CCNA_OSPF - = OSPF (OPEN SHORTEST PATH FIRST) = -OSPF:...

Info iconThis preview shows pages 1–2. Sign up to view the full content.

View Full Document Right Arrow Icon
========================================================================== OSPF (OPEN SHORTEST PATH FIRST) ========================================================================== -------------------------------------------------------------------------- OSPF: FIRST TIME CONVERGENCE PROCESS : -------------------------------------------------------------------------- 1. Neighbor discovery occurs by broadcasting HELLO messages to the multicast IP address of 224.0.0.5. HELLO messages follow the IP packet header with the IP packet protocol type of 89 HELLO message contains the following information from the source router o RID o OSPF Area ID o HELLO interval o DEAD interval o Router priority o DR - Designated Router o BDR -Back-up Designated Router o current list of neighbors A neighboring router "confirms" the HELLO message that it receives by adding the source router into its neighbor list in its own HELLO message. When a router receives its own RID it believes that two- way communication has been established. This permits the LSA topology exchange. To become a neighboring router, the following criteria must be met: o Subnet Mask o Subnet Number (calculated using IP address and subnet mask) o HELLO interval o DEAD interval o OSPF Area ID 2. and neighbor table is created 3. Topology is exchanged with neighbors via LSA (Link State
Background image of page 1

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full DocumentRight Arrow Icon
Image of page 2
This is the end of the preview. Sign up to access the rest of the document.

This note was uploaded on 08/12/2009 for the course CNT 150 taught by Professor Smith during the Spring '09 term at Cochise College.

Page1 / 3

CCNA_OSPF - = OSPF (OPEN SHORTEST PATH FIRST) = -OSPF:...

This preview shows document pages 1 - 2. Sign up to view the full document.

View Full Document Right Arrow Icon
Ask a homework question - tutors are online