Open source SDN projects like OpenDaylight are offering an open platform for network programmability to network elements such as routers and switches. They rely on standards-based approaches to provide true multi-vendor support. The IETF (and its various working groups) is moving slowly towards creating the standards needed for widespread SDN development and adoption.
OpenDaylight uses topology models, described in YANG, that are getting standardized in the NETMOD and I2RS IETF working groups. It also uses emerging protocol extensions for PCEP and BGP-LS that are being discussed in the PCE and BGP IETF working groups. OpenDaylight, with more than 200 developers, just last week issued Helium, its second software release.
On the other hand, the IETF is progressing more slowly on standardization. PCEP extensions to support statefullness and PCE-initiated LSP are still in draft form. Major routing vendors are finding it difficult to match up the draft updates to their release cycles. As a result of this, customers are challenged to pair up the draft version supported by their routing software with the controller version.
This slowness can cause other issues. For instance, codepoints proposed in one draft may not be valid anymore, because the IANA approved the same codepoints in another draft that quickly moved to RFC state. This could result in implementations that use the old codepoint in their software version.
This issue was highlighted in a Q&A with Neela Jacques, Executive Director of the OpenDaylight Project, as one of the things that is holding back SDN and NFV adoption.
In the last IETF I2RS WG meeting, the open source community said that its goal is to support the IETF process to produce standard YANG models quickly.
It would greatly help the open source community if the IETF could standardize the relevant SDN technologies quickly.
In my next blog post, I will explain some of the relevant and important work at the IETF, and how implementers/vendors have been adopting it.