Routing (2.2, 5.5, 1.4)
What is PIM Sparse Mode (PIM-SM)
Uses a shared distribution tree and creates an optimal distribution tree through shortest path tree (SPT) switchover
What is PIM Dense Mode (PIM-DM)?
Uses periodic flood and prune behavior to form optimal distribution tree
What is a converged network?
When all routing tables are synced
What is Routing Information Protocol (RIP)?
- A distance vector protocol that uses hop count (maximum hops of 15; 16 is infinite) - Oldest dynamic routing protocol - Updates every 30 seconds - Easy to configure - Runs over UDP - Interior
What is Intermediate System to Intermediate System (IS-IS)?
- A link state protocol that also uses cost and functions like OSPF protocol, but not as widely popular - Interior
What is Open Shortest Path First (OSPF)?
- A link state protocol that uses cost - Cost is based on link speed between routers - Interior
What is Border Gateway Protocol (BGP)?
- A path vector that uses the number of autonomous system hops instead of router hops - BGP is used as the backbone of the internet - Widespread utilization - Slow convergence - Exterior
What is the Router Advertisement Method?
- Characteristic of every routing protocol - Some use Distance Vector - Some use Link State - Some use Hybrid
What are the two modes of PIM?
- Dense Mode (PIM-DM) - Sparse Mode (PIM-SM)
What are some metrics used for some of these routes?
- Hop count - Believability - Reliability - Bandwidth - Delay - Cost - Other
What is Enhanced Interior Gateway Routing Protocol (EIGRP)?
- Hybrid of distance vector and link state protocols that uses bandwidth and delay - Was created by Cisco - Proprietary Cisco protocol that is popular in Cisco-only networks - Interior
What are the 3 variants of IGMP?
- IGMPv1, client requests joining the group and is asked every 60 seconds if it wants to remain in the group - IGMPv2, client can send a leave message to exit multicast group - IGMPv3, client can request multicast only from specific server and allows source-specific multicast (SSM) and multiple video streams to a single multicast stream
What are the two types of routing protocols?
- Internal - External
What is preferred of metrics?
- Lower metrics are preferred over higher metrics
What is Static NAT (SNAT)?
- Manually assigns an IP address and gives a one-to-one translation - Used as a security feature
What are two examples of Link State Protocols?
- OSPF - IS-IS
What is Link State?
- Requires all routers to know about the paths that all other routers can reach in the network - Has a faster convergence time than distance vectors
What are the 2 techniques used to prevent routing loops
- Split Horizon - Poison Reverse
What does NAT do?
- Translates private IP addresses to public IP addresses for routing over public networks
What is Dynamic NAT (DNAT)?
Automatically assigns an IP address from a pool and gives a one-to-one translation
What is the Poison Reverse technique?
Causes a route received on one interface to be advertised back out of that same interface with a metric considered to be infinite
What is a Router?
Forwards traffic between subnets between an internal and external network, or between two external networks
What is a Routing Table?
Helps determine which route entry is the best fit for the network
What is Route Believability?
If a router has a lower administrative distance (AD), the route is more believable
What is a Directly Connected Route?
Learned by a physical connection between routers
What is a Dynamic Route?
Learned by exchanging information between routers
What is Internet Group Management Protocol (IGMP)?
Lets routers know which interfaces have multicast receivers and allows clients to join a multicast group
What is a Static Route?
Manually configured by an administrator
What is Multicast Routing?
Multicast sender sends traffic to a Class D IP address, known as multicast group
What is Hop Count?
Number of routers from the source router through which data must pass to reach the destination network
What is an External Gateway Protocol (EGP)?
Operate between autonomous systems
What is an Interior Gateway Protocol (IGP)?
Operates within an autonomous system
What is the Split Horizon technique?
Prevents a route learned on one interface from being advertised back out of that same interface
What is a Hold-down Timer?
Prevents updates for a specific period of time and speeds up convergence
What is Inside local?
Private IP address referencing an inside device
What is Outside local?
Private IP address referencing an outside device
What is Inside global?
Public IP address referencing an inside device
What is Outside global?
Public IP address referencing an outside device
What is Protocol Independent Multicast (PIM)?
Routes multicast traffic between routers and forms a multicast distribution tree
What is a Distance Vector?
Sends full copy of routing table to its directly-connected neighbors at regular intervals
What is Port Address Translation (PAT)?
Sharing of one public IP by multiple private IP addresses which gives a many-to-one translation
What is convergence?
Time it takes for routers to update their routing tables in response to a topology change
What is Network Address Translation (NAT)?
Used to conserve the limited supply of IPv4 addresses
Are each subnet and external network going to be their own broadcast domain?
Yes
Can Multilayer switches also perform routing functions?
Yes
If you want to make a network more specific, what do you need to do to the route entry?
You need to make the route entry longer
