WAN Technologies Flashcards
What speed is a T1 line
1.544 mbps
What speed is an E1 line
2.048 mbps
What are the two WAN encapsulation methods
HLDC and PPP
What are the features of HLDC
- no features other connectivity
- nothing to unpack
- proprietary and default encapsulation method
What are the features of PPP
- Industry standard
- Can connect non cisco devices
- Lots of features e.g compression, multilink, callback, authentication
What are the 3 layers of PPP
NCP (network control protocol) - responsible for L3 protocols
LCP link control protocol - negotiates features
HLDC
What authentication does PPP use
PAP or CHAP (more secure, uses hashing)
What are the 4 realms of PPP
Multilink
Callback
Authentication
Compression
What does the debug ppp authentication command allow
To watch PPP autentication as it happens
What is multilink
Allows the bundling of serial interfaces to double BW
What are the differences between Leased lines and packet switched networks
Leased lines:
Inflexible
unsued BW
Expensive
Packet switched:
Virtual circuits
Each packet is destinationed
Cheaper
What are the types of switched networks
x.25
frame relay
ATM
MPLS
How does MPLS work
Allows to put tags on the connection
How does PPPoE work
PPP over ethernet
Using a dialer interface
How is PPPoE configured
interface Dialer1 R1(config-if)# ip address negotiated R1(config-if)# encapsulation ppp R1(config-if)# dialer pool 1 R1(config-if)# end
R1(config)# interface Ethernet0/1
R1(config-if)# no ip address
R1(config-if)# pppoe-client dial-pool-number 1
What are the VPN objectives
- Confidentiality – stop prying eyes
- Authentication – validate the identity
- Data integrity – preventing change (hashing)
- Anti replay – eliminate déjà vu
What are the types of VPN you can have
- Site to site
- Client (remote access – ipsec)
- SSLVPN (https)
- DMVPN (dynamic multipoint)
What is a GRE tunnel
Encapsulation tunnelling protocol
Allows routing info to pass between connected networks
What is a DMVPN
Dynamic multipoint VPN
Makes it easier to configure several vpns
A little more automated and easier to manage
How is a GRE tunnel configured
- Interface tunnel #
- Ip address
- Tunnel mode gre ip (tunnel mode gre multipoint is for dmvpn)
- Tunnel source
- Tunnel destination
What port does BGP use
TCP 179
How is BGP configured
• Router bgp 5000
• Neighbour 200.1.1.2 remote-as 2500
• Network 63.1.5.0 mask 255.255.255.0
*Network command takes a route from internal routing table and advertises to outside world *
