Subject: [bess] one additional use case for L3VPN Prefix ORF (i.e., path optimization in hybrid cloud scenarios)

From: Xuxiaohu <[email-masked]>
Date: Thu, 14 May 2015 08:01:26 +0000

Hi all,

In the hybrid cloud scenario where the private cloud (i.e., the on-premises data center) is connected to the public cloud via service providers' L3VPN, if a subnet in the public cloud is extended across multiple DC locations (either via L3VPN or L2VPN), the L3VPN PE on the private cloud site could achieve path optimization by learning host routes originated from the public cloud. However, it may not be advisable to learn all remote host routes for the PE router due to the routing table scaling concern.

With the L3VPN-prefix-ORF as defined in (https://tools.ietf.org/html/draft-xu-bess-l3vpn-prefix-orf-01), the PE router now could learn remote host routes on demand. For instance, the PE router could just learn those host routes for which there are a certain volume of traffic. 

Best regards,
Xiaohu