Routing Fundamentals Flashcards
router
forwards traffic between subnets, between an internal and external network, or between two external networks
routing table
helps determine which route entry is the best fit for the network
Directly Connected Route
Learned by physical connection between routers
Static Route
Manually configured by an administrator
Dynamic Route
Learned by exchanging information between routers
Interior Gateway Protocol (IGP)
Operates within an autonomous system
Exterior Gateway Protocol
Operate between autonomous system
Distance Vector
Sends full copy of routing table to its directly-connected neighbors at regular internval
Convergence
Time it takes for routers to update their routing tables once the topology is changed
Hold-down Timer
prevents updates for a specific period of time and speeds up convergence
Hop count
how many times I have to go through another router to get there
Link state
considering speed of the link and most bandwidth to get to destination; requires all routers to know about the paths that all other routers can reach
RIP (routing information protocol)
a distance vector protocol that uses hop count (maximum hops of 15; 16 is infinite); updates every 30 seconds
Open Shortest Path First (OSPF)
a link state protocol that uses cost
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
Enhanced Interior Gateway Routing Protocol (EIGRP)
Hybrid of distance vector and link state protocols that uses bandwidth and delay
Border Gateway Protocol (BGP)
a path vector that uses the number of autonomous system hops instead of router hops (only exterior protocol)
Dynamic NAT (DNAT)
Automatically assigns an IP address from a pool and gives a one-to-one translation
Static NAT (SNAT)
Manually assigns an IP address and gives a one-to-one translation
Port Address Translation (PAT)
Sharing of one Public IP by multiple private IP addresses which gives a many-to-one translation; most popular
Inside local
private ip address referencing an inside device
inside global
public IP address referencing an inside device
Outside global
public IP address referencing an outside device
outside local
private IP address referencing an outside device
Multicast Routing
Multicast sender sends traffic to a Class D IP, known as a multicast group
IGMP
Lets routers known which interfaces have multicast receivers and allows clients to join a multicast group
PIM (protocol independent multicast)
Routes multicast traffic between routers and forms a multicast distribution tree
