What does a T1 Yellow alarm indicate?

Description: An incoming yellow alarm indicates that the T1 network element connected to the T1 interface has a problem with the signal it is receiving from the T1 interface.

What is a T1 blue alarm?

The T1 will send AIS (also known as a Blue alarm) when there is a disruption in the upstream transport path. This signal is all 1’s in the payload *AND* framing bits.

What is remote alarm indication?

Receive Remote Alarm Indication (Yellow) A receive remote alarm indication (RAI) means the far end equipment has a problem with the signal it is receiving from the upstream equipment. The failure is cleared if the Yellow alarm signal pattern does not occur in ten contiguous 16-bit signal pattern intervals.

What is AIS alarm in E1?

The AIS is an. unframed, all-ones signal transmitted on the E1 line.1. Network equipment transmits the AIS alarm instead of the “normal” signal when there is a Loss Of Signal (LOS) and Loss Of Framing (LOF) condition at the receive side of the equipment.

What is the difference between an indication and an alarm?

ECDIS provides a large number alarms and indications. An alarm in this context means an alarm or alarm system which announces by audible means, or audible and visual means, a condition requiring attention. An indicator is a visual indication giving information about the condition of a system or equipment.

What is the difference between T1 and DS1?

DS1 is a digital signal level that is part of a standardized hierarchy or building blocks of digital services for TDM (Time Division Multiplexing) digital lines. A T1 line multiplexes or aggregates 24 of these DS0 channels into a DS1 with a total bandwidth of 1.536 Mbps. But a T1 line runs at 1.544 Mbps.

What causes frame alarm loss?

Three of the conditions that cause alarms are loss of frame alignment (LFA), loss of multi-frame alignment (LFMA), and loss of signal (LOS). The LOS may occur when a cable is not plugged in or the far end equipment, which is the source of the signal, is out of service.

What is ECDIS alarm parameters?

ECDIS alarm parameters To ensure the mariner is fully aware of the depth of surrounding water the display must show spot soundings and isolated dangers. ‘No-go’ areas can also be displayed, using the ‘Add Info’ function. Safety Depth: Is to be set to at least the maximum dynamic draft, plus 10% of static draft.

What Solas regulation is alarm system?

As per the SOLAS Chapter XI regulation XI-2/5, all ships shall be provided with a ship security alert system.

How many T1 are in a DS-1?

24
A T1 line multiplexes or aggregates 24 of these DS0 channels into a DS1 with a total bandwidth of 1.536 Mbps.

What does a receive AIS signal on T1 mean?

After each step, run the show controller t1 command to see if any alarms occur. A receive (Rx) alarm indication signal (AIS) means there is an alarm occurring on the line upstream from the equipment that is connected to the port.

How to correct T1 alarm from sending remote alarms?

To correct the transmitter from sending remote alarms, complete the following steps: Ensure the framing format configured on the port matches the framing format of the line. If not, change the framing format on the controller to match the format of the line. Check the settings at the remote end and ensure that they match your port settings.

When does a Los / Oof condition cause an AIS alarm?

When a data path is broken the first downstream device to detect this LOS/OOF condition sends an AIS-Alarm on down the line (2.5 seconds of an OOF condition will also cause the device to go into Red-Alarm and send a Yellow-Alarm back up the line). This AIS-Alarm consists of an unframed all ones signal sent to maintain transmission continuity.

When does an AIS alarm signal go off?

This AIS-Alarm consists of an unframed all ones signal sent to maintain transmission continuity. It is usually an indication of a physical layer problem. Occurs when the equipment detects a continuous OOF condition for 2.5 seconds. This alarm state is cleared when no OOF conditions occur for at least 1 second