Cisco 500 Series Administration Guide

Security
ARP Inspection
Cisco 500 Series Stackable Managed Switch Administration Guide 474
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- No Snoop VLAN—DHCP Snooping is not enabled on the VLAN.
- Trusted Port—Port has become trusted.
- Resource Problem—TCAM resources are exhausted.
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ARP Inspection
ARP enables IP communication within a Layer 2 Broadcast domain by mapping IP
addresses to a MAC addresses.
A malicious user can attack hosts, switches, and routers connected to a Layer 2
network by poisoning the ARP caches of systems connected to the subnet and by
intercepting traffic intended for other hosts on the subnet. This can happen
because ARP allows a gratuitous reply from a host even if an ARP request was not
received. After the attack, all traffic from the device under attack flows through the
attacker's computer and then to the router, switch, or host.
The following shows an example of ARP cache poisoning.
ARP Cache Poisoning

Cisco 500 Series Specifications

General

Model	Cisco 500 Series
Category	Switch
Mounting	Rack-mountable
Management	Web-based, CLI, SNMP
Ports	24, 48
Port Speed	10/100/1000 Mbps
PoE Support	Available on some models
Switching Capacity	Up to 176 Gbps
MAC Address Table Size	16, 000 entries
Security	ACLs, 802.1X
Quality of Service (QoS)	Yes
Dimensions	Varies by model
Weight	Varies by model
Humidity	10% to 90% non-condensing
Power Supply	Internal
Power Consumption	Varies by model
Jumbo Frame Support	Up to 9216 bytes