1. DrayTek VPN Solution

2. Outline What is VPN What does VPN Do Supported VPN Protocol How Many Tunnels does Vigor Support VPN Application Special VPN Application CVM (Central VPN Management) Trouble Shooting

3. What is VPN A virtual private network (VPN) extends a private network across a public network, such as the Internet. It enables a computer to send and receive data across shared or public networks as if it were directly connected to the private network, while benefiting from the functionality, security and management policies of the private network. http://en.wikipedia.org/wiki/Virtual_private_network

4. What is VPN

5. What does VPN Do Host to LAN allow employees to securely access their company's intranet while traveling outside the office. Similarly, VPNs securely and cost-effectively connect geographically disparate offices of an organization, creating one cohesive virtual network. We call it as LAN to LAN. http://en.wikipedia.org/wiki/Virtual_private_network

6. Supported VPN Protocol PPTP (TCP 1723) L2TP (UDP 1701) IPsec (UDP 500) L2TP over IPsec SSL VPN (TCP 443) mOTP

7. How Many VPN Tunnel does Vigor Support Vigor Model IPsec/PPTP/L2TPSSL Vigor21102N/A Vigor21302N/A Vigor291216N/A Vigor292032N/A Vigor292525 Vigor293010030 Vigor295020010 Vigor296020020 Vigor3200 Series6410 Vigor3300 Series200NA Vigor3900500 (PPTP/L2TP 200)20

8. How Many VPN Tunnel does Vigor Support Vigor ModelIPsec/PPTP/L2TPSSL Vigor27102N/A Vigor27602N/A Vigor28303210 Vigor28503210 Vigor28603210

9. VPN Application LAN to LAN Host to LAN – PPTP/L2TP/IPsec/L2TP over IPsec – SSL VPN – mOTP VPN Trunk

10. LAN to LAN 172.17.1.0/24 192.168.1.0/24

14. Host to LAN Client site OS could be – Windows (may use Smart VPN client) – Mac OS/iOS – Android – Ubuntu

16. SSL VPN SSL Tunnel – TCP port 443 SSL Application SSL Proxy http://www.draytek.com.tw/index.php?option=com_k2&view=itemlist&task=category&id=129:ssl- vpn&Itemid=293&lang=en

17. SSL VPN

19. mOTP: Mobile One Time Password

21. VPN Trunk-Load Balance

22. VPN Trunk-Backup

25. Special VPN Application Change default route to this VPN tunnel Apply VPN Tunnel as Interface for L/B Policy VPN backup when specified WAN drops Packets trigger to establish the VPN tunnel Add more network into Phase 2 SA

26. Change Default Route to VPN tunnel Enable VPN default route Go via VPN tunnel for local service

27. Apply VPN Tunnel as Interface for L/B Policy How to Use Load-Balance/Route Policy http://www.draytek.com.tw/index.php?option=com_k2&view=item&id=5181&Itemid=293&lang=en

28. VPN Backup when Specified WAN Down

29. Add More Network into Phase2 SA

30. CVM

31. How to Use Central VPN Management http://www.draytek.com.tw/index.php?option=com_k2&view=item&id=5293&Itemid=293&lang=en

32. Trouble Shooting VPN is up but Traffic cannot pass to remote network?

33. What to Do? Check Routing Table Use ping to diagnose Use trace route to diagnose Check Firewall Rule

34. Check Routing Table Check Dial-Out Vigor's Routing table Check Dial-In Vigor's Routing table – If the route to remote VPN network doesn't exist, check TCP/IP Network Setting in VPN LAN to LAN profile. – If the route to remote VPN network exists, check if the host can respond ping.

35. PPTP Dial Out

36. PPTP Dial In

37. IPsec Dial Out

38. IPsec Dial In

39. Use Ping to Diagnose Ping to host from its Local Router – If Local Router cannot get ping response from the host, check the firewall setting on the host. Find a host that can respond ping from its Local Router, and then ping the host from Remote Router.

40. Ping Diagnostic

41. Check ARP Table

42. Use Trace Route to Diagnose Use command “tracert -d destination IP” to check if the packet is sending through the right gateway.

43. Check Firewall Rule Check Firewall Rule and see if the packet to remote VPN network is blocked by firewall rule.

44. Case Study

45. Router A has two networks connected, which are 192.168.1.0/24 and 192.168.2.0/24. Router B has one network connected, which is 192.168.139.0/24. Computer with IP 192.168.139.10 can ping IP 192.168.1.10, but cannot ping IP 192.168.2.10. What could we do?

46. Use Trace Route on Computer with IP 192.168.139.10 to destination IP 192.168.2.10. Result: The packet is routed to the Internet?! Step1:

47. Check Router B's Routing Table. Result: There is no Route to 192.168.2.0/24 on Router B. Next Step:

48. Add Route 192.168.2.0/24 via More option in VPN LAN to LAN Profile. Then disconnect and reconnect VPN. Result: Router B has route to network 192.168.2.0/24 now. Next Step:

50. Use Trace Route on Computer with IP 192.168.139.10 to destination IP 192.168.2.10 again. Result: The packet is stopped at IP 192.168.1.1. Next Step:

51. Next Step Check Routing Table on Router A with IP 192.168.1.1. Result: Route A has Static Route – to destination 192.168.2.0/24 via 192.168.1.15.

52. Try to ping IP 192.168.1.15 from Router A. Result: No ping response from IP 192.168.1.15 Next Step:

53. Check Router A's ARP Table. Result: There is no ARP for IP 192.168.1.15. It seems the host isn't connected to Router A! Next Step:

54. Check the Router setting that is connected between Router A and network 192.168.2.0/24. Result: The correct IP is 192.168.1.13! Next Step:

55. Correct the Static Route setting from Router A then use Trace Route on Computer with IP 192.168.139.10 to destination IP 192.168.2.10 again. Result: It succeeds! Next Step:

56. Application Note When VPN tunnel is established, why can't I access any host in the remote subnet ? -http://www.draytek.com.tw/index.php?option=com_k2&view=item&id=1279&Itemid=293&lang=enhttp://www.draytek.com.tw/index.php?option=com_k2&view=item&id=1279&Itemid=293&lang=en