The other major interconnection is the Western Interconnection. The two major interconnections are the Eastern Interconnection and the Western Interconnection. Multiple types of multistage interconnection networks exist. Direct interconnection refers to the interconnection between two network domains without any intermediate network domain. X.75 and X.121 allowed the interconnection of national X.25 networks. Most notably, IEEE 1547 sets the standard for interconnection and interoperability of distributed energy resources. A mesh refers to rich interconnection among devices or nodes. Thereby accelerating the realization of the interconnection of all things. Clear Communications reached an agreement with Telecom in 1995 on local service interconnection. This article lists protocols, categorized by the nearest layer in the Open Systems Interconnection model. SNET is composed of the interconnection of many Nodes. Molex connector is the vernacular term for a two-piece pin and socket interconnection. Standardization is therefore not the only solution for "open systems interconnection". The DERTF is a working laboratory for interconnection and systems integration testing. Although many countries had telegraph networks, there was no "worldwide" interconnection.