diff --git a/bin/full-node/src/run.rs b/bin/full-node/src/run.rs
index 3a847d8d3c..19a4f6e219 100644
--- a/bin/full-node/src/run.rs
+++ b/bin/full-node/src/run.rs
@@ -223,6 +223,7 @@ pub async fn run(cli_options: cli::CliOptionsRun) {
             num_events_receivers: 2 + if relay_chain_database.is_some() { 1 } else { 0 },
             chains: iter::once(network_service::ChainConfig {
                 protocol_id: chain_spec.protocol_id().to_owned(),
+                fork_id: chain_spec.fork_id().map(|s| s.to_owned()),
                 database: database.clone(),
                 has_grandpa_protocol: matches!(
                     genesis_chain_information.finality,
@@ -260,6 +261,7 @@ pub async fn run(cli_options: cli::CliOptionsRun) {
                 if let Some(relay_chains_specs) = &relay_chain_spec {
                     Some(network_service::ChainConfig {
                         protocol_id: relay_chains_specs.protocol_id().to_owned(),
+                        fork_id: relay_chains_specs.fork_id().map(|s| s.to_owned()),
                         database: relay_chain_database.clone().unwrap(),
                         has_grandpa_protocol: matches!(
                             relay_genesis_chain_information.as_ref().unwrap().finality,
diff --git a/bin/full-node/src/run/network_service.rs b/bin/full-node/src/run/network_service.rs
index 1dedbb8f37..e091782e76 100644
--- a/bin/full-node/src/run/network_service.rs
+++ b/bin/full-node/src/run/network_service.rs
@@ -97,6 +97,11 @@ pub struct ChainConfig {
     /// chain, so as to not introduce conflicts in the networking messages.
     pub protocol_id: String,
 
+    /// Optional fork identifier, used to differentiate between chains with the same genesis hash.
+    ///
+    /// This can be a counter (e.g. "1", "2", "3") or some unique identifier (e.g. "classic").
+    pub fork_id: Option<String>,
+
     /// If true, the chain uses the GrandPa networking protocol.
     pub has_grandpa_protocol: bool,
 }
@@ -160,6 +165,7 @@ impl NetworkService {
                 in_slots: 25,
                 out_slots: 25,
                 protocol_id: chain.protocol_id.clone(),
+                fork_id: chain.fork_id.clone(),
                 best_hash: chain.best_block.1,
                 best_number: chain.best_block.0,
                 genesis_hash: chain.genesis_block_hash,
diff --git a/bin/light-base/src/network_service.rs b/bin/light-base/src/network_service.rs
index 0fd57d8206..128b30f054 100644
--- a/bin/light-base/src/network_service.rs
+++ b/bin/light-base/src/network_service.rs
@@ -98,6 +98,11 @@ pub struct ConfigChain {
     /// chain, so as to not introduce conflicts in the networking messages.
     pub protocol_id: String,
 
+    /// Optional fork identifier, used to differentiate between chains with the same genesis hash.
+    ///
+    /// This can be a counter (e.g. "1", "2", "3") or some unique identifier (e.g. "classic").
+    pub fork_id: Option<String>,
+
     /// If true, the chain uses the GrandPa networking protocol.
     pub has_grandpa_protocol: bool,
 }
@@ -153,6 +158,7 @@ impl<TPlat: Platform> NetworkService<TPlat> {
                     None
                 },
                 protocol_id: chain.protocol_id.clone(),
+                fork_id: chain.fork_id.clone(),
                 best_hash: chain.best_block.1,
                 best_number: chain.best_block.0,
                 genesis_hash: chain.genesis_block_hash,
diff --git a/src/network/service.rs b/src/network/service.rs
index be828a0066..b3f8c77a9d 100644
--- a/src/network/service.rs
+++ b/src/network/service.rs
@@ -16,6 +16,7 @@
 // along with this program.  If not, see <http://www.gnu.org/licenses/>.
 
 use crate::header;
+use crate::informant::HashDisplay;
 use crate::libp2p::{
     connection, multiaddr, peer_id,
     peers::{self, QueueNotificationError},
@@ -119,6 +120,12 @@ pub struct ChainConfig {
     /// >           "chain spec").
     pub protocol_id: String,
 
+    /// Optional fork identifier, used to differentiate between chains with the same genesis hash.
+    ///
+    /// > **Note**: This value is typically found in the specification of the chain (the
+    /// >           "chain spec").
+    pub fork_id: Option<String>,
+
     /// If `Some`, the chain uses the GrandPa networking protocol.
     pub grandpa_protocol_config: Option<GrandpaState>,
 
@@ -282,7 +289,12 @@ where
                     // chains, in order to make the rest of the code of this module more
                     // comprehensible.
                     iter::once(peers::NotificationProtocolConfig {
-                        protocol_name: "/paritytech/grandpa/1".to_string(),
+                        protocol_name: match &chain.fork_id {
+                            Some(id) => {
+                                format!("/{}/{}/grandpa/1", HashDisplay(&chain.genesis_hash), id)
+                            }
+                            None => format!("/{}/grandpa/1", HashDisplay(&chain.genesis_hash)),
+                        },
                         fallback_protocol_names: Vec::new(),
                         max_handshake_size: 4,
                         max_notification_size: 1024 * 1024,