10 - Advanced Routing Concepts Flashcards
What are the three common characteristics of dynamic routes?
IGP or EGP
classful or classless routing updates
distance-vector or link state routing protocols
What is the collection of all networks managed by a single organization?
Autonomous System
What are IGPs?
routing protocols that dynamically share routing information within an AS
What are EGPs?
routing protocols that dynamically share routing information between multiple ASs
What are the common IGPs in todays networks?
RIP
EIGRP
OSPF
What are the common EGPs in today network?
BGP
What do classful routing protocols do?
- transmit network addresses but not subnet masks
2. automatically summarize networks on their classful bit boundaries
What do classless routing protocols do?
- transmit network addresses and subnet masks
2. enables the use of VLSMs
What happens when ip classless is disabled on a router?
Disables the support of vlsm on classless routing protocols
Is ip classless enabled by default?
yes
What is an example of distance-vector routing protocol?
RIP
What is an example of link-state routing protocol?
OSPF
What is an example of a hybrid routing protocol?
EIGRP
Routers that run distant-vector routing protocol exchange routing updates with ______________?
directly connected neighbors
Routers that use link-state routing protocol flood the network with ___________ packets every time a topology change occurs?
LSA or link state advertisements
What algorithm is used by RIP?
Bellman Ford
What metric is used by RIP?
hop count
What is the hop count limit for RIP?
15
What is the default timer for RIP to send advertisements?
30 seconds
What mechanisms does RIP use to prevent loops?
split horizion
poison reverse
hold-down timers
triggered updates
What is the default time for the hold-down timers?
60 seconds
What version of RIP is classless?
version 2
What version of RIP is classful?
version 1
What is shown in the output of show ip protocols?
How frequently routing updates are sent
which networks are being advertised
whether automatic summarization is enabled
What are the four timers of RIP?
routing updates- every 30 seconds
Invalid- every 180 seconds
hold-down- every 180 seconds
flush-every 240 seconds
How do you modify the timers in RIP?
using the timers basic 30 180 180 240
What are the best practices for modifying the timers in RIP?
the invalid and hold-down timers should be three times the value of the update timer, the flush timer should be greater than the sum of the update timer and the hold down timer
How do you modify the RIP timers for a particular interface?
ip rip advertise
How do you determine the configuration of automatic summarization on a router for RIP?
show ip rip database
can you disable automatic summarization in RIP version 1?
no
How do you disable automatic summarization in RIP version 2?
no auto-summary in RIP router configuration mode
How do you inject a default route into RIP?
default-information originate command
Where do you use the default-information originate command?
only on the router that has been configured with the default route
What is the passive-interface default command used for in RIP?
Is used to prevent interfaces from participating in RIP advertisements. You have to issue the no passive-interface fa0/0 command to allow updates on that interface. You could also just issue the passive-interface fa0/0 command to keep that one interface from participating in RIP
How do you determine a route in the routing table is a rip route?
R preceeds the route in the routing table
What command is used to determine rip is receiving routes?
show ip rip database
