drcl.inet.protocol.ospf
Class OSPF_Area

java.lang.Object
  |
  +--drcl.inet.protocol.ospf.OSPF_Area

public class OSPF_Area

extends java.lang.Object

Class OSPF_Area The area data structure contains all the information used to run the basic OSPF routing algorithm. Each area maintains its own link-state database. A network belongs to a single area, and a router interface connects to a single area. Each router adjacency also belongs to a single area. The OSPF backbone is the special OSPF area responsible for disseminating inter-area routing information. The area link-state database consists of the collection of router-LSAs, network-LSAs and summary-LSAs that have originated from the area's routers. This information is flooded throughout a single area only. The list of AS-external-LSAs (see Section 5) is also considered to be part of each area's link-state database. ref: sec. 6

Author:

Wei-peng Chen

See Also:

OSPF, OSPF_LS_Database, OSPF_SPF_vertex, OSPF_Interface, OSPF_Neighbor

Field Summary

protected int	area_id
protected java.util.Vector	if_list THIS router's interfaces belonging to the area.
protected OSPF_LS_Database	ls_db Instead of using three Vector, which are router_lsa_list, network_lsa_list, and summary_lsa_list, we use a database to represent them all.
protected OSPF_SPF_vertex	spf_root Shortest Path Tree.
protected java.util.Vector	vertex_list while vertex_list is the list for all verteies.

Constructor Summary

protected	OSPF_Area() Constructor
protected	OSPF_Area(int id_) Constructor

Method Summary

java.lang.Object	clone()
protected int	count_nbr_in_state(int state) Count the # of neighbors to which belong to this area have the same state as the "state" from the argument
java.lang.String	info(java.lang.String prefix_)
protected void	ospf_lsdb_remove(OSPF_LSA lsa) remove lsa from the area LS database
void	reset()
java.lang.String	toString()

Methods inherited from class java.lang.Object

equals, finalize, getClass, hashCode, notify, notifyAll, wait, wait, wait

Field Detail

area_id

protected int area_id

if_list

protected transient java.util.Vector if_list

THIS router's interfaces belonging to the area. Since each OSPF algorithm keeps a specific area data structure, this field records the interfaces only belonging to this router in this area

ls_db

protected transient OSPF_LS_Database ls_db

Instead of using three Vector, which are router_lsa_list, network_lsa_list, and summary_lsa_list, we use a database to represent them all. Here each area has its own ls database

spf_root

protected transient OSPF_SPF_vertex spf_root

Shortest Path Tree. The following two items are releated, spf_root is the root for the shortest path tree

vertex_list

protected transient java.util.Vector vertex_list

while vertex_list is the list for all verteies. Only vextex on the tree can be associated with spf_root, otherwise, it can be added into vertex_list

Constructor Detail

OSPF_Area

protected OSPF_Area()

Constructor

OSPF_Area

protected OSPF_Area(int id_)

Constructor

Parameters:

id_ - : Area id

Method Detail

clone

public java.lang.Object clone()

Overrides:

clone in class java.lang.Object

toString

public java.lang.String toString()

Overrides:

toString in class java.lang.Object

info

public java.lang.String info(java.lang.String prefix_)

reset

public void reset()

count_nbr_in_state

protected int count_nbr_in_state(int state)

Count the # of neighbors to which belong to this area have the same state as the "state" from the argument

ospf_lsdb_remove

protected void ospf_lsdb_remove(OSPF_LSA lsa)

remove lsa from the area LS database