IP Source Guard vs. DAI (Dynamic ARP Inspection)


(Lukas E) #1

Hello,

could you please explain the difference between IP Source Guard and DAI? Both features uses the DHCP snooping binding table and check the mapping between IP and MAC. Is the difference that DAI proctect against ARP spoofing and IP source guard against IP spoofing?

ARP spoofing: Update other Clients/Router ARP table with spurious entries?
IP spoofing: Change the source IP to another IP address within the packet?

Please correct me if I’m wrong or if you have a good explanation.

Thanks a lot.

Regards,

Lukas


(Lazaros Agapides) #2

Hello Lukas

According to Cisco:

DAI is a security feature that validates ARP packets in a network. DAI intercepts, logs, and discards ARP packets with invalid IP-to-MAC address bindings. This capability protects the network from some man-in-the-middle attacks.

and

IP Source Guard provides source IP address filtering on a Layer 2 port to prevent a malicious host from impersonating a legitimate host by assuming the legitimate host’s IP address. The feature uses dynamic DHCP snooping and static IP source binding to match IP addresses to hosts on untrusted Layer 2 access ports.

I think based on the above, your explanation is more than sufficient.

I hope this has been helpful!

Laz


(Lukas E) #3

Hello Laz,

thanks a lot for your answer.

Kind regards,

Lukas