I frequently see people asking if 3550s are sufficient for CCIE lab preparation, or if 3560s are a must. Of the top of my head I know that QoS differs between the 3550 and 3560, and also that the 3550s do not support Private VLANs. Beyond that, I can’t say much. Today I stumbled across a comparison from Internetwork Expert. This is really great information. Here’s what they’ve laid out:

Catalyst 3560 Only Features [12.2(25)SEE2]

Access Switch Device Manager (SDM) Template
IEEE 802.3af Power over Ethernet
IGMP Throttling
IPv6 (Internet Protocol Version 6)
MLD Snooping
Private VLANs
VLAN-Based QoS on Physical Ports
SRR (Shaped Round Robin)
Weighted Tail Drop (WTD)
Auto-MDIX

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