Use LEFT and RIGHT arrow keys to navigate between flashcards;
Use UP and DOWN arrow keys to flip the card;
H to show hint;
A reads text to speech;
30 Cards in this Set
- Front
- Back
Why does Cisco add a Type field to HLDC headers? |
To allow it to transport IPv6 packets |
|
What is the default data link protocol on serial interfaces? |
HLDC |
|
What is the main alternative to HLDC? |
PPP |
|
Does PPP support asynchronous links? |
Yes |
|
What 2 authentication protocols does PPP support? |
Password Authentication Protocol (PAP) and Challenge Handshake Authentication Protocol (CHAP) |
|
What 2 types of control protocols does PPP use? |
Link Control Protocol (LCP) and Network Control Protocols (NCP) |
|
How many instances of LCP does PPP use? |
1 |
|
How many instances of NCP does PPP use? |
1 per Layer 3 protocol on interface |
|
What is the primary difference between PAP and CHAP? |
CHAP hashes the password instead of sending it in cleartext |
|
What 2 pieces of information does CHAP use to create the hash? |
The password and a shared number (sent in original challenge) |
|
What command needs to be run to set PPP on a serial link? |
"Encapsulation ppp" on both interfaces on link |
|
What command will show that HLDC or PPP encapsulation is set on an interface? |
Show interfaces |
|
Does a router require a host name for CHAP? Why or why not? |
Yes- it is the used as the username for the neighboring router |
|
What command sets CHAP authentication for PPP? |
ppp authentication chap |
|
What command will configure CHAP username/password for PPP? |
username <hostname> password <shared_password> |
|
Does the password for CHAP need to be identical between neighbors? |
Yes |
|
What command will show the details of PPP configuration? |
show ppp all |
|
What does multilink PPP do? |
Treats multiple parallel serial links as a single L3 link |
|
How does multilink PPP handle load balancing? |
It breaks a frame into multiple smaller frames (I per channel) |
|
What command is used to create a multilink interface? |
Interface multilink <#> |
|
Does a multilink interface number need to be the same on both ends of a link? |
Yes |
|
What command is used to add an interface to a multilink interface? |
Ppp multilink group <#> |
|
What 2 interfaces must "ppp multilink group <#>" be run on to link a physical interface to a multilink interface? |
The physical interface and the multilink interface |
|
For a multilink interface, should L3 commands (ip address, etc.) be run on the physical or multilink interface? |
Multilink interface |
|
What is the likely problem for WAN encapsulation if the line is up on both ends, but the protocol is flapping? |
Mismatched encapsulation |
|
What line/protocol status likely indicates an encapsulation mismatch on WAN encapsulation? |
Line up on both ends, but protocol flapping |
|
What WAN encapsulation problem will lead to the line showing as up, but the protocol down at one end? |
Keepalive disabled on the end where protocol is up |
|
What will line/protocol show if the keepalive is disabled on one end of an HLDC tunnel? |
The line will be us, but protocol will be down on the line with the keepalive set |
|
What WAN encapsulation problem will cause the line to show as up, but protocol as down on both ends? |
failed PAP/CHAP authentication |
|
What will the line/protocol status be if PAP/CHAP authentication fails on a PPP tunnel? |
Line up, protocol down on both ends |