WANs Flashcards
Is a WAN a public or private link?
WANs can be private links via leased lines.
Common types of VPN protocols for site to site connections? (x4)
- IPsec - Open standard. Doesnt support Multicast which is used by routers to share routes
- GRE (Generic Routing Encapsulation) over IPsec - adds support for multicast
- IPsec VTI (Virtual Tunnel Interface) - Cisco proprietary simplified configuration, supports multicast.
- DMVPN (Dynamic Multipoint VPN) - Cisco proprietary. Enables full mesh connectivity between all offices although the config steps act like configuring a hub and spoke VPN model.
Common type of VPN encryption for end-user to site connections?
SSL but sometimes also IPsec
Primary WAN connectivity options?
- Leased Line
- MPLS
- Satellite
Secondary WAN connectivity options?
(can be primary options for small offices)
- DSL
- Cable Modem
- Wireless 4G or LTE
What will a SLA include?
- Uptime
- Loss
- Delay
- Maybe Jitter
What is a Leased Line to Cisco?
A point-to-point connection using a serial port.
What is PPP?
Point-to-Point Protocol
What is HDLC?
cHDLC?
Protocol used over serial connections
cHDLC is the Cisco proprietary version of HDLC
What OSI layer is HDLC
Layer 2
What OSI layer is PPP for leased line serial connections?
Layer 2
What side of a link is the clock rate set?
DCE or DTE
DCE.
on the Data Communications Equipment (providor),
not on the DTE - Date Termination Equipment (customer)
Difference between serial Clock Rate and Interface Bandwidth setting?
The bandwidth statement doesn’t affect the physical clocking of the line. The bandwidth statement only effects software policies such as routing protocol metrics and QoS shaping.
Default bandwidth of a serial interface?
1.544 Mbps (T1)
HDLC confg steps:
PPP config steps:
Command to view PPP settings:
R1# show ppp all
What is the default username for CHAP in one-way PPP authentication
The remote device’s hostname
Command to configure CHAP authentication
R1(config-if)# ppp chap password Presto1
What is MLPPP
MultiLink PPP - Using multiple parallel serial links as one single logical link.
MLPPP Config steps:
Define PPPoE
Point-to-Point Protocol over Ethernet
Would you configure PPPoE on the router or the DSL model?
Either are standard things that are done.
PPPoE Config steps:
What is a ‘Virtual Access’ interface on a Router?
A product of a PPPoE dialer configured on the router.
Define GRE
Generic Routing Encapsulation
Does not support encryption but does support multicast for routing protocol traffic.
Can be paired with IPsec for a full end to end tunnel.
GRE Tunnell config steps:
