Peering in the Internet routing world is complex. Service providers use BGP to establish peering and in peer-to-peer relationships between similar tier providers, there is usually no compensation involved for transmitting the other’s traffic. The advantage for each provider is that they improve user experience due to the shorter delays when communicating with services hosted by the other provider.
Under such circumstances, entering into a peering relationship with another provider should be done after understanding its impact. For example, consider a peer-to-peer relationship between Provider A and B. If Provider A pushes more traffic through transit than Provider B, then it puts provider B at a disadvantage because they are now transmitting with no cost advantages. Therefore, it is important for service providers to verify that a peering agreement with another provider does not put them at a disadvantage and that the traffic exchanged during transit is symmetric in both directions.
This starts with traffic visibility. A provider must be aware of where their traffic is coming from or going to (source and destination AS), how much of this traffic is from their peers (neighbor AS) and how much of this is transit traffic (transit AS). The next is the ability to understand the impact of peering changes. When a provider needs additional or new transit capacity, they must be able to determine whether it makes sense to upgrade the capacity of existing links or peer with a new provider to carry the additional traffic load.
It is possible to gather traffic information using flow analytics technologies such as NetFlow or IPFIX. But looking at traffic data gathered from individual routers does not allow a provider to understand the exact routing path taken by the traffic. Providers need comprehensive visibility into traffic behavior over routing paths to make informed decisions and then optimize their BGP peering.
This is where the Packet Design Explorer Suite with its patented Route-Flow Fusion technique can help. By combining route and traffic analytics, the Explorer Suite can compute the complete path of traffic and show the internal and external links, routers, upstream and downstream neighbor AS, source and destination AS, and even the transit AS. This information helps the network engineer gain rich visibility into traffic, including into those links from which flows are not exported, along with de-duplication of traffic flows.
Route-Flow Fusion can do a lot more. For example, it can help find the transit AS that may pass through traffic from each source AS when peering directly, provide highly granular information about the traffic to and from upstream and downstream AS, compute the before and after traffic volumes on links and AS during network modeling, and provide the ability to model the adding and downing of BGP peerings.
Interested to know more? Download the “Understanding and Optimizing BGP Peering Relationships” white paper to learn more about how the Explorer Suite can help you take informed peering decisions.