S10-Routing Flashcards
Router
Forwards traffic between subnets, internal & external networks, or between 2 external networks.
Do routers separate broadcast domains?
True
How does a router make routing decisions?
Using a Routing table
What is a Routing table?
Function that helps a router determine which route entry is the best fit for the network.
What are the 3 sources of routing information that routers use?
- Directly Connected Route
- Static Route
- Dynamic Route
Directly Connected route
Routing information is learned by physical connections between routers.
How does prefix length correlate with network specificity?
The longer the prefix the more specific the network is.
Static Route
Route that is Manually configured by an admin
What is the Default Static route on a router?
0.0.0.0/0
Dynamic Route
Learned by exchanging information between routers
What 2 techniques are used to prevent routing loops?
- Split Horizon
- Poison Reverse
Split Horizon
Prevents a route learned on one interface from being advertised back out of that same interface
- does not repeat learned routes
Poison Reverse
Causes a route received on one interface to be advertised back out of that same interface with a metric considered to be infinite.
- repeats learned routes but with a very high cost
what are the 2 types of dynamic routing protocols?
- Internal
- External
What is the difference between IGP & EGP?
Interior Gateway Protocols (IGPs) - operate within an autonomous system
Exterior Gateway Protocols (EGPs)
- Operate between autonomous systems
Distance Vector
a type of routing protocol where routers exchange information about their network paths and distances with their neighbors
- Hop Count
- does not consider speed
What is Convergence?
Time it takes for routers to update their routing tables in response to a topology change
What is a converged network?
When all the routers on a network know the same information
What is a Hold-Down Timer?
Method of speeding up convergence times by preventing updates for a specific period of time causing less changes across the network.
T/F More changes across the network speeds up Convergence time
False
What is Hop-count?
Number of routers that are passed through to reach a destination
Link State
routing parameter that’s concerned with the speed/bandwidth of a given link
What are Link-State Routing protocols?
- OSPF
- IF-IF
Which routing protocol has faster convergence times?
Link-State or Distance Vector
Link-State