Add default_rpc_port method to NetworkExt trait

diff --git a/p2p/src/network_ext.rs b/p2p/src/network_ext.rs
index 93aee0ab..0a5051ce 100644
--- a/p2p/src/network_ext.rs
+++ b/p2p/src/network_ext.rs
@@ -15,6 +15,9 @@ pub trait NetworkExt {
 
     /// The default network [`Magic`] for a given [`Network`].
     fn default_network_magic(self) -> Magic;
+
+    /// Returns the default RPC port for the given network.
+    fn default_rpc_port(&self) -> u16;
 }
 
 impl NetworkExt for Network {
@@ -33,6 +36,20 @@ impl NetworkExt for Network {
         }
     }
 
+    /// The default RPC port for a given [`Network`].
+    ///
+    /// Note: All [`TestnetVersion`] variants >4 are treated as [`TestnetVersion::V4`].
+    /// This function will be updated as new test networks are defined.
+    fn default_rpc_port(&self) -> u16 {
+        match self {
+            Self::Bitcoin => 8332,
+            Self::Signet => 38332,
+            Self::Testnet(TestnetVersion::V3) => 18332,
+            Self::Testnet(TestnetVersion::V4 | _) => 48332,
+            Self::Regtest => 18442,
+        }
+    }
+
     /// The default network [`Magic`] for a given [`Network`].
     ///
     /// Note: All [`TestnetVersion`] variants >4 are treated as [`TestnetVersion::V4`].
@@ -55,6 +72,23 @@ mod tests {
 
     use super::*;
 
+    #[test]
+    fn default_rpc_port() {
+        let networks = [
+            Network::Bitcoin,
+            Network::Signet,
+            Network::Testnet(TestnetVersion::V3),
+            Network::Testnet(TestnetVersion::V4),
+            Network::Regtest,
+        ];
+
+        let rpc_ports = vec![8332, 38332, 18332, 48332, 18442];
+
+        for (network, rpc_port) in networks.iter().zip(rpc_ports) {
+            assert_eq!(network.default_rpc_port(), rpc_port);
+        }
+    }
+
     #[test]
     fn default_p2p_port() {
         let networks = [