15 - Private WANs with Internet VPN Flashcards
What device do Telcos use to split out Internet traffic from analog voice?
DSLAM
What features or Goals can an Internet VPN provide?
- Confidentiality
- Authentication
- Data Integrity
- Anti-replay
What is IPSEC?
An architecture or framework for Security Services for IP Networks. It defines how two Internet-connected devices can achieve the goals of a VPN.
What does GRE stand for?
Generic Routing Encapsulation
In GRE what is the delivery header?
Uses IP addresses from the Unsecured Network to allow routers to route the packet over the Internet
What are the commands to build a GRE tunnel on router1?
- int s0/1
- ip address 1.1.1.1 255.255.255.0
- exit
- int tun0
- ip address 10.1.3.1 255.255.255.0
- tunnel mode gre ip
- tunnel source s0/1
- tunnel destination 2.2.2.2
What are the commands to build a GRE tunnel on router2?
- int s1/1
- ip address 2.2.2.2 255.255.255.0
- exit
- int tun0
- ip address 10.1.3.2 255.255.255.0
- tunnel mode gre ip
- tunnel source s1/1
- tunnel destination 1.1.1.1
Will a router filter an outbound VPN tunnel?
No, routers don’t filter packets that are created locally on the router. They will however filter an inbound packet.
What are the commands necessary to build a GRE tunnel?
- public IP on the outside interface
- create tunnel interface
- private IP addresss
- tunnel mode gre ip
- tunnel source (public IP address on the outside interface)
- tunnel destination (remote public IP address)
Will a VPN tunnel get built if the local router doesn’t have a route to the remote router public IP?
No.
What would an ACL need to say to permit GRE?
permit gre any any
What protocol and port does GRE use?
IP 47
What is an NHRP server
server process on a DMVPN Hub router that provides tunnel IP and public IP address info of any other DMVPN router thus allowing router R2 to build a VPN tunnel to R3
What is PPPoE?
PPP over Ethernet
For PPPoE, what 6 commands are needed on the dialer interface?
- ip address negotiated
- mtu 1492
- encap ppp
- ppp chap hostname fred
- ppp chap password barney
- dialer pool 1
For PPPoE, what 2 commands are needed on the physical interface?
* no ip address * ppp-client dial-pool-number 1
For PPPoE, what command on the physical interface is auto-generated?
pppoe enable
For PPPoE Verification what is the PPPoE Session:
IOS generated session that acts to implement PPP and PPPoE specifics such as session logic, status from IPCPs, sends and receives PPPoE messages to/from the ISP
For PPPoE Verification what is the Virtual Access Interface?
If PPPoE reaches the desired ‘UP’ state, a Virtual Access Interface is created that Binds itself with the Dialer interface and Physical interface.
What are 2 ‘show’ commands to verify the PPPoE configuration
* show interfaces dialer 2 * show interfaces virtual-access 2 config
What is the ‘show’ command to check the PPPoE session status?
* show pppoe session interface gig0/1
What ‘show’ command verifies L3 status?
* show ip route
When troubleshooting PPPoE what is a good approach?
Layer 1 first, layer 2, then layer 3
What should ‘show interfaces dialer2’ show?
up/up(spoofing)
