When composing a new Network Operating System (Infix) several key decisions have to be made. Infix is based on Buildroot, a very well maintained embedded Linux distribution, which in itself provide only the bare necessities to create and maintain a full operating system. It comes with native Linux /etc/ configuration files and a shell prompt.

Earlier experience have shown most customers rarely have the expertise to handle embedded Linux systems this way, much less configure and set up intricate networking services. Nor should they have to! Providing a user-friendly command line interface (CLI) and/or web interface is a key selling point. However, manually maintaining modeling and syntax is very hard and time consuming, not to mention difficult to get right.

Therefore, we decided early on to build on the work done by IEEE and IETF in modeling common settings and behavior of networking devices. Although fairly comprehensive, they provide a complete and coherent view of a switch or router. It is our job to make it user-friendly!

Criteria

Setting out to find a suitable Open Source component to fill this void we had the following requirements (RFC2119):

  • Must use YANG for modeling
  • Must support NETCONF for remote management
  • Must have good documentation
  • Should be an active/maintained project
  • Should support RESTCONF
  • Should have at least rudimentary command line tools
  • Optional support for CORECONF

Evaluation

While many alternatives exist, the two contenders in our evaluation are Sysrepo and Clixon. A basic comparison of features shows them on sort of equal pairing:

Feature Sysrepo Clixon
Data store ✔ ✔
YANG libyang native
NETCONF netopeer2 native
Documentation ✔ ✔
Maintained ✔ ✔
RESTCONF - native
CLI netopeer2-cli autocli
CORECONF - -

Both projects have traction and is in active use. For example, Deutsche Telekom have built sysrepo plugins for:

So initially we were leaning towards Sysrepo, much thanks to existing plugins. However, Clixon’s native support for RESTCONF (read+write) and the excellent, from YANG models, automatically generated CLI is what in the end tilted the scales in favor of Clixon. Sure, sysrepo has the upcoming Rousette plugin but that is not yet finished. We want to spend our time building value for our customers, so the more of the basic framework-y things we can get out of the box and not have to worry about, the better.

We’ve already started an implementation of the IETF System model in Clixon using Augeas to modify files in /etc and next up we’ll do IETF Interfaces and start looking into the IEEE 802.1Q bridging model as well. For the initial drops we will not need much more than that for Infix.

Honorable Mention

The OpenCPE project, with freenetconfd, mand, etc. for OpenWRT is a very interesting alternative for those looking into using OpenWRT as a base for their product.

About AEL

At Addiva Elektronik we specialize in networking and power solutions. Both from a hardware and embedded software perspective, offering our customers a from “farm to table” experience.

We have strategic partnerships with both Marvell and Microchip and have extensive experience building managed Ethernet switches for demanding industrial applications.

For more information, see: https://addiva.se