Carrier Supporting Carrier – The whole story (2)

In this post we are going to discuss both CSC options that we have highlighted in the previous post in details. The two available options are either an ISP customer carrier, or a BGP/MPLS VPN customer carrier. We are going to conquer the control plane and data plane separately, in order to well understand the complete architecture operation. We are also going to separate the control plane into three phases; the backbone carrier network, the CSC peering and the customer carrier network. From the control plane prospective, the backbone carrier and the CSC peering parts are identical in both options, …

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Carrier Supporting Carrier – The whole story (1)

After I’ve completely illustrated the Inter-AS MPLS VPN solution with all its options, I’ve decided to cover the Carrier Supporting Carrier with all its options as well. It was described as Carriers’ Carriers in draft-ietf-2547bis section 9 and followed in the final RFC 4364, and was named Carrier Supporting Carrier by Cisco, and Carrier of Carriers by Juniper. Carrier Supporting Carrier solution enables small service providers to use the cloud of another large service provider in order to connect parts of their own networks, using the transport services provided by another service provider in this manner eliminates the need for …

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Inter-AS MPLS VPN – The whole story – Updated Dec 2008

While doing the final preparations for my CCIE SP track written exam, I reviewed my Inter-AS MPLS VPN posts and I found out that they needed some modifications to be more organized and comprehensive, please revisit the updated posts: Inter-AS MPLS VPN – The whole story (1) Option 1(10A): Back-to-Back VRF – Inter-AS MPLS VPN – The whole story (2) Option 2 (10B): ASBR-to-ASBR / MP-eBGP for VPNv4 – Inter-AS MPLS VPN – The whole story (3) Option 3 (10C): Multi-Hop MP-eBGP Between RR and eBGP Between ASBRs – Inter-AS MPLS VPN – The whole story (4) Option AB – …

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I woke up in the morning and the internet was not there

It was Friday 19 Dec, exactly 9:30 in the morning when I got a call from our NOC team informing me that our BGP peering session is in idle state with our main provider; idle means that the router is not even trying to establish a connection and since this is a direct connection I thought that the interface was down and it may be a physical problem, checking proved my assumptions so I asked them to escalate the case to the transmission engineers (this is SONET interface). I did not engage myself because we were prepared for that and …

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BGP 4-byte AS numbers

Today, we received an email from AfriNIC stating that starting from January 2009 they are going to assign 4 bytes AS numbers by default unless otherwise specified. They are asking providers to upgrade their routers to support the new format. I thought it may be nice to explore the story with you without delving in much technical details: 1. What is a 4-byte AS number and is it different from the 2-byte format ? The 2 byte format allowed for 65,535 different AS numbers (2^16). The new 4-byte formatĀ  allows 4294967295 different AS numbers (2^32). The numbers from 0 to …

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