1. Agenda VPN tunnels Configuration of basic core network components Maintenance of Cisco devices Exercises & troubleshooting

2. Abbreviations AP – Access Point AH – Authentication Header AZR – Access Zone Router AGR – Aggregation Router AG – Access Gateway (e.g. Cisco SSG, Juniper ERX) CSA – Central Site Area DHCP – Dynamic Host Configuration Protocol DMVPN - Dynamic Multipoint IPsec Virtual Private Network EIGRP – Enhanced Interior Gateway Routing Protocol ESP– Encapsulating Security Payload GRE – Generic Routing Encapsulation HSA – Hotspot Area IKE – Internet Key Exchange IPSec– Internet Protocol Security NHRP – Next Hop Resolution Protocol OSPF– Open Shortest Path First (Routing Protocol) PPTP– Point-To-Point Tunneling Protocol SSG – Service Selection Gateway VPN – Virtual Private Network

3. AGR - Aggregation Router Interfaces –interface to AGR (there are possibilities to create connection to more then one AGR) - GRE tunnel with IPSec is configured over this link –interface to APS – typically Ethernet. –loopback Routing –The AGR participate in dynamic routing protocol. –The following networks shall be spread out: all networks to AZRs network to AG (SSG) network to management network network to other AGRs if such connection is realized –Default gateway shall be set on SSG in central configuration or on WIP in decentral configuration Multipoint IPsec –AGR may work as a hub in DMVPN (Dynamic Multipoint VPN) configuration

4. AZR - Access Zone Router Interfaces –interface to AGR (there are possibilities to create connection to more then one AGR) - GRE tunnel with IPSec is configured over this link –interface to APs – typically Ethernet. –loopback Routing –The AZR participate in dynamic routing protocol. –The following networks shall be spread out: Network(s) to AGR(s) networks to APs –Default gateway shall be set on AGR or AGRs in case of multiple connections Multipoint IPsec –AZR may work as a spoke in DMVPN (Dynamic Multipoint VPN) configuration

5. DHCP DHCP (Dynamic Host Configuration Protocol) is an open, industry-standard protocol that reduces the complexity of administering networks based on TCP/IP All DHCP messages are carried in User Datagram Protocol (UDP). Datagrams use port 67 at the server and 68 at the client. DHCP Request for an IP Address

6. DHCP Benefits to TCP/IP Network Administrators Simplifies problems associated with manual addressing Centralized administration of IP configuration Dynamic host configuration Seamless IP host configuration Flexibility Scalability

7. Configuring DHCP on Cisco router Enabling the Cisco IOS DHCP Server and Relay Agent Features Router (config)# service dhcp Excluding IP Addresses Router (config)# ip dhcp excluded-address low-address [high-address] Configuring the DHCP Address Pool Name and Entering DHCP Pool Configuration Mode Router (config)# ip dhcp pool name Configuring the DHCP Address Pool Subnet and Mask Router (dhcp-config)# network network-number [mask | /prefix-length] Configuring the Domain Name for the Client Router (dhcp-config)# domain-name domain Configuring the IP Domain Name System Servers for the Client Router (dhcp-config)# dns-server address [address2... address8] Configuring the Default Router for the Client Router (dhcp-config)# default-router address [address2... address8] Configuring the Address Lease Time Router (dhcp-config)# lease {days [hours] [minutes] | infinite}

8. Example of DHCP configuration on Cisco router ip dhcp excluded-address 10.100.1.1 10.100.1.30 ! ip dhcp pool ZONE1 network 10.100.1.0 255.255.255.0 default-router 10.100.1.1 domain-name domain.i250 dns-server 192.168.201.2 ! interface FastEthernet0/1 ip address 10.100.1.1 255.255.255.0

9. DHCP troubleshooting Router# show ip dhcp binding Router# show ip dhcp server statistics Router# show ip dhcp conflict [address] Router# clear ip dhcp binding {address | *} Router# clear ip dhcp conflict {address | *} Router# clear ip dhcp server statistics Router# debug ip dhcp server {events | packets | linkage}

10. Exercise 1.Configure DHCP server on AZR 2.Check if client gets ip address from DHCP server

11. Routing Static Routing –Advantages: Simple to configure and maintain Secure – as only defined routes can be accessed Bandwidth is not used for sending routing updates –Disadvantages Manual update of routes after network changes Explicit addition of routes for all networks Dynamic Routing –EIGRP –OSPF

12. Configuring static routing on Cisco devices ip route Router A ip route 192.168.1.0 255.255.255.0 172.16.1.2 Router B ip route 10.1.1.0 255.255.255.0 172.16.1.1 Router C ip route 10.1.1.0 255.255.255.0 172.16.2.1

13. Exercise 1.Configure static routing on AZR, AGR and SSG 2.Check if client can access (ping) AZR, AGR, SSG

14. Configuring dynamic routing on Cisco devices - EIGRP Router A router eigrp 1 network 172.16.1.0 0.0.0.3 network 172.16.2.0 0.0.0.3 network 10.1.1.0 0.0.0.255 no auto-summary Router B router eigrp 1 network 172.16.1.0 0.0.0.3 network 10.1.1.0 0.0.0.255 no auto-summary Router C router eigrp 1 network 172.16.2.0 0.0.0.3 network 10.1.1.0 0.0.0.255 no auto-summary

15. Configuring dynamic routing on Cisco devices - OSPF Router A router ospf 10 network 172.16.1.0 0.0.0.3 area 0 network 172.16.2.0 0.0.0.3 area 0 network 10.1.1.0 0.0.0.255 area 0 Router B router ospf 100 network 172.16.1.0 0.0.0.3 area 0 network 10.1.1.0 0.0.0.255 area 0 Router C router ospf 1 network 172.16.2.0 0.0.0.3 area 0 network 10.1.1.0 0.0.0.255 area 0

16. Exercise 1.Configure dynamic routing (EIGRP) on AZR, AGR and SSG 2.Check if client can access (ping) AZR, AGR, SSG 3.Configure dynamic routing (OSPF) on AZR, AGR and SSG 4.Check if client can access (ping) AZR, AGR, SSG

17. VPN Virtual Private Network GRE - Generic Routing Encapsulation PPTP- Point-to-Point Tunneling Protocol

18. Types of VPNs Secure VPNs - Secure VPN protocols include the following: -IPsec -SSL -PPTP -L2TP -L2TPv3 Trusted VPNs - MPLS - L2F

19. IPSec Functions data confidentiality (encryption) data integrity (verification) origin authentication (authentication the source of the packet) Verification that each packet is unique (not duplicated)

20. Type of Encryption symmetric –DES –3DES –HMAC-Message Digest 5 (MD5) –HMAC-SHA asymmetric –Rivest, Shamir, and Adelman (RSA) Type of Authentication Pre-shared keys RSA signatures RSA encrypted nonces

21. IPSec Protocols

22. IPSec Modes

23. VPN (DMVPN) GRE/IPsec

24. Standards (Cisco IOS IPSec) IPSec (RFCs 2401-2410) IPSec Encapsulating Security Payload (ESP) Using DES/3DES (RFC 2406) IPSec Authentication Header (AH) using MD5 or SHA (RFCs 2403-2404) Internet Key Exchange (IKE) (RFCs 2407-2409)

25. IPsec/GRE Example (basic) Phase I (IKE Policy) Internet Fa0/1 192.168.6.2 Tunnel 192.168.10.0/30 AZR AGR Fa0/0 192.168.5.1 tunnel 10 192.168.10.2/30 tunnel 10 192.168.10.1/30 crypto isakmp policy 1 authentication pre-share hash md5 encryption 3des crypto isakmp key Cisco123 address 192.168.5.1 crypto isakmp policy 1 authentication pre-share hash md5 encryption 3des crypto isakmp key Cisco123 address 192.168.6.2

26. IPsec/GRE Example (basic) Phase II (IPsec Policy) Internet Fa0/1 192.168.6.2 Tunnel 192.168.10.0/30 AZR AGR Fa0/0 192.168.5.1 tunnel 10 192.168.10.2/30 tunnel 10 192.168.10.1/30 crypto ipsec transform-set name1 esp-3des esp-md5-hmac mode transport access-list 110 permit gre host 192.168.6.2 host 192.168.5.1 crypto ipsec transform-set name1 esp-3des esp-md5-hmac mode transport access-list 110 permit gre host 192.168.5.1 host 192.168.6.2

27. IPsec/GRE Example (basic) Phase II (IPsec Policy) Internet Fa0/1 192.168.6.2 Tunnel 192.168.10.0/30 AZR AGR Fa0/0 192.168.5.1 tunnel 10 192.168.10.2/30 tunnel 10 192.168.10.1/30 crypto map map1 local-address FastEthernet0/1 crypto map map1 10 IPsec-isakmp set peer 192.168.5.1 match address 110 set transform-set name1 crypto map map1 local-address FastEthernet0/0 crypto map map1 10 IPsec-isakmp set peer 192.168.6.2 match address 110 set transform-set name1

28. IPsec/GRE Example (basic) Phase III (tunnel) Internet Fa0/1 192.168.6.2 Tunnel 192.168.10.0/30 AZR AGR Fa0/0 192.168.5.1 tunnel 10 192.168.10.2/30 tunnel 10 192.168.10.1/30 interface tunnel 10 ip address 192.168.10.2 255.255.255.252 tunnel source FastEthernet0/1 tunnel destination 192.168.5.1 ip mtu 1440 crypto map map1 interface Fastethernet0/1 ip address 192.168.6.2 255.255.255.0 crypto map map1 router eigrp 1 network 192.168.10.0 0.0.0.3 no auto-summary interface tunnel 10 ip address 192.168.10.1 255.255.255.252 tunnel source FastEthernet0/0 tunnel destination 192.168.6.2 ip mtu 1440 crypto map map1 interface Fastethernet0/0 ip address 192.168.5.1 255.255.255.0 crypto map map1 router eigrp 1 network 192.168.10.0 0.0.0.3 no auto-summary

29. Exercise 1.Configure static IPSec/GRE tunnel between AZR and AGR 2.Check if wired client can access (ping) AGR, SSG via VPN tunnel

30. IPsec/GRE Example (DMVPN) Phase I (IKE Policy) Internet Fa0/1 192.168.6.2 Tunnel 192.168.10.0/30 AZR (spoken) AGR (hub) Fa0/0 192.168.5.1 tunnel 0 192.168.10.2/24 tunnel 0 192.168.10.1/24 crypto isakmp policy 1 authentication pre-share hash md5 encryption 3des crypto isakmp key Cisco123 address 0.0.0.0 0.0.0.0 crypto isakmp policy 1 authentication pre-share hash md5 encryption 3des crypto isakmp key Cisco123 address 0.0.0.0 0.0.0.0

31. IPsec/GRE Example (DMVPN) Phase II (IPsec Policy) Internet Fa0/1 192.168.6.2 Tunnel 192.168.10.0/30 AZR (spoken) AGR (hub) Fa0/0 192.168.5.1 tunnel 0 192.168.10.2/24 tunnel 0 192.168.10.1/24 crypto ipsec transform-set name1 esp-3des esp-md5-hmac mode transport crypto ipsec profile bwsvpnprofile1 set transform-set name1 crypto ipsec transform-set name1 esp-3des esp-md5-hmac mode transport crypto ipsec profile bwsvpnprofile1 set transform-set name1

32. IPsec/GRE Example (DMVPN) Phase III (tunnel) Internet Fa0/1 192.168.6.2 Tunnel 192.168.10.0/30 AZR (spoken) AGR (hub) Fa0/0 192.168.5.1 tunnel 0 192.168.10.2/24 tunnel 0 192.168.10.1/24 interface tunnel 0 ip address 192.168.10.2 255.255.255.0 ip mtu 1400 ip nhrp authentication ciscokey ip nhrp map 192.168.10.1 192.168.5.1 ip nhrp network-id 1 ip nhrp holdtime 300 ip nhrp nhs 192.168.10.1 tunnel source FastEthernet0/1 tunnel destination 192.168.5.1 tunnel key 0 tunnel protection ipsec profile bwsvpnprofile1 interface tunnel 0 ip address 192.168.10.1 255.255.255.0 ip mtu 1400 ip nhrp authentication Cisco123key ip nhrp map multicast dynamic ip nhrp network-id 1 ip nhrp holdtime 600 no ip split-horizon eigrp 1 tunnel source FastEthernet0/0 tunnel mode gre multipoint tunnel key 0 tunnel protection ipsec profile bwsvpnprofile1

33. IPsec/GRE Example (DMVPN) Phase III (interfaces) Internet Fa0/1 192.168.6.2 Tunnel 192.168.10.0/30 AZR (spoken) AGR (hub) Fa0/0 192.168.5.1 tunnel 0 192.168.10.2/24 tunnel 0 192.168.10.1/24 interface FastEthernet0/0 ip address 192.168.5.1 255.255.255.0 router eigrp 1 network 192.168.10.0 0.0.0.255 no auto-summary interface FastEthernet0/1 ip address 192.168.6.2 255.255.255.0 router eigrp 1 network 192.168.10.0 0.0.0.255 no auto-summary

34. IPsec/GRE troubleshooting Router# show ip nhrp Router# show ip interface Router# show crypto isakmp sa Router# show crypto ipsec sa Router# show crypto ipsec sa detail Router# show crypto map Router# show crypto engine connection active Router# show ip route Router# debug crypto isakmp Router# debug crypto ipsec Router# debug crypto engine

35. Exercise 1.Configure dynamic IPSec/GRE tunnel (DMVPN) between AZR and AGR 2.Check if wired client can access (ping) AGR, SSG via VPN tunnel

36. MTU configuration on interface Router (config)# access-list 101 permit udp any any Router (config)# route-map clear-df permit 10 Router (config-route-map)# much ip address 101 Router (config-route-map)# set ip df 0 Router (config-route-map)# end Router (config)# interface FastEthernet0/0 Router (config-if)# ip address 192.168.10.1 255.255.255.0 Router (config-if)# ip policy route-map clear-df Router (config-if)# ip mtu 1400 Router (config-if)# end

37. Maintenance of Cisco devices Copying the Configuration to a TFTP Server Router# copy run tftp Address or name of remote host []?192.168.1.1 Destination filename [router-confg] ?run-confg !! 486 bytes copied in 12.2 secs (40 bytes/sec) Router# Restoring the Configuration from TFTP Server Router# copy tftp run Address or name of remote host []?192.168.1.1 Source filename []?run-confg Destination filename [running-config]?[Enter] Accessing tftp://192.168.1.1/run-confg... Loading run-confg from 192.168.1.1 (via FastEthernet0/1): !! [OK - 486/4096 bytes] 486 bytes copied in 5.3 secs (99 bytes/sec) Router#

38. Exercises & troubleshooting 1.Design and connect your own network 2.Configure DHCP Server on AZR 3.Configure AZR, AGR, routing and VPN tunnel between AZR and AGR 4.Configure Cisco Access Point 5.Test your configuration This exercise assumes that SSG and WI@ was correctly configured before.