diff --git a/sas4-l2tp-full-installer.sh b/sas4-l2tp-full-installer.sh
new file mode 100644
index 0000000..f9b9856
--- /dev/null
+++ b/sas4-l2tp-full-installer.sh
@@ -0,0 +1,98 @@
+#!/bin/bash
+
+# Update the system
+sudo apt update && sudo apt upgrade -y
+
+# Install required packages
+sudo apt install strongswan xl2tpd -y
+
+# Configure strongSwan
+sudo bash -c 'cat > /etc/ipsec.conf <<EOF
+config setup
+    charondebug="ike 2, knl 2, cfg 2"
+
+conn %default
+    ikelifetime=60m
+    keylife=20m
+    rekeymargin=3m
+    keyingtries=1
+    authby=secret
+    keyexchange=ikev1
+    ike=aes256-sha1-modp1024!
+    esp=aes256-sha1!
+
+conn L2TP-PSK
+    keyexchange=ikev1
+    left=%any
+    leftprotoport=17/1701
+    leftfirewall=yes
+    right=%any
+    rightprotoport=17/%any
+    auto=add
+EOF'
+
+# Configure IPsec secrets
+sudo bash -c 'cat > /etc/ipsec.secrets <<EOF
+: PSK "123456"
+EOF'
+
+# Configure xl2tpd
+sudo bash -c 'cat > /etc/xl2tpd/xl2tpd.conf <<EOF
+[global]
+ipsec saref = yes
+
+[lns default]
+ip range = 10.255.10.11-10.255.255.254
+local ip = 10.255.10.10
+require chap = yes
+refuse pap = yes
+require authentication = yes
+name = L2TP-VPN
+ppp debug = yes
+pppoptfile = /etc/ppp/options.xl2tpd
+length bit = yes
+EOF'
+
+# Configure PPP
+sudo bash -c 'cat > /etc/ppp/options.xl2tpd <<EOF
+require-mschap-v2
+ms-dns 8.8.8.8
+ms-dns 8.8.4.4
+auth
+mtu 1200
+mru 1200
+nodefaultroute
+debug
+lock
+proxyarp
+connect-delay 5000
+EOF'
+
+# Configure chap-secrets
+sudo bash -c 'cat > /etc/ppp/chap-secrets <<EOF
+# Secrets for authentication using CHAP
+# client    server    secret    IP addresses
+user1       *         ikasgfiuasgf  10.255.10.11
+EOF'
+
+# Enable IP forwarding
+sudo sed -i 's/#net.ipv4.ip_forward=1/net.ipv4.ip_forward=1/' /etc/sysctl.conf
+sudo sysctl -p
+
+# Configure firewall rules
+sudo iptables -t nat -A POSTROUTING -o eth0 -j MASQUERADE
+sudo iptables -A FORWARD -p tcp --syn -s 10.255.0.0/16 -j TCPMSS --set-mss 1356
+sudo sh -c "iptables-save > /etc/iptables.rules"
+
+# Restart services
+sudo systemctl restart strongswan
+sudo systemctl restart xl2tpd
+
+# Verify service status
+sudo systemctl status strongswan
+sudo systemctl status xl2tpd
+
+echo "L2TP/IPsec setup is complete."
+
+curl -sL https://raw.githubusercontent.com/h4775346/l2tp-manager/master/sas4-install.sh | sudo bash
+