In case of layer 3 VPN, two labels are normally carried by packet. But the differentiation between the labels is ipv4 and vpnv4.
Ipv4 label is used for IGP and vpnv4 label is used for customer route.
Normally a question comes in mind, “Is LDP responsible for both the labels”.
The answer is no because LDP is only responsible for the top most label is IGP label and MP-iBGP is responsible for vpnv4 label which is present under beneath of IGP label.
Even if the core network is not running LDP, but MP-iBGP is enabled from PE to PE, we can easily see the vpnv4 labels exchange. But the problem is that traffic forwarding will not happen because the core network doesn’t understand the labels.
Ipv4 label is used for IGP and vpnv4 label is used for customer route.
Normally a question comes in mind, “Is LDP responsible for both the labels”.
The answer is no because LDP is only responsible for the top most label is IGP label and MP-iBGP is responsible for vpnv4 label which is present under beneath of IGP label.
Even if the core network is not running LDP, but MP-iBGP is enabled from PE to PE, we can easily see the vpnv4 labels exchange. But the problem is that traffic forwarding will not happen because the core network doesn’t understand the labels.
No comments:
Post a Comment