Specifications

Glossary
GL-11
Cisco ONS 15454 Troubleshooting and Maintenance Guide
November 2001
STS-1
Synchronous Transport Signal 1. Basic building block signal of SONET, operating at 51.84 Mbps for transmission over OC-1
fiber. Faster SONET rates are defined as STS-n, where n is a multiple of 51.84 Mbps. See also SONET.
Subnet mask
32-bit address mask used in IP to indicate the bits of an IP address that are used for the subnet address. Sometimes referred to
simply as mask. See also IP address mask and IP address.
Subnetwork
In IP networks, a network confined to a particular subnet address. Subnetworks are networks segmented by a network
administrator in order to provide a multilevel, hierarchical routing structure while shielding the subnetwork from the
addressing complexity of attached networks. Sometimes called a subnet.
Subtending rings
SONET rings that incorporate nodes that are also part of an adjacent SONET ring.
Superuser
A security level that can perform all of the functions of the other security levels as well as set names, passwords, and security
levels for other users. A superuser is usually the network element administrator. See also Retrieve user, Maintenance user, and
Provisioning user.
T
T1
T1 transmits DS-1-formatted data at 1.544 Mbps through the telephone-switching network using AMI or B8ZS coding. See
also AMI, B8ZS, and DS-1.
Tag
Identification information, including a number plus other information.
TDM
Time Division Multiplexing. Allocates bandwidth on a single wire for information from multiple channels based on
preassigned time slots. Bandwidth is allocated to each channel regardless of whether the station has data to transmit.
Telcordia
Telcordia Technologies, Inc., formerly named Bellcore. Eighty percent of the U.S. telecommunications network depends on
software invented, developed, implemented, or maintained by Telcordia.
TID
Target Identifier. Identifies the particular network element (in this case, the ONS 15454) where each TL1 command is directed.
The TID is a unique name given to each system at installation.
TLS
Transparent LAN Service. Provides private network service across a SONET backbone.