Netband Project - IP Source Guard
From Teknologisk videncenter
IP Source Guard
This page is part of the Netband Project
- IP source guard is a security feature that restricts IP traffic on nonrouted, Layer 2 interfaces by filtering traffic based on the DHCP snooping binding database and on manually configured IP source bindings. You can use IP source guard to prevent traffic attacks caused when a host tries to use the IP address of its neighbor.
- IP source guard is supported only on Layer 2 ports, including access and trunk ports
- An ACL is applied to the interface, which allows only IP traffic with a source IP address in the IP source binding table and denies all other traffic.
- Filtering options
- Source IP address
- The switch forwards IP traffic when the source IP address matches an entry in the DHCP snooping binding database or a binding in the IP source binding table.
- Source IP and MAC Address
- The switch forwards traffic only when the source IP and MAC addresses match an entry in the IP source binding table.
- Filters both ip and non-ip traffic
- Port security is used to filter source MAC addresses
- Is not supported on pvlan
- Source IP address
Configuration
DHCP snooping must be configured correctly, for IP source guard to work properly.
Source IP -and Mac address filtering
interface FastEthernet0/10 ip verify source port-security
Source IP address filtering
interface FastEthernet0/10 ip verify source
Statically assigned IP -and Mac address entry
ip source binding 0003.47C9.A1D8 vlan 3 10.1.1.11 interface Fa0/1
Verification
HQSW1#sh ip source binding MacAddress IpAddress Lease(sec) Type VLAN Interface ------------------ --------------- ---------- ------------- ---- -------------------- 00:03:47:C9:A1:D8 10.1.1.11 infinite static 3 FastEthernet0/1 00:1B:2A:79:5F:53 10.1.2.52 185 dhcp-snooping 5 FastEthernet0/13 00:03:47:C9:9F:AC 10.1.1.10 233 dhcp-snooping 3 FastEthernet0/2 00:21:5A:F7:F1:01 10.1.2.50 228 dhcp-snooping 5 FastEthernet0/11 Total number of bindings: 4