Karteikarten
SCC 203 - Advanced Routing Protocol
Karten in diesem Stapel (22)
- 1What are the two approached to configuring routes?– Non-Adaptive/ Static
– Adaptive/ Dynamic - 2How is non-adaptive/static configuration achieved?• Always used to add local (to device) interfaces to table
• Manually configure any additional routes
• Relies on administrator establishing consistent routes …on devices across networks under their contro - 3How is adaptive/dynamic configuration achieved?• Routers run distributed algorithm
• Aim to establish best path between any two points
• Depends on Routing Protocols - 4What are the two classes of routing protocol?Intra-domain protocols
Inter-domain protocols - 5What does interior gateway protocol manage?Manages traffic within an adminstrative domain
- 6What does exterior gateway protocol manage?– Manages traffic between administrative domains
- 7Interior gateway protocol have limited scope of domain. Why could this be a problem?– Limited scope of domain allows more complex algorithms
- 8What do exterior gateway protocol ignore?– Ignores internal structure of the domains it connects
– Protocol design limited by global scale - 9Why is RIP (route information protocol) a problem?– Poor scalability, Count to Infinity issues, and slow convergence
- 10What does intermediate to intermediate protocol enable?– Can route multiple network protocols simultaneously
Adopted by many ISP's - 11What are OSPF advantages?Converges quickly without loops
• Supports multiple (precise) metrics simultaneously
– e.g. Throughput, Delay, Cost, Reliability,
• Can load-balance over multiple paths to destination
Separate representation of external routes - 12What is the link state routing tasks?. Discover neighbours and their addresses
• Find distance/ cost/ … metric to each neighbour
• Build announcement packet with all information
• Send announcement to all other routers
• Compute shortest path to all routers - 13How is the network communication achieved in link state?– Announce to all nodes
• Link cost to immediate neighbors
– Each node learns full network structure
– All nodes compute all shortest paths independently - 14How is the network communication achieved in distance vector?– Announce to immediate neighbors
• Least cost distance to all nodes
– No complete picture
– Distributed ‘computation’ of ‘shortest’ paths - 15Compare both protocols in terms of higher message overhead?• Link state: O( nodes * links )
– Errors bounded: nodes build routing tables independently
• Distance vector: O( iterations * links )
– Iterations ideally = network diameter, loops make this worse
– Errors propagate: routing tables shared to other nodes - 16Compare both protocols in terms of higher processing cost?• Link state: O( N2); with optimization approach O( N log(N) )
• Distance vector: O( iterations * nodes ) - 17Problem with using OSPF on broadcast networks?On shared network would have full mesh for updates
– Every router would share updates with every other
– Highly inefficient - 18Why do we elect a designated router? What does this result to?In order for all other routers to synchronize with the device
– Results in n updates not n * (n – 1) / 2 - 19How do we handle failure on Broadcast networks?– Routers maintain synchronisation with both
– Giving 2n – 1 updates - 20What is the stub area?Area only having default route for external networks
- 21Why are there slight variations on stub area?– Each allowing slightly differing participation in inter-area route propagation
- 22—
Informationen
- Beschreibung
- Karteikarten am SCC 203 - Advanced Routing Protocol, erstellt von Ayo Olutobi am 27/04/2017.
- Erstellt von
- Ayo Olutobi
- Aufrufe
- 1
- Bewertung