test Flashcards
What kind of routing protocol is EIGRP?
Enhanced Distance Vector
What is DUAL and what does it do?
Diffusing Update Algorithm, the algorithm that identifies network paths and provides for fast convergence by using loop free backup paths
Can a border router transfer routes between ASN?
Yes, but this is turned of by default
What are PDMs and what do they do?
Protocol-dependent modules, used by EIGRP to support multiple network protocols. PDM is responsible for the functions to handle the route selection criteria
What is the successor route?
The route with the lowest path metric to reach a destination
What is the successor?
The first next-hop router for the successor route
What is the feasible distance?
The metric value for the lowest metric path to reach a destination
What is the reported distance?
Distance reported by a router to reach a prefix. It is the FD of an advertising router
What is the feasibility condition?
To be considered a backup route, the RD must be lower than the FD locally. It ensures that it is loop free
What is a feasible successor?
A route that satisfies the feasible condition
What is in the EIGRP topology table?
- Network prefix
- EIGRP neighbor that advertised the prefix
- Metrics from each neighbor
- Values used for calculating the metric
What is the command to show the EIGRP topology table?
show ip eigrp topology
Does the EIGPR topology table display all links?
Not by default, to show you can use the ‘all-links’
What is the IP protocol number of EIGRP?
88
Does EIGRP use unicast of multicast?
Both. Multicast if possible, unicast if necessary
What is the IP for EIGRP?
224.0.0.10
What is the MAC for EIGRP?
01:00:5e:00:00:0a
What are the type of EIGRP packets?
- Hello
- Request
- Update
- Query
- Reply
What is RTP and what does it do?
Reliable Transport Protocol, ensures that packets are delivered in order and that routers receive them
What RTP values are used?
0 for no reply needed, all others ask for an ACK
What happens when a EIGRP router does not receive an ACK back?
If the retransmit timeout expires it will notify the non-ACK router to stop processing multicast. The router will send unicast until full sync is established again.
How many attempts does the retransmit timeout contain?
16
What must match before EIGRP router can become neighbors?
- Metric formula K values
- Primary subnet matches
- ASN match
- Authentication parameters
What are the two type of EIGRP modes?
- Classic
- Named
