The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Oct. 25, 1994
Filed:
Feb. 16, 1993
Hiromi Ueda, Kanagawa, JP;
Kenji Akutsu, Kanagawa, JP;
Ryuichi Ikematsu, Tokyo, JP;
Takatoshi Kurano, Tokyo, JP;
Yoshihiro Ashi, Kanagawa, JP;
Yukio Nakano, Kanagawa, JP;
Takafumi Chujo, Kanagawa, JP;
Shigeo Amemiya, Kanagawa, JP;
Nippon Telegraph and Telephone Corporation, , JP;
NEC Corporation, , JP;
Hitachi, Ltd., , JP;
Fujitsu Limited, , JP;
Abstract
In an ATM switching network, ATM (asynchronous transfer mode) self-routing switches are interconnected by facilities carrying STM-N (synchronous transport modules level N) signals. At each inlet of an ATM self-routing switch, an STM overhead is removed from each frame of an incoming STM-N signal to create a vacant interval and the frame is converted according to ATM cell format into a series of data ATM cells, and an idle ATM cell is derived from the vacant interval. A supervisory bit sequence is inserted to the payload field of the idle ATM cell to produce a supervisory ATM cell, and the data and supervisory ATM cells are sent into the ATM switch. At each outlet of the switch, the bit sequence of the supervisory ATM cell is checked to evaluate the quality of the ATM switch and a series of data ATM cells is then converted into an STM-N signal according to STM-N frame format.