Hi, everybody!
This is the last article about problems with slow internet and how we can fix it in the FTTH PON networks.
As I show in the last article, in the next table, we can see all problems with slow internet access. The problem can be the user`s device (router, switch, PC, etc), ONT, OLT, and upper-layer device (BRAS, aggregation switch, router).
Today I will explain problems with OLT and upper-layer devices.
|
User`s devices |
Problems with PC |
|
Problems with user`s network devices |
|
|
ONT |
Problems with the hardware |
|
Problems with wireless network |
|
|
OLT |
Problems with the hardware |
|
Problems with configuration on the OLT |
|
|
Problems with packet loss and unknown traffic |
|
|
Upper-layer device |
Problems with the limited rate, discard packets and delay |
1. Problems with the hardware of the OLT
Very rarely, OLT can have hardware problems. If the problem is with all ONTs on one PON port, the problem can be SFP or slot for SFP. If there are problems with a large number of ONTs on all PON ports of one GPON board. The problem should be looked for on the GPON board or slot for the GPON board. And the end, if there are problems with all ONTs on one OLT, the problem may be the OLT chassis.
In these cases, we have to change SFP, slot, GPON board, or chassis. After that, we will fix the problems.
2. Problems with configuration on the OLT
If the hardware of OLT is ok, the problem may be in the configuration on the OLT. This is a situation where all ONTs on OLT have problems with slow internet traffic. OLT is configured so that the speed of the internet is limited and is lower than the current user requirements.
We can fix this problem, when we change configuration – increase the internet speed.
Figure 1. OLT EA5800-X7
(https://e.huawei.com/en/products/enterprise-transmission-access/access/olt/ea5800)
3. Problems with packet loss and unknown traffic
If a large amount of traffic occurs on the upstream port on the control card, it will lead to packet loss. Problems with slow internet service will occur with all ONTs on OLT.
4. Problems with the limited rate, discard packets, and delay
If problems with slow internet service occur on all ONTs on several different OLTs, the problem is in the upper-layer device. These include BRAS, aggregation switch or router, and UTP or optical cables.
A similar problem as with OLT configuration. Speed on the BRAS is limited and internet speed is less than current needs. The problem is solved by changing the configuration to BRAS, we need to increase the internet speed.
Other problems are discarding user packages or long delays. We have to check the configuration on the upper-layer device and cables.
Thank you!
