diff --git a/Cargo.lock b/Cargo.lock
index f9116da..6e790fc 100644
--- a/Cargo.lock
+++ b/Cargo.lock
@@ -3850,6 +3850,7 @@ dependencies = [
  "mpart-async",
  "nix",
  "openssl",
+ "parity-scale-codec",
  "prometheus",
  "protobuf 3.3.0",
  "protobuf-codegen",
diff --git a/Cargo.toml b/Cargo.toml
index 41cb188..adf8287 100644
--- a/Cargo.toml
+++ b/Cargo.toml
@@ -38,7 +38,8 @@ url = "2.3.1"
 tokio-tungstenite = { version = "0.20", features = ["native-tls"] }
 futures-util = "0.3.25"
 jwt = "0.16"
-subxt = "0.28.0"
+subxt = { version = "0.28.0", features = ["substrate-compat"]}
+codec = { package = "parity-scale-codec", version = "3.0.0", default-features = false, features = ["derive", "full", "bit-vec"] }
 itertools = "0.11"
 
 # for static build
diff --git a/_tests/e2e_tests.rs b/_tests/e2e_tests.rs
index 90eecf5..685aa0f 100644
--- a/_tests/e2e_tests.rs
+++ b/_tests/e2e_tests.rs
@@ -44,6 +44,9 @@ impl TwinDB for InMemoryDB {
     ) -> anyhow::Result<Option<u32>> {
         unimplemented!()
     }
+    async fn set_twin(&self, twin: Twin) -> anyhow::Result<()> {
+        unimplemented!()
+    }
 }
 
 fn new_message(
diff --git a/artifacts/network.scale b/artifacts/network.scale
new file mode 100644
index 0000000..d9891b7
Binary files /dev/null and b/artifacts/network.scale differ
diff --git a/proto/types.proto b/proto/types.proto
index 8e9cedb..e7ba3bf 100644
--- a/proto/types.proto
+++ b/proto/types.proto
@@ -71,4 +71,6 @@ message Envelope {
     bytes plain = 13;
     bytes cipher = 14;
   }
+
+  optional string relays = 17;
 }
diff --git a/src/bins/rmb-peer.rs b/src/bins/rmb-peer.rs
index c62c4dc..8c39e06 100644
--- a/src/bins/rmb-peer.rs
+++ b/src/bins/rmb-peer.rs
@@ -1,6 +1,5 @@
 use std::path::PathBuf;
 use std::str::FromStr;
-use std::time::Duration;
 
 use anyhow::{Context, Result};
 use clap::{builder::ArgAction, Args, Parser};
@@ -151,12 +150,10 @@ async fn app(args: Params) -> Result<()> {
 
     // cache is a little bit tricky because while it improves performance it
     // makes changes to twin data takes at least 5 min before they are detected
-    let db = SubstrateTwinDB::<RedisCache>::new(
-        args.substrate,
-        RedisCache::new(pool.clone(), "twin", Duration::from_secs(60)),
-    )
-    .await
-    .context("cannot create substrate twin db object")?;
+    let db =
+        SubstrateTwinDB::<RedisCache>::new(args.substrate, RedisCache::new(pool.clone(), "twin"))
+            .await
+            .context("cannot create substrate twin db object")?;
 
     let id = db
         .get_twin_with_account(signer.account())
diff --git a/src/bins/rmb-relay.rs b/src/bins/rmb-relay.rs
index 1732bed..a00230c 100644
--- a/src/bins/rmb-relay.rs
+++ b/src/bins/rmb-relay.rs
@@ -4,6 +4,7 @@ use std::time::Duration;
 use anyhow::{Context, Result};
 use clap::{builder::ArgAction, Parser};
 use rmb::cache::RedisCache;
+use rmb::events;
 use rmb::redis;
 use rmb::relay::{
     self,
@@ -142,14 +143,13 @@ async fn app(args: Args) -> Result<()> {
         .await
         .context("failed to initialize redis pool")?;
 
-    // we use 6 hours cache for twin information because twin id will not change anyway
-    // and we only need twin public key for validation only.
-    let twins = SubstrateTwinDB::<RedisCache>::new(
-        args.substrate,
-        RedisCache::new(pool.clone(), "twin", Duration::from_secs(args.cache * 60)),
-    )
-    .await
-    .context("cannot create substrate twin db object")?;
+    let redis_cache = RedisCache::new(pool.clone(), "twin");
+
+    redis_cache.flush().await?;
+
+    let twins = SubstrateTwinDB::<RedisCache>::new(args.substrate.clone(), redis_cache.clone())
+        .await
+        .context("cannot create substrate twin db object")?;
 
     let max_users = args.workers as usize * args.user_per_worker as usize;
     let opt = relay::SwitchOptions::new(pool.clone())
@@ -175,6 +175,14 @@ async fn app(args: Args) -> Result<()> {
     let r = relay::Relay::new(&args.domain, twins, opt, federation, limiter, ranker)
         .await
         .unwrap();
+
+    let l = events::Listener::new(args.substrate[0].as_str(), redis_cache).await?;
+    tokio::spawn(async move {
+        if let Err(e) = l.listen().await {
+            log::error!("failed to listen to events: {:#}", e);
+        }
+    });
+
     r.start(&args.listen).await.unwrap();
     Ok(())
 }
diff --git a/src/cache/redis.rs b/src/cache/redis.rs
index 13320f2..33d9b31 100644
--- a/src/cache/redis.rs
+++ b/src/cache/redis.rs
@@ -1,5 +1,3 @@
-use std::time::Duration;
-
 use super::Cache;
 
 use anyhow::{Context, Result};
@@ -22,19 +20,13 @@ use serde::{de::DeserializeOwned, Serialize};
 pub struct RedisCache {
     pool: Pool<RedisConnectionManager>,
     prefix: String,
-    ttl: Duration,
 }
 
 impl RedisCache {
-    pub fn new<P: Into<String>>(
-        pool: Pool<RedisConnectionManager>,
-        prefix: P,
-        ttl: Duration,
-    ) -> Self {
+    pub fn new<P: Into<String>>(pool: Pool<RedisConnectionManager>, prefix: P) -> Self {
         Self {
             pool,
             prefix: prefix.into(),
-            ttl,
         }
     }
 
@@ -47,6 +39,12 @@ impl RedisCache {
 
         Ok(conn)
     }
+    pub async fn flush(&self) -> Result<()> {
+        let mut conn = self.get_connection().await?;
+        cmd("DEL").arg(&self.prefix).query_async(&mut *conn).await?;
+
+        Ok(())
+    }
 }
 
 #[async_trait]
@@ -57,12 +55,10 @@ where
     async fn set<S: ToString + Send + Sync>(&self, key: S, obj: T) -> Result<()> {
         let mut conn = self.get_connection().await?;
         let obj = serde_json::to_vec(&obj).context("unable to serialize twin object for redis")?;
-        let key = format!("{}.{}", self.prefix, key.to_string());
-        cmd("SET")
-            .arg(key)
+        cmd("HSET")
+            .arg(&self.prefix)
+            .arg(key.to_string())
             .arg(obj)
-            .arg("EX")
-            .arg(self.ttl.as_secs())
             .query_async(&mut *conn)
             .await?;
 
@@ -70,9 +66,12 @@ where
     }
     async fn get<S: ToString + Send + Sync>(&self, key: S) -> Result<Option<T>> {
         let mut conn = self.get_connection().await?;
-        let key = format!("{}.{}", self.prefix, key.to_string());
 
-        let ret: Option<Vec<u8>> = cmd("GET").arg(key).query_async(&mut *conn).await?;
+        let ret: Option<Vec<u8>> = cmd("HGET")
+            .arg(&self.prefix)
+            .arg(key.to_string())
+            .query_async(&mut *conn)
+            .await?;
 
         match ret {
             Some(val) => {
@@ -93,7 +92,6 @@ mod tests {
     use super::*;
 
     const PREFIX: &str = "twin";
-    const TTL: u64 = 20;
 
     async fn create_redis_cache() -> RedisCache {
         let manager = RedisConnectionManager::new("redis://127.0.0.1/")
@@ -105,7 +103,7 @@ mod tests {
             .context("unable to build pool or redis connection manager")
             .unwrap();
 
-        RedisCache::new(pool, PREFIX, Duration::from_secs(TTL))
+        RedisCache::new(pool, PREFIX)
     }
 
     #[tokio::test]
diff --git a/src/events/events.rs b/src/events/events.rs
new file mode 100644
index 0000000..cd8fffb
--- /dev/null
+++ b/src/events/events.rs
@@ -0,0 +1,43 @@
+use crate::{cache::Cache, tfchain::tfchain, twin::Twin};
+use anyhow::Result;
+use futures::StreamExt;
+use log;
+use subxt::{OnlineClient, PolkadotConfig};
+
+#[derive(Clone)]
+pub struct Listener<C>
+where
+    C: Cache<Twin>,
+{
+    cache: C,
+    api: OnlineClient<PolkadotConfig>,
+}
+
+impl<C> Listener<C>
+where
+    C: Cache<Twin> + Clone,
+{
+    pub async fn new(url: &str, cache: C) -> Result<Self> {
+        let api = OnlineClient::<PolkadotConfig>::from_url(url).await?;
+        Ok(Listener { api, cache })
+    }
+    pub async fn listen(&self) -> Result<()> {
+        log::info!("started chain events listener");
+        let mut blocks_sub = self.api.blocks().subscribe_finalized().await?;
+        while let Some(block) = blocks_sub.next().await {
+            let events = block?.events().await?;
+            for evt in events.iter() {
+                let evt = evt?;
+                if let Ok(Some(twin)) = evt.as_event::<tfchain::tfgrid_module::events::TwinStored>()
+                {
+                    self.cache.set(twin.0.id, twin.0.into()).await?;
+                } else if let Ok(Some(twin)) =
+                    evt.as_event::<tfchain::tfgrid_module::events::TwinUpdated>()
+                {
+                    self.cache.set(twin.0.id, twin.0.into()).await?;
+                }
+            }
+        }
+        Ok(())
+    }
+}
diff --git a/src/events/mod.rs b/src/events/mod.rs
new file mode 100644
index 0000000..3a34494
--- /dev/null
+++ b/src/events/mod.rs
@@ -0,0 +1,3 @@
+mod events;
+
+pub use events::Listener;
diff --git a/src/lib.rs b/src/lib.rs
index 71e0a38..e3e063e 100644
--- a/src/lib.rs
+++ b/src/lib.rs
@@ -3,10 +3,12 @@ extern crate anyhow;
 extern crate mime;
 
 pub mod cache;
+pub mod events;
 pub mod identity;
 pub mod peer;
 pub mod redis;
 pub mod relay;
+pub mod tfchain;
 pub mod token;
 pub mod twin;
 pub mod types;
diff --git a/src/relay/api.rs b/src/relay/api.rs
index 0c86fbd..c8e61db 100644
--- a/src/relay/api.rs
+++ b/src/relay/api.rs
@@ -1,5 +1,5 @@
 use crate::token::{self, Claims};
-use crate::twin::TwinDB;
+use crate::twin::{RelayDomains, TwinDB};
 use crate::types::{Envelope, EnvelopeExt, Pong};
 use anyhow::{Context, Result};
 use futures::stream::SplitSink;
@@ -17,6 +17,7 @@ use prometheus::TextEncoder;
 use protobuf::Message as ProtoMessage;
 use std::fmt::Display;
 use std::pin::Pin;
+use std::str::FromStr;
 use std::sync::Arc;
 use tokio::sync::Mutex;
 
@@ -203,6 +204,27 @@ async fn federation<D: TwinDB, R: RateLimiter>(
     let envelope =
         Envelope::parse_from_bytes(&body).map_err(|err| HttpError::BadRequest(err.to_string()))?;
 
+    if let Some(relays) = &envelope.relays {
+        let mut twin = data
+            .twins
+            .get_twin(envelope.source.twin)
+            .await
+            .map_err(|err| HttpError::FailedToGetTwin(err.to_string()))?
+            .ok_or_else(|| HttpError::TwinNotFound(envelope.source.twin))?;
+        let envelope_relays = match RelayDomains::from_str(relays) {
+            Ok(r) => r,
+            Err(_) => return Err(HttpError::BadRequest("invalid relays".to_string())),
+        };
+        if let Some(twin_relays) = twin.relay {
+            if twin_relays != envelope_relays {
+                twin.relay = Some(envelope_relays);
+                data.twins
+                    .set_twin(twin)
+                    .await
+                    .map_err(|err| HttpError::FailedToSetTwin(err.to_string()))?;
+            }
+        }
+    }
     let dst: StreamID = (&envelope.destination).into();
     data.switch.send(&dst, &body).await?;
 
@@ -309,6 +331,25 @@ impl<M: Metrics, D: TwinDB> Stream<M, D> {
             .await?
             .ok_or_else(|| anyhow::Error::msg("unknown twin destination"))?;
 
+        if let Some(relays) = &envelope.relays {
+            let mut twin = self
+                .twins
+                .get_twin(envelope.source.twin)
+                .await?
+                .ok_or_else(|| anyhow::Error::msg("unknown twin source"))?;
+
+            let envelope_relays = match RelayDomains::from_str(relays) {
+                Ok(r) => r,
+                Err(_) => anyhow::bail!("invalid relays"),
+            };
+            if let Some(twin_relays) = twin.relay {
+                if twin_relays != envelope_relays {
+                    twin.relay = Some(envelope_relays);
+                    self.twins.set_twin(twin.clone()).await?;
+                }
+            }
+        }
+
         if !twin
             .relay
             .ok_or_else(|| anyhow::Error::msg("relay info is not set for this twin"))?
diff --git a/src/relay/mod.rs b/src/relay/mod.rs
index df6532b..15db835 100644
--- a/src/relay/mod.rs
+++ b/src/relay/mod.rs
@@ -87,6 +87,8 @@ pub enum HttpError {
     InvalidJWT(#[from] token::Error),
     #[error("failed to get twin: {0}")]
     FailedToGetTwin(String),
+    #[error("failed to set twin: {0}")]
+    FailedToSetTwin(String),
     #[error("twin not found {0}")]
     TwinNotFound(u32),
     #[error("{0}")]
@@ -109,6 +111,7 @@ impl HttpError {
             Self::MissingJWT => Codes::BAD_REQUEST,
             Self::InvalidJWT(_) => Codes::UNAUTHORIZED,
             Self::FailedToGetTwin(_) => Codes::INTERNAL_SERVER_ERROR,
+            Self::FailedToSetTwin(_) => Codes::INTERNAL_SERVER_ERROR,
             Self::TwinNotFound(_) => Codes::UNAUTHORIZED,
             Self::WebsocketError(_) => Codes::INTERNAL_SERVER_ERROR,
             Self::NotFound => Codes::NOT_FOUND,
diff --git a/src/tfchain/mod.rs b/src/tfchain/mod.rs
new file mode 100644
index 0000000..0832754
--- /dev/null
+++ b/src/tfchain/mod.rs
@@ -0,0 +1,6 @@
+#[subxt::subxt(runtime_metadata_path = "artifacts/network.scale")]
+mod tfchain {}
+
+use subxt::utils::AccountId32;
+pub use tfchain::runtime_types::pallet_tfgrid::types::Twin as TwinData;
+pub type Twin = TwinData<AccountId32>;
diff --git a/src/twin/mod.rs b/src/twin/mod.rs
index 17f2e63..a91edf1 100644
--- a/src/twin/mod.rs
+++ b/src/twin/mod.rs
@@ -15,10 +15,13 @@ use subxt::utils::AccountId32;
 pub trait TwinDB: Send + Sync + Clone + 'static {
     async fn get_twin(&self, twin_id: u32) -> Result<Option<Twin>>;
     async fn get_twin_with_account(&self, account_id: AccountId32) -> Result<Option<u32>>;
+    async fn set_twin(&self, twin: Twin) -> Result<()>;
 }
 
 use tfchain_client::client::Twin as TwinData;
 
+use crate::tfchain;
+
 #[derive(Serialize, Deserialize, Debug, Clone, Eq, PartialEq)]
 pub struct Twin {
     pub id: u32,
@@ -41,6 +44,20 @@ impl From<TwinData> for Twin {
     }
 }
 
+impl From<tfchain::Twin> for Twin {
+    fn from(twin: tfchain::Twin) -> Self {
+        Twin {
+            id: twin.id,
+            account: twin.account_id,
+            relay: twin.relay.map(|v| {
+                let string: String = String::from_utf8_lossy(&v.0).into();
+                RelayDomains::from_str(&string).unwrap_or_default()
+            }),
+            pk: twin.pk.map(|v| v.0),
+        }
+    }
+}
+
 #[derive(Debug, Clone, Serialize, Deserialize, PartialEq, Default, Eq)]
 pub struct RelayDomains(HashSet<String>);
 
diff --git a/src/twin/substrate.rs b/src/twin/substrate.rs
index cf7b018..7ac9d21 100644
--- a/src/twin/substrate.rs
+++ b/src/twin/substrate.rs
@@ -78,6 +78,11 @@ where
 
         Ok(id)
     }
+
+    async fn set_twin(&self, twin: Twin) -> Result<()> {
+        self.cache.set(twin.id, twin).await?;
+        Ok(())
+    }
 }
 
 /// ClientWrapper is basically a substrate client.
diff --git a/src/types/mod.rs b/src/types/mod.rs
index ab26689..71dc005 100644
--- a/src/types/mod.rs
+++ b/src/types/mod.rs
@@ -338,6 +338,9 @@ impl Challengeable for Envelope {
                 hash.write_all(data)?;
             }
         }
+        if let Some(ref relays) = self.relays {
+            write!(hash, "{}", relays)?;
+        }
 
         Ok(())
     }