Bell No. 1 ESS
The Bell No.1 Electronic Switching System (1ESS) is the first regularly used switching center for telecommunications that was purely memory-programmed. 1ESS was first put into operation in 1965 in Succasunna, NJ , USA.
1ESS uses a redundant central processor in Harvard architecture . Since then, telecommunications services can be programmed flexibly.
The compatible successor system was the 1ASS with a faster processor and a more compact structure than the previous system. 1ASS was introduced in 1976.
The last # 1 ESS exchange in the United States of America was in Odessa (Texas) and was converted to a VoIP-based system on June 17, 2017. It was in operation for 43 years.
Individual evidence
- ↑ Ketchledge RW. "The No.1 Electronic Switching System" IEEE transactions on communication technology, Vol 13 No. 1, March 1965, 38-41.
- ↑ Tuomenoska LS, Ulrich W .: "Problems of Programming for Shared Real-Time Systems" IEEE transactions on communication technology, Vol. 15 No. 1, Feb. 1967, 5-10
- ↑ 1A Processor , Bell System Technical Journal, 56 (2), 119 (February 1977)
- ↑ Nokia OnLine Customer Support (OLCS) - 1AESS ( Memento from October 4, 2016 in the Internet Archive )