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Does BGP not use ARP?

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Last Modified: 2012-08-13
I have seen several BGP issues resolved by correcting the mac address the ISP has for the client site or vice versa.

Does BGP not use ARP or is it a different issue?

This is not something that I have run into with other routing protocols such as OSPF and EIGRP.
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Instructor
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Top Expert 2015
Commented:
Any protocol that uses IP unicast at layer 3 over ethernet uses ARP.

Because OSPF and EIGRP use multicast, there is no IP-to-MAC mapping.
Hi,

Since BGP runs over TCP/IP then at some point it will use ARP to resolve the next hop for the BGP peers IP address.

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Commented:
I thought the ISP might use static arp for clients so noboday can spoof the ip address?

Doesn't multicast ride on top of ip which uses arp?
Don JohnstonInstructor
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Top Expert 2015
Commented:
>I thought the ISP might use static arp for clients so noboday can spoof the ip address?

Could be.

>Doesn't multicast ride on top of ip which uses arp?

Multicast IP. OSPF uses 224.0.0.5 and 224.0.0.6. EIGRP uses 224.0.0.10. There are corresponding multicast MAC addresses for the IP's.
Broadcasts use FF:FF:FF:FF:FF:FF

The link shows how IP multicast addresses are mapped to mac addresses.

http://technet.microsoft.com/en-us/library/cc957928.aspx