How many times a unacknowledge packet is retransmitted?

• Two types of packets in EIGRP—
unreliable and reliable
Hellos and Acks are unreliable
Updates, queries, and replies are reliable
• Reliable packets require an acknowledgement

If not acknowledged, packets are retransmitted, up to 16 times!

• 16 retransmits must occur AND hold time period must expire before declaring the
neighbor down.
• Retransmissions based on RTO, which is derived from SRTT
• 16 retransmits takes between 50 seconds and80 seconds

~ by mustafagolam on December 15, 2008.