VPN

VPN

1. Security feature of VPN
   1. Confidentiality (privacy): Preventing anyone in the middle of the internet (man in the middle) from being ale to read the data
   2. Authentication: Verifying that the sender of the VPN packet is a lefitimate device and mot a device used by an attacker.
   3. Data integrity: Verifying that the packert was not changed as the packet transited the internet.
   4. Anti–replay: Preventing a man in the middle from copying and later replaying the packets sent by a legitimate user, for the purpose of appearing to ba legitimate user.
2. Steps of VPN
   1. Gre Config
      1. Router 1
         1. Int ser0/0/0
            1. Ip address 1.1.1.1 255.255.255.0
         2. Int tunnel0
            1. Ip address 10.1.3.1 255.255.255.0
            2. Tunnel mode gre ip
            3. Tunnel source serial 0/0/0
            4. Tunnel destination 2.2.2.2
         3. Router ospf 1
            1. Network 10.0.0.0 255.255.255.0 area 0
      2. Router 2
         1. Int ser0/0/0
            1. Ip address 2.2.2.2 255.255.255.0
         2. Int tunnel1
            1. Ip address 10.1.3.2 255.255.255.0
            2. Tunnel mode gre ip
            3. Tunnel source serial 0/0/0
            4. Tunnel destination 1.1.1.1
         3. Router ospf 1
            1. Network 10.0.0.0 255.255.255.0 area 0
      3. Show ip interface brief
      4. Show ip interfae tunnel0
         1. Interface up/down
         2. Ip
         3. Dunnel ip , interface, destination, protocol
      5. Show ip route 10.0.0.0
      6. ACL
         1. Ip access-list extended inbound-from-Internet
            1. Permit tcp
            2. Permit udp
            3. Permit gre any any
            4. Interface s0/0/0
               1. Ip address-group inbound-from-Internet in
   2. PPPOE
      1. PPPOE config
         1. Interface dialer 2
            1. ! Layer 3 details next
            2. Ip address negotiated
            3. Mtu 1492
            4. ! Layer 2 details next
            5. Encapsulation ppp
            6. Ppp chap hostname Fred
            7. Ppp chapp password Barney
            8. ! Layer 1 details next
            9. Dialer pool 1
            10. @ Physical interface – the one connected towrd the ISP
         2. Interface G0/1
            1. No ip address
            2. Pppoe-client dial-pool-number 1
            3. Ppppoe enable
            4. Mac-address xxxxxx ! Optional
            5. No shutdown
      2. PPPOE verification
         1. Show interface dialer 2
            1. Outpput interface and binded interface status
            2. Interface is bound to Vi2
            3. Encapsulation ppp, lcp open
            4. PPPoE vaccess, cloned by Dialer2
            5. Interface is bound to Di2 (encapsulation ppp)
         2. Show interface virtual-access 2
         3. Show interface virtual-access 2 configuration
            1. IOS generated configruation
         4. Show pppoe session interface x
            1. Show interfaces involved in making of PPPoE
            2. Show pppoe session
            3. Show ip rouote
            4. Show ip inter brief dialer 2
               1. Method ipcp