In-vehicle networks (IVN) have been standardized from the beginning. The story of IVN standardization started at the beginning of the 90s. Today, several IVN technologies have been internationally standardized by ISO (International Organization for Standardization) including the related conformance test plans. But as all electronic technologies, IVNs are a matter of improvement and change due to new requirements and gained experiences. This makes it difficult to always keep the standard backwards compatible, in particular if immature approaches are submitted. Furthermore, new communication protocols are knocking on the door of international standardization bodies. The automotive industry itself is conservative and adapts new IVNs slowly. There are also concerns regarding too many different bus systems and networks in one vehicle. This paper discusses the benefits and challenges of the standardization of IVNs.