As I mentioned in the previous L3VPN posts, those were using one specific architecture to connect two ISPs to each other, which is called Back to Back VRFs where a VRF is needed for each customer in both ISPs networks. Of course this is one way of making this to work. Another design is called carrier supporting carrier which I'm going to explain in this post. I'm going to use the same previous design with some slight changes, HERE is the complete diagram. There are no changes in the customer sites configuration and they are exactly as I left them in the previous MPLS VPN series, so I am not going to copy their configuration here. All the configuration changes happen in both ISPs
Tag: MPLS
L3VPN Part 1 of 5
L3VPN was one of the recent challenges for me in routing and switching world as it introduces many new concepts that change conventional routing as we know it, but with a lot of reading, lab scenarios I became quite comfortable with L3VPN now. To be honest, even though it is really a complex topic, I think most of the books were not doing a good job explaining this. I had to read CCIE cert guide, BGP implementation and then MPLS fundamentals to finally be able to work some lab scenarios. Only then, I started to get the big picture of how L3VPN works. Now I am glad to share what I learnt so far in this post. I will try to