# Finding Source Routing Paths

DevFeed: [Finding Source Routing Paths](<https://devfeed.tech/articles/finding-source-routing-paths-11208.md>)

Original publisher: [Read original article](<https://blog.ipspace.net/2025/06/source-routing-paths/>)

Published: 2025-06-13T06:10:00Z

Content type: tutorial

Language: en

Sources: [ipSpace.net blog](<https://devfeed.tech/sources/ipspace-net-blog.md>)

Topics: [networking](<https://devfeed.tech/topics/networking.md>), [Software-defined networking](<https://devfeed.tech/topics/sdn.md>), [Network architectures](<https://devfeed.tech/topics/network-architectures.md>), [IS-IS](<https://devfeed.tech/topics/is-is.md>)

Tags: [is-is](<https://devfeed.tech/tags/is-is.md>), [management](<https://devfeed.tech/tags/management.md>), [network](<https://devfeed.tech/tags/network.md>), [networking](<https://devfeed.tech/tags/networking.md>), [networking-fundamentals](<https://devfeed.tech/tags/networking-fundamentals.md>), [ospf](<https://devfeed.tech/tags/ospf.md>), [protocol](<https://devfeed.tech/tags/protocol.md>), [routing](<https://devfeed.tech/tags/routing.md>), [sdn](<https://devfeed.tech/tags/sdn.md>), [software](<https://devfeed.tech/tags/software.md>)

## AI overview

This tutorial explains how source-routing paths are determined and installed across networks. It examines centralized controller-based routing, SDN and OpenFlow, and segment routing with Path Computation Elements, then compares these approaches with older virtual-circuit provisioning systems.

## Source excerpt

In the previous blog post, we discussed the generic steps that network devices (or a centralized controller) must take to discover paths across a network. Today, we'll see how these principles are applied in source routing, one of the three main ways to move packets across a network. Brief recap: In source routing, the sender has to specify the (loose or strict) path a packet should take across the network. The sender thus needs a mechanism to determine that path, and as always, there are numerous solutions to this challenge. We'll explore a few of them, using the sample topology shown in the following diagram. Read more ...