diff --git a/kernel/aster-nix/src/net/socket/ip/stream/connected.rs b/kernel/aster-nix/src/net/socket/ip/stream/connected.rs
index e26e3d9de..3a70f2c97 100644
--- a/kernel/aster-nix/src/net/socket/ip/stream/connected.rs
+++ b/kernel/aster-nix/src/net/socket/ip/stream/connected.rs
@@ -68,6 +68,26 @@ impl ConnectedStream {
         self.update_io_events(pollee);
     }
 
+    pub fn register_observer(
+        &self,
+        pollee: &Pollee,
+        observer: Weak<dyn Observer<IoEvents>>,
+        mask: IoEvents,
+    ) -> Result<()> {
+        pollee.register_observer(observer, mask);
+        Ok(())
+    }
+
+    pub fn unregister_observer(
+        &self,
+        pollee: &Pollee,
+        observer: &Weak<dyn Observer<IoEvents>>,
+    ) -> Result<Weak<dyn Observer<IoEvents>>> {
+        pollee
+            .unregister_observer(observer)
+            .ok_or_else(|| Error::with_message(Errno::EINVAL, "fails to unregister observer"))
+    }
+
     pub(super) fn update_io_events(&self, pollee: &Pollee) {
         self.bound_socket.raw_with(|socket: &mut RawTcpSocket| {
             if socket.can_recv() {
diff --git a/kernel/aster-nix/src/net/socket/ip/stream/connecting.rs b/kernel/aster-nix/src/net/socket/ip/stream/connecting.rs
index d1ac85383..2af4eb24f 100644
--- a/kernel/aster-nix/src/net/socket/ip/stream/connecting.rs
+++ b/kernel/aster-nix/src/net/socket/ip/stream/connecting.rs
@@ -2,7 +2,7 @@
 
 use super::{connected::ConnectedStream, init::InitStream};
 use crate::{
-    events::IoEvents,
+    events::{IoEvents, Observer},
     net::iface::{AnyBoundSocket, IpEndpoint, RawTcpSocket},
     prelude::*,
     process::signal::Pollee,
@@ -71,6 +71,26 @@ impl ConnectingStream {
         self.update_io_events(pollee);
     }
 
+    pub fn register_observer(
+        &self,
+        pollee: &Pollee,
+        observer: Weak<dyn Observer<IoEvents>>,
+        mask: IoEvents,
+    ) -> Result<()> {
+        pollee.register_observer(observer, mask);
+        Ok(())
+    }
+
+    pub fn unregister_observer(
+        &self,
+        pollee: &Pollee,
+        observer: &Weak<dyn Observer<IoEvents>>,
+    ) -> Result<Weak<dyn Observer<IoEvents>>> {
+        pollee
+            .unregister_observer(observer)
+            .ok_or_else(|| Error::with_message(Errno::EINVAL, "fails to unregister observer"))
+    }
+
     pub(super) fn update_io_events(&self, pollee: &Pollee) {
         if self.conn_result.read().is_some() {
             return;
diff --git a/kernel/aster-nix/src/net/socket/ip/stream/init.rs b/kernel/aster-nix/src/net/socket/ip/stream/init.rs
index 352237a9c..3f8626b32 100644
--- a/kernel/aster-nix/src/net/socket/ip/stream/init.rs
+++ b/kernel/aster-nix/src/net/socket/ip/stream/init.rs
@@ -4,12 +4,13 @@ use alloc::sync::Weak;
 
 use super::{connecting::ConnectingStream, listen::ListenStream};
 use crate::{
-    events::Observer,
+    events::{IoEvents, Observer},
     net::{
         iface::{AnyBoundSocket, AnyUnboundSocket, IpEndpoint},
         socket::ip::common::{bind_socket, get_ephemeral_endpoint},
     },
     prelude::*,
+    process::signal::Pollee,
 };
 
 pub enum InitStream {
@@ -90,4 +91,24 @@ impl InitStream {
             InitStream::Bound(bound_socket) => Ok(bound_socket.local_endpoint().unwrap()),
         }
     }
+
+    pub fn register_observer(
+        &self,
+        pollee: &Pollee,
+        observer: Weak<dyn Observer<IoEvents>>,
+        mask: IoEvents,
+    ) -> Result<()> {
+        pollee.register_observer(observer, mask);
+        Ok(())
+    }
+
+    pub fn unregister_observer(
+        &self,
+        pollee: &Pollee,
+        observer: &Weak<dyn Observer<IoEvents>>,
+    ) -> Result<Weak<dyn Observer<IoEvents>>> {
+        pollee
+            .unregister_observer(observer)
+            .ok_or_else(|| Error::with_message(Errno::EINVAL, "fails to unregister observer"))
+    }
 }
diff --git a/kernel/aster-nix/src/net/socket/ip/stream/listen.rs b/kernel/aster-nix/src/net/socket/ip/stream/listen.rs
index a970eaea1..239d9ae9b 100644
--- a/kernel/aster-nix/src/net/socket/ip/stream/listen.rs
+++ b/kernel/aster-nix/src/net/socket/ip/stream/listen.rs
@@ -2,7 +2,7 @@
 
 use super::connected::ConnectedStream;
 use crate::{
-    events::IoEvents,
+    events::{IoEvents, Observer},
     net::iface::{AnyBoundSocket, AnyUnboundSocket, BindPortConfig, IpEndpoint, RawTcpSocket},
     prelude::*,
     process::signal::Pollee,
@@ -92,6 +92,26 @@ impl ListenStream {
             pollee.del_events(IoEvents::IN);
         }
     }
+
+    pub fn register_observer(
+        &self,
+        pollee: &Pollee,
+        observer: Weak<dyn Observer<IoEvents>>,
+        mask: IoEvents,
+    ) -> Result<()> {
+        pollee.register_observer(observer, mask);
+        Ok(())
+    }
+
+    pub fn unregister_observer(
+        &self,
+        pollee: &Pollee,
+        observer: &Weak<dyn Observer<IoEvents>>,
+    ) -> Result<Weak<dyn Observer<IoEvents>>> {
+        pollee
+            .unregister_observer(observer)
+            .ok_or_else(|| Error::with_message(Errno::EINVAL, "fails to unregister observer"))
+    }
 }
 
 struct BacklogSocket {
diff --git a/kernel/aster-nix/src/net/socket/ip/stream/mod.rs b/kernel/aster-nix/src/net/socket/ip/stream/mod.rs
index 32b95e52a..8091fcd78 100644
--- a/kernel/aster-nix/src/net/socket/ip/stream/mod.rs
+++ b/kernel/aster-nix/src/net/socket/ip/stream/mod.rs
@@ -275,6 +275,36 @@ impl FileLike for StreamSocket {
     fn as_socket(self: Arc<Self>) -> Option<Arc<dyn Socket>> {
         Some(self)
     }
+
+    fn register_observer(
+        &self,
+        observer: Weak<dyn crate::events::Observer<IoEvents>>,
+        mask: IoEvents,
+    ) -> Result<()> {
+        let state = self.state.read();
+        match state.as_ref() {
+            State::Init(init) => init.register_observer(&self.pollee, observer, mask),
+            State::Connecting(connecting) => {
+                connecting.register_observer(&self.pollee, observer, mask)
+            }
+            State::Connected(connected) => {
+                connected.register_observer(&self.pollee, observer, mask)
+            }
+            State::Listen(listen) => listen.register_observer(&self.pollee, observer, mask),
+        }
+    }
+
+    fn unregister_observer(
+        &self,
+        observer: &Weak<dyn crate::events::Observer<IoEvents>>,
+    ) -> Result<Weak<dyn crate::events::Observer<IoEvents>>> {
+        match self.state.read().as_ref() {
+            State::Init(init) => init.unregister_observer(&self.pollee, observer),
+            State::Connecting(connecting) => connecting.unregister_observer(&self.pollee, observer),
+            State::Connected(connected) => connected.unregister_observer(&self.pollee, observer),
+            State::Listen(listen) => listen.unregister_observer(&self.pollee, observer),
+        }
+    }
 }
 
 impl Socket for StreamSocket {
diff --git a/kernel/aster-nix/src/net/socket/options/mod.rs b/kernel/aster-nix/src/net/socket/options/mod.rs
index 0332180c2..b5df5a857 100644
--- a/kernel/aster-nix/src/net/socket/options/mod.rs
+++ b/kernel/aster-nix/src/net/socket/options/mod.rs
@@ -19,4 +19,5 @@ impl_socket_options!(
     pub struct RecvBuf(u32);
     pub struct Error(Option<crate::error::Error>);
     pub struct Linger(LingerOption);
+    pub struct KeepAlive(bool);
 );
diff --git a/kernel/aster-nix/src/net/socket/util/options.rs b/kernel/aster-nix/src/net/socket/util/options.rs
index 023c080d3..b72ea92ca 100644
--- a/kernel/aster-nix/src/net/socket/util/options.rs
+++ b/kernel/aster-nix/src/net/socket/util/options.rs
@@ -17,6 +17,7 @@ pub struct SocketOptionSet {
     send_buf: u32,
     recv_buf: u32,
     linger: LingerOption,
+    keep_alive: bool,
 }
 
 impl SocketOptionSet {
@@ -29,6 +30,7 @@ impl SocketOptionSet {
             send_buf: SEND_BUF_LEN as u32,
             recv_buf: RECV_BUF_LEN as u32,
             linger: LingerOption::default(),
+            keep_alive: false,
         }
     }
 }
diff --git a/kernel/aster-nix/src/util/net/options/socket.rs b/kernel/aster-nix/src/util/net/options/socket.rs
index 79ed26ecb..7c1ac1b8d 100644
--- a/kernel/aster-nix/src/util/net/options/socket.rs
+++ b/kernel/aster-nix/src/util/net/options/socket.rs
@@ -5,7 +5,9 @@ use aster_rights::Full;
 use super::RawSocketOption;
 use crate::{
     impl_raw_sock_option_get_only, impl_raw_socket_option,
-    net::socket::options::{Error, Linger, RecvBuf, ReuseAddr, ReusePort, SendBuf, SocketOption},
+    net::socket::options::{
+        Error, KeepAlive, Linger, RecvBuf, ReuseAddr, ReusePort, SendBuf, SocketOption,
+    },
     prelude::*,
     vm::vmar::Vmar,
 };
@@ -48,6 +50,7 @@ pub fn new_socket_option(name: i32) -> Result<Box<dyn RawSocketOption>> {
         CSocketOptionName::ERROR => Ok(Box::new(Error::new())),
         CSocketOptionName::REUSEPORT => Ok(Box::new(ReusePort::new())),
         CSocketOptionName::LINGER => Ok(Box::new(Linger::new())),
+        CSocketOptionName::KEEPALIVE => Ok(Box::new(KeepAlive::new())),
         _ => todo!(),
     }
 }
@@ -58,3 +61,4 @@ impl_raw_socket_option!(ReuseAddr);
 impl_raw_sock_option_get_only!(Error);
 impl_raw_socket_option!(ReusePort);
 impl_raw_socket_option!(Linger);
+impl_raw_socket_option!(KeepAlive);