CCNA 1 Flashcards
Command to configure IPv6 static default route
Ipv6 route ::/0 interface next-hop
Command to show IPv6 access lists on a router?
Show ipv6 access-list
Command to allow telnet and ssh
Transport input telnet ssh
AAA stands for?
Authentication, authorization and accounting.
What is an API?
A contract that describes how various components communicate and exchange data with each other.
FTP port numbers
20, 21.
How to open debug for nat?
Debug ip nat
What is LLDP?
Link layer discovery protocol
Finds device neighbors.
What is CDP?
Cisco discovery protocol.
Finds device neighbors.
(Doesn’t work with PCs)
What is MSTP?
Multiple spanning tree protocol.
Combines best of PVST & 802.1Q.
Uses 1 root for many vlans.
Speed: fast
Resources: med or high
Trees: one for multiple vlans
802.1s
What is STP?
Spanning tree protocol
Used for vlans.
Ports take ~50sec to boot.
Speed: slow
Resources: low
Trees: one
802.1d
Steps:
- Determine root bridge (by priority, then mac)
- Determine root port.
What does “error-disables” mean?
The port is down.
What is a BPDU?
Bridge protocol data unit
What does BPDU Guard do?
Protects spanning tree.
- disables a port (usually a Port Fast one) if it receives a BPDU.
(BPDUs come from switches)
What is DSCP?
Differentiated Services Code Point (DSCP) is a means of classifying and managing network traffic and of providing quality of service (QoS) in modern Layer 3 IP networks. It uses the 6-bit Differentiated Services (DS) field in the IP header for the purpose of packet classification.
(As opposed to 3-bit with COS)