What Is the Relationship Between the LOF and LOS Alarms?

How to detect LOF and LOS alarms and what is the relationship between these two alarms? What alarm is generated if optical fibers are removed when the Huawei MA5606T or MA5652G serves as an Huawei ONU?

LOF indicates loss of frame. When such an alarm is generated, the ONU can receive optical signals. LOS indicates loss of signal. When such an alarm is generated, the ONU fails to receive optical signals. The mechanisms of detecting LOFi and LOSi alarms are as follows:

• LOFi: If four consecutive frames of an OLT fail to locate an upstream frame of an ONU, the LOFi alarm is generated and the ONU goes offline.
• LOSi: If four consecutive frames of an OLT MA5600T fail to receive an upstream optical signal of an ONU, the LOFi alarm is generated and the ONU goes offline.

The relationship between the LOF and LOS alarms is as follows:

• Use an optical attenuator to test the ATM 155/622 Mbit/s optical port and increase the attenuation gradually. It is found that the alarm status changes as follows: normal -> SD -> LOF -> LOS. This indicates that after LOF is generated, if the attenuation is increased further, no optical signal is received and LOS is generated. If an optical fiber is removed, LOF may be generated first and then LOS, which is related to the alarm detection mechanism. The LOSi, LOFi, and LCDGi alarms are detected in the time window mode. In the first several detections, if the time window detects the threshold for frame losing, the LOFi alarm will be generated.
• If the PON line generates an LOF alarm, LOS will not be generated. This is because the PON port uses the time division system. If an LOF alarm is generated, the ONT goes offline and then the OLT does not assign the timeslot (bandwidth) to the ONU. Therefore, the OLT does not detect whether the ONT transmits upstream optical signals and an LOS alarm is not generated.
• If LOS is generated, LOF/SD will be suppressed. This is because LOS is the alarm of the highest severity.

When the MA5606T and MA5652G serve as an ONU MA5628 and the optical patch is normal, LOS is generated when an optical fiber is removed.

Problems to install N2000 clients in windows Vista

Issue Description

When you are in the process to install the software client N2000 V200R010 in a PC with the operating system Windows Vista the installation was stopped in the 80% of the installation process and the program don't respond. 

Alarm Information

The process of installation is stopped and the program doesn't respond.

Handling Process

To solve this problem was necessary go to internet and from the SUN web page download the jre-6u3-windows-i586-p-s.exe version of Virtual machine with this version the compatibility with windows vista and n2000 V200R010 client works normally.

Root Cause

When you are working with windows vista the java virtual machine that comes installed in the operating system is not compatible with the client software of the N2000 V200R010.

More Related:

iManager U2000 Single-Server System Software Installation Guide

Huawei Low-end Switches Upgrade The APP System

S5720-36C-EI-28S-AC

S5720-50X-EI-46S-AC

Huawei MA5800 Alarms and Events Handling

FAQs of Document Use When Handling Huawei MA5800 Alarms and Events 

This alarm and reference document, if used flexibly, can help you to rectify the faults quickly, thus improving maintenance efficiency and facilitating the management of alarms and events in the system.

Q1: How to enter the special CLI mode

A1: The following considers the FAN mode as an example to describe how to enter the FAN mode:

1. Click a command in the steps.
   
   
2. In the interface that is displayed, you can see the mode of the command. The User Guide describes how to enter this mode.

Q2: Why is the recovery alarm not displayed after the fault is rectified

A2: The following situations may occur:

• This alarm is an ADMC alarm caused by an ADMC fault. After the ADMC fault is rectified, the system does not generate a recovery alarm. Therefore, manual operations are needed. You can run the alarm active clear command to clear the alarms that are not recovered in the system.
• The system checks the faults periodically. The system generates a recovery alarm only after detecting that the faults are rectified.

Q3: How to search for an alarm or event in the document

A3: You can follow one of the following two methods to search for an alarm or event.

• Search for an alarm or event according to the alarm ID or the event ID.
• Search for an alarm or event according to the name of the alarm or event.

More related:

MA5600T Backup Redundant of Configuration Smart Link

P2P Access: Configuring FTTH Service

8-port GPON OLT Interface board H805GPBD

H805GPBD is a 8-port GPON OLT MA5603T MA5600T MA5608T Interface Board. It works with the optical network terminal (ONT) to provide GPON access service.


Working Principle

The basic working principle of the H805GPBD board is as follows:
The control module loads the board software, controls the running of the board, and
manages the board.
The switching module aggregates the signals from eight GPON ports.
The interface module converts between GPON signals and Ethernet packets.
The power module supplies power to other functional modules of the board.
The clock module provides the working clock for other functional modules of the board.

Huawei HG8010H an Intelligent bridging-type ONT

Huawei EchoLife HG8010H optical network terminal (ONT) is a indoor optical network terminal in Huawei FTTx solution. By using GPON technology, ultra-broadband access is provided for home and SOHO users. The HG8010H provides one 10/100/1000M Base-T Ethernet port for connecting to a home gateway. The home gateway then can be connected to a PC, Mobile Terminal, STB, or Video phone to provide high-speed data, video services and WiFi.

Huawei HG8010H Interface Parameters

GPON Port

Class B+

Receiver sensitivity: -27dBm

Wavelength blocking filter (WBF)

Flexible mapping between GEM Port and TCONT

GPON: consistent with the SN or password authentication defined in G.984.3

Bi-direcetional FEC

SR-DBA and NSR-DBA

Ethernet port

Ethernet port-based VLAN tags and tag removal

1:1 VLAN, N:1 VLAN, or VLAN transparent transmission

QinQ VLAN

Limit on the number of learned MAC address

MAC address learning

Transparent transmission of IPv6 packets at Layer 2

Huawei DWDM Flexible Bandwidth Utilization Based on ODUflex

Huawei OptiX OSN 8800 supports the optical data unit flexible (ODUflex) feature. This feature enables the OptiX OSN 8800 to adapt itself to various services, such as video, storage, and data services as well as future IP services.

Transport of Generic CBR Signals

ODUflex can be used to transmit constant bit rate (CBR) services on an optical transport network (OTN). The services whose CBRs are higher than 2.48832 Gbit/s are mapped to an ODUflex (CBR) container in bit synchronization mode. Functions such as end-to-end performance monitoring and protection switching are feasible on the ODUflex (CBR) container. The overheads and monitoring management modes of ODUflex services and traditional ODUk are the same.

below shows how ODUflex is used to transport generic CBR signals. An FC400 service occupies four ODTUk timeslots and is mapped to an ODUflex container. A 3G-SDI service occupies three ODTUk timeslots and is mapped to an ODUflex container. Each ODTUk timeslots provides 1.25 Gbit/s bandwidth. The FC400 and 3G-SDI services share the same OTU2 wavelength.

ODU2 is used to transport generic CBR signals. The FC400 and 3G-SDI services are mapped to different ODU2 containers. Therefore they occupy different OTU2 wavelengths.

Transport of VBR Packet Services

ODUflex can also be used to transport variable bit rate (VBR) packet services to address the requirements of transporting packet services running at VBRs. Since packet services run at VBRs, ITU-T has defined ODUflex(GFP) signals for transporting packet services over an OTN network. The ODUflex(GFP) signals are mapped differently from CBR client signals and use different bit rates as the ODUflex(CBR) signals. The ODUflex(GFP) signals are mapped using the GFP-F method and the bit rate for the signals is defined to about N x 1.25 Gbit/s, where N represents the number of the ODTUk timeslots.

In this application, ODUflex ensures that resilient packet services are correctly transmitted over Huawei OTN network. For example, ODUflex can be used in a 3G backhaul bearer network or an enterprise/bank packet quality private line application. ODUflex(GFP) can flexibly resize the bandwidth based on the bandwidth required by packet services and therefore adapts to flexible changes in service bandwidth and ensures high-quality service transmission.

Huawei S6700 Series Switch Applications

Data Centers
Huawei S6700 can be used in Huawei's sustainable data center solution, which offers four major advantages: evolution, availability, pooling, and visualization.

As shown in the following figure, the S9700 Terabit routing switches function as core switches in a data center and use firewall and load balancer boards to ensure security and load balancing. The S6700 functions as an access switch and provides high-density 10GE ports to connect to 10G servers.

Campus Networks
The S6700 like S6700-48-EI can function as a core switch on a campus network and provide high-density line-speed 10GE ports, rich service features, and comprehensive security mechanisms. This makes Huawei S6700 a cost-effective option.