Byung K Lee

US Patent:

20010038471, Nov 8, 2001

Filed:

Jan 5, 2001

Appl. No.:

09/755615

Inventors:

Niraj Agrawal - Hammelburg, DE
Neil Jackman - Freehold NJ, US
Steven Korotky - Toms River NJ, US
Byung Lee - Holmdel NJ, US
Eric Tentarelli - Middletown NJ, US
Liyan Zhang - Columbia MD, US

International Classification:

H04B010/08
H04L001/00
G08C015/00

US Classification:

359/110000, 359/124000, 370/217000

Abstract:

In a telecommunications network, such as an optical mesh network, at a node along a service path satisfying a demand from a start node to an end node, the node can detect a failure in the service path by any of three different ways: (a) by monitoring incoming payload signals from its previous node along the service path for a loss-of-signal (LOS) condition; (b) by monitoring the incoming payload signals from its previous node along the service path for an in-band alarm indication signal; and (c) by monitoring an out-of-band signaling channel for a failure message transmitted from its previous node along the service path. The node then determines appropriate actions as part of a distributed restoration procedure depending on whether the node is an intermediate node or the end node along the service path. If the node is an intermediate node, then the node passes the out-of-band failure message to its next node along the service path. If the nod is the end node, then the node transmits an out-of-band restore message to its previous node along the corresponding restoration path. In both cases, the node proceeds to reconfigure its cross-connect for the transition from the service path to the restoration path.

US Patent:

52553302, Oct 19, 1993

Filed:

Oct 3, 1990

Appl. No.:

7/592396

Inventors:

Tu-Chuong Huynh - Manalapan NJ
Byung H. Lee - Holmdel NJ

Assignee:

AT&T Bell Laboratories - Murray Hill NJ

International Classification:

G06K 966

US Classification:

382 18

Abstract:

A facility is provided which determines the optimum phase of a sample clock signal that is used to acquire a copy of an image containing text. In particular, the phase of the sample signal is set to an initial value and is thereafter incremented by a predetermined amount of time following the acquistion of each of a predetermined number of copies of the image, in which each such copy is defined by respective pixel values. Upon acquiring a current copy of the image, a histogram is formed from ones of the pixel values and is stored in memory in place of a priorly stored histogram if the latest histogram contains more pixel values indicative of text than the priorly stored histogram. The phase of the sample clock signal is then adjusted to the phase associated with the histogram that is stored in memory following the last of such acquisitions.