| as a Router, I do separate Broadcast Domains[T/F] | T |
| when receiving a packet, it stops at the Interface,how to Forward/Route the Packet ? | first let’s check the longest match for this prefix
then decide which routing protocol should handle this task
finally, the desired protocol will submit it’s own “Rules” (Metrics)
To route the packet |
| what is two type of dynamic routing protocol? with examples | 1-distance vector :
R & D
cares about shortest way
2-Link static :
Is-Is & OSPF
cares about bandwidth |
| what is administrative distance for Static ? | 1 |
| what is administrative distance for OSPF ? | 110 |
| what is administrative distance for RIP ? | 120 |
| what is administrative distance for BGP ? | 20 |
| general info about static protocol | - the only method of manually routing a specific packet
To a specific route
- has no metric
- manual routing
- the first next-hop can either be the egress interface Port ID
Or, the next reachable IP Address
- Available for IPv4 & IPv6 |
| what is Static Route Flavors: ? | - Default Route: every un-mentioned subnet to be routed here
also, can be a default Gateway.
- Floating Static: a hidden back-up plan. |
| what is (OSPF) ? | open shortest path first protocol
- Dynamic Routing Protocol
- administrative Distance = 110
- Metric = Cost (lesser = Better)
- was use Dijkstra algorithm .
- now use SPF algorithm for route decision .
- Process ID for multiple instances
- Area ID for Data Base isolation |
| what is Link-State Advertisements ? | negotiation between OSPF Routers.
- it contains:
- LSRequest: provide the missing Information
- LSUpdate: reply for the LSR
- LSAcknowledgement: reply for the LSU |
| why we use LSA (Link State Advertisement) ? | in OSPF Protocol, when there is missing information for the data base (LSDB) |
| what is administrative distance for EIGRP ? | 90 |
| OSPF Neighboring Process: | .. |
| what is P2P in ospf routers ? | - a Neighboring router can be a P2P neighbor
- in this case no problems |
| what happened when a switch become between routers using ospf ? | - broadcast storm will happen
- elections must take place |
| how elections happens in ospf to choose the DR ? | - only One router should update the topology (DR)
- a DR (Designated Router): Highest Router Priority (0-255), Def=128
Or Highest Router ID
- Router ID (R.ID): 32-bit Address
- DR needs BDR (second best of everything) |
