White Papers

Download our white paper to learn more about inbound and outbound routing, how a router decides which path is best, localpref, MED and AS-PATH rules, and best practices.

Here is a preview:

Basic information:

• You define where packets leave your network
• The other party defines which route is used to route the packets back to you
• In most cases, the Internet is not routed symmetrically

Routing outbound

Routing packets from your network to the other network are defined by you.

• Your router sends outgoing packets on the basis of its routing table
• The routing table is built up based on learned (=incoming) prefixes from neighbors
• Prefixes are typically learned from:

1. Transit sessions
2. Peering sessions (IXP or PNI)
3. Customer sessions

• If you have more than one router, your routers synchronize their learnings via IBGP

First, you have to learn a route from outside; then you can use it to send packets there.

• In an advanced network, your router sees the prefixes from the target network on different paths
• As there is more than one way of learning prefixes, you have to define where the outbound packet should be sent

Fill in the form to download the white paper!