter_types! {
 impl session::Trait for Runtime {
 	type OnSessionEnding = Staking;
 	type SessionHandler = SessionHandlers;
-	type ShouldEndSession = session::PeriodicSessions<Period, Offset>;
+	type ShouldEndSession = Babe;
 	type Event = Event;
 	type Keys = SessionKeys;
 	type ValidatorId = <Self as system::Trait>::AccountId;
diff --git a/srml/chainrelay/Cargo.toml b/srml/chainrelay/Cargo.toml
new file mode 100644
index 000000000..c42d9bb81
--- /dev/null
+++ b/srml/chainrelay/Cargo.toml
@@ -0,0 +1,22 @@
+[package]
+name = "darwinia-chainrelay"
+version = "0.1.0"
+authors = ["hammeWang <dsw0602@foxmail.com>"]
+edition = "2018"
+
+# See more keys and their definitions at https://doc.rust-lang.org/cargo/reference/manifest.html
+
+[dependencies]
+rstd = { package = "sr-std", git = 'https://github.com/paritytech/substrate.git', default-features = false }
+support = { package = "srml-support", git = 'https://github.com/paritytech/substrate.git', default-features = false }
+system = { package = "srml-system",  git = 'https://github.com/paritytech/substrate.git', default-features = false }
+poa = { package = "darwinia-chainrelay-poa", path = "../chainrelay/poa", default-features = false }
+
+[features]
+default = ["std"]
+std = [
+    "rstd/std",
+    "support/std",
+    "system/std",
+    "poa/std",
+]
\ No newline at end of file
diff --git a/srml/chainrelay/poa/Cargo.toml b/srml/chainrelay/poa/Cargo.toml
new file mode 100644
index 000000000..252e715c9
--- /dev/null
+++ b/srml/chainrelay/poa/Cargo.toml
@@ -0,0 +1,14 @@
+[package]
+name = "darwinia-chainrelay-poa"
+version = "0.1.0"
+authors = ["hammeWang <dsw0602@foxmail.com>"]
+edition = "2018"
+
+# See more keys and their definitions at https://doc.rust-lang.org/cargo/reference/manifest.html
+
+[dependencies]
+
+
+[features]
+default = ["std"]
+std = []
\ No newline at end of file
diff --git a/srml/chainrelay/poa/src/lib.rs b/srml/chainrelay/poa/src/lib.rs
new file mode 100644
index 000000000..69529b312
--- /dev/null
+++ b/srml/chainrelay/poa/src/lib.rs
@@ -0,0 +1,4 @@
+pub struct BestHeader<Hash> {
+	height: u64, // enough for ethereum poa network (kovan)
+	hash: Hash,
+}
diff --git a/srml/chainrelay/src/lib.rs b/srml/chainrelay/src/lib.rs
new file mode 100644
index 000000000..acc6c9867
--- /dev/null
+++ b/srml/chainrelay/src/lib.rs
@@ -0,0 +1,21 @@
+//!  prototype module for bridging in ethereum poa blockcahin
+
+#![recursion_limit = "128"]
+#![cfg_attr(not(feature = "std"), no_std)]
+
+use rstd::prelude::*;
+use support::{decl_event, decl_module, decl_storage, ensure};
+
+use poa::BestHeader;
+
+pub trait Trait: system::Trait {}
+
+decl_storage! {
+	trait Store for Module<T: Trait> as Bridge {
+		// we don't need to start from genesis block
+		pub InitialBlock get(initial_block) config(): T::BlockNumber;
+		// BestHeader
+		pub BestHeader get(best_header): BestHeader;
+
+	}
+}