Day 19 - Basic Routing Concepts Flashcards
The results in a routing table result in 3 types of path determination. What are they?
Directly connected network
Remote networks
No route determined
If a packet is being forwarded out a fastEthernet interface then the packet is encapsulated in what type of frame?
Ethernet frame
If the exit interface for a packet is a serial interface what type of frame is the IP packet encapsulated in?
PPP Frame
When a router is making a determination on where to send traffic in with a routing table, the preferred route is the route with the longest what?
Longest prefix match
Do serial interfaces use MAC addresses?
No
What data-link address do interfaces using High-Level Data Link Control (HDLC) use?
0x8F
When an Ethernet frame contains an IP packet in the data portion of the frame, which Ethertype field is used?
0x800
A router can learn routes from 3 sources. What are they?
Directly connected routes
Static routes
Dynamic routes
True or False:
Dynamic routing is more secure than static routing
False
Which type of routing (Dynamic or Static) uses more memory, CPU usage and link bandwidth?
Dynamic
Which type of routing (Dynamic or Static) always uses the same route to the desination?
Static
Which type of routing (Dynamic or Static) uses a route that depends on the current topology?
Dynamic
What are the 10 IGPs?
RIP
RIPv2
RIPng
IGRP
EIGRP
EIGRP for IPv6
OSPFv2
OSPFv3
IS-IS
IS-IS for IPv6
What are the 6 distance vector routing protocols?
RIP
RIPv2
RIPng
IGRP
EIGRP
EIGRP for IPv6
What are 4 link state routing protocols?
OSPFv2
OSPFv3
IS-IS
IS-IS for IPv6
What are the 3 EGPs?
EGP
BGPv4
MP BGP-4 (IPv6)
What type of gateway protocol are the EGPs?
Path vector
Routing protocols are classified into different groups according what characteristics?
IGP or EGP
Distance vector or link state
Classful or classless
This is a collection of routers under a common administration that presents a common, clearly defined routing policy to the Internet
Autonomous System (AS)
This group of routing protocols is used for intra-AS routing
IGPs
This group of routing protocols is used for inter-AS routing
EGPs
Distance vector protocols typically use what algorithm?
Bellman-Ford
Distance, in regards to distance vector protocols, is defined in terms of what?
Metric such as hop count
Direction, next hop router
In distance vector routing protocols, the router knows only the routing information received from its what?
Neighbors
True or False:
Distance vector protocols have a full map of the entire topology of the network
False
What type of overarching group of routing protocols works best for flat networks who don’t require hierarchical design, hub and spoke networks, and convergence times are a non-factor
Distance vector protocols
True or False:
A router configured with a link state routing protocol can create a complete view, or topology, of the network by gathering information from all of the other routers
True
A router configured with this type of routing protocol can create a complete view, or topology, of the network by gathering information from all of the other routers
Link state routing protocol
__________ __________ __________ do not send subnet mask information in routing updates
Classful routing protocols
What routing protocol is considered a classful routing protocol?
RIPv1 and IGRP
__________ ___________ __________ include the subnet mask with the network address in routing updates
Classless routing protocols
What routing protocols are considered classless routing protocols?
RIPv2
EIGRP
OSPF
IS-IS
BGP
What routing protocol uses hop count as its metric?
RIP
What routing protocol uses bandwidth, delay, reliability and load and its metric? By default only bandwidth and delay are used.
IGRP and EIGRP
What routing protocol uses cost as its metric?
OSPF and IS-IS
If you want to view the metric associated with a certain routing protocol what command can you use to view that?
show ip route
All routing protocols are capable of automatically load balancing traffic for up to how many equal cost routes?
4
The administrative distance value ranges from _____ to _____
0 - 255
The __________ the AD value, the more preferred the route
Lower
What is the most preferred AD?
0 for a connected route
What does an AD of 255 mean?
Means the router will not believe the source of that route and it will not be installed in the routing table
What command other than show ip route can give you information about the AD values?
show ip protocols
What is the default AD of a connected route?
0
What is the default AD of a static route?
1
What is the default AD of an EIGRP summary route?
5
What is the default AD of an external BGP route?
20
What is the default AD of an internal EIGRP route?
90
What is the default AD of an IGRP route?
100
What is the default AD of an OSPF route?
110
What is the default AD of an IS-IS route?
115
What is the default AD of a RIP route?
120
What is the default AD of an external EIGRP route?
170
What is the default AD of an internal BGP route?
200
What multicast address are RIP updates sent to?
224.0.0.9
What multicast address are OSPF updates sent to?
224.0.0.5 and 224.0.0.6
What multicast address are EIGRP updates sent to?
224.0.0.10
After how many hops is a route considered unreachable via RIP
16
When is a route considered unreachable via OSPF
Depends on the MaxAge of LSA which is never incremented past 3600 seconds
Do OSPF and EIGRP send periodic updates?
No. RIP does that
Name the metrics for RIP, EIGRP and OSPF
RIP - Hop Count
EIGRP - Bandwidth and Delay
OSPF - Bandwidth
A _________ field avoids a situation in which an undeliverable packet circulates endlessly on the network
TTL
Solve for definition:
A routing table is sent immediately in response to a routing change
Triggered updates
OSPF Routers use what kind of database to calculate the current best routes to each subnet
LSDB
Routing updates via OSPF are advertised as what type of messages?
Link state advertisements (LSAs)
Link state protocols require periodic reflooding of the LSAs every __ __________ by default
30 minutes
If a LSA changes, router does what?
Immediately floods the changed LSA
What algorithm does OSPF use?
Dijsktra method
When an LSA changes, link state protocols react swiftly, using the current best routes as quickly as possible. This is known as what?
Convergence
What routing protocol has the lowest administrative distance?
IS-IS
OSPF
EIGRP
eBGP
RIP
eBGP (AD 20)