
396 Chapter 9 • Optimizing Network Performance with Queuing and Compression
RED is recommended only for TCP/IP networks. It is not recommended
for protocols such as AppleTalk or Internetwork Packet Exchange/
Sequenced Packet Exchange (IPX/SPX), which respond to dropped packets
by retransmitting the packets at the original rate.
Tail Drop
Tail dropping occurs when the egress queues become so congested that no
more packets can enter the queue. These packets have nowhere to go so
they are dropped from the tail end of the queue. Once packets start to tail-
drop, the current network session will go to timeout mode. These timeouts
can cause each sender to simultaneously ...