Netgear GSM7228PS - ProSAFE 28 ports Gigabit Ethernet L2 Managed Stackable Switch with PoE Guía De Administador
Chapter 7. OSPF
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7.
OSPF
Open Shortest Path First
This chapter provides the following examples:
• OSPFv3
For larger networks Open Shortest Path First (OSPF) is generally used in preference to RIP.
OSPF offers several benefits to the administrator of a large or complex network:
OSPF offers several benefits to the administrator of a large or complex network:
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Less network traffic:
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Routing table updates are sent only when a change has occurred.
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Only the part of the table which has changed is sent.
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Updates are sent to a multicast, not a broadcast, address.
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Hierarchical management, allowing the network to be subdivided.
The top level of the hierarchy of an OSPF network is known as an autonomous system (AS) or
routing domain, and is a collection of networks with a common administration and routing
strategy. The AS is divided into areas: Intra-area routing is used when a source and destination
address are in the same area, and inter-area routing across an OSPF backbone is used when
they are not. An inter-area router communicates with border routers in each of the areas to which
it provides connectivity.
routing domain, and is a collection of networks with a common administration and routing
strategy. The AS is divided into areas: Intra-area routing is used when a source and destination
address are in the same area, and inter-area routing across an OSPF backbone is used when
they are not. An inter-area router communicates with border routers in each of the areas to which
it provides connectivity.
The 7000 Series Managed Switch operating as a router and running OSPF determines the best
route using the assigned cost and the type of the OSPF route. The order for choosing a route if
more than one type of route exists is as follows:
route using the assigned cost and the type of the OSPF route. The order for choosing a route if
more than one type of route exists is as follows:
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Intra-area.
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Inter-area.
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External type 1: The route is external to the AS.
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External type 2: The route was learned from other protocols such as RIP.