Queuing Mechanisms Objectives

show queue

• Router#show queue serial 1/0
• Input queue: 0/75/0 (size/max/drops); Total output drops: 0
• Queueing strategy: weighted fair
• Output queue: 2/1000/64/0 (size/max total/threshold/drops)
• Conversations 2/4/256 (active/max active/max total)
• Reserved Conversations 0/0 (allocated/max allocated)
• (depth/weight/discards/tail drops/interleaves) 1/4096/0/0/0
• Conversation 124, linktype: ip, length: 580
• source: 193.77.3.244, destination: 20.0.0.2, id: 0x0166, ttl: 254,
• TOS: 0 prot: 6, source port 23, destination port 11033
• (depth/weight/discards/tail drops/interleaves) 1/4096/0/0/0
• Conversation 127, linktype: ip, length: 585
• source: 193.77.4.111 destination: 40.0.0.2, id: 0x020D, ttl: 252,
• TOS: 0 prot: 6, source port 23, destination port 11013

Queuing Comparison

• Weighted Fair Queuing

• Priority Queuing

• Custom Queuing

• No queue lists

• Low-volume traffic given priority

• Conversation dispatching

• Interactive traffic gets priority

• Works well on speeds up to 2 Mbps

• Enabled by default

• 4 queues

• High-priority queue serviced first

• Packet-by-packet dispatching

• Critical traffic gets through

• Designed for low-bandwidth links

• Must configure

• 16 queues

• Round-robin service

• Threshold dispatching

• Proportional allocation
• of bandwidth

• Designed for medium-speed links

• Must configure