The ESX Family has impressive Technical Specifications :

Hardware

Architecture

Up to10/20 Gbps full-duplex, non-blocking distributed fabric; three-tier Integrated Network Services Switching architecture; independent scaling and protection of management, control, and data planes; application and service agent plug-ins; open, extensible multi-service platform based on Windows NT® embedded OS

Network Services Controller
Intel Pentium II-based controller running Windows NT Server

Modules and Line Cards

	• 10/100TX: 48 to 192/384 ports; auto-sense 10/100
	• 100FX: 24 to 96/192 ports
	• 1000SX: 6 to 24/48 ports
	• Up to 400 MB of packet buffering
	• Multi-link trunking: up to 16 Gigabit or 10/100 links per trunk

Output Buffers
1 MB per 100 Mbit port, 10 MB per Gigabit port

Scalability
Maximum Number of MAC Addresses . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .20K
Maximum Number of Routes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .16K
Maximum Number of ARP Entries . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .2K
Maximum Number of VCs . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .20K
Maximum Number of LECs . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .16

Bandwidth Management
Wire speed L2/L3/L4 stateful application classification; up to 4 QoS queues on all Ethernet ports

Management Interfaces
In-band Ethernet, Out-of-band Ethernet and serial interface connector per card

Performance Up to 38 Mpps IP routing; Layer-2 = Layer-3 = Layer-4 = Wire speed; perfect parallel hardware multicast; less than 15uS transit latency