1:1 uplink backup protection and ring protection scenarios in PON systems
Apart from a regular scheme with series of 1:N splitters in FDN, some networks, especially those with industrial grade for power, gas or electricity providers, require equipment and some network design skills to provide backup schemes for your PON network.
Theoretically there is a 3 ways to provide such kind of backups:
1. Protecting fiber damage – in this case 2:N type splitters are used and topologu could look like this:
Here we are protecting fiber link from OLT to optical splitter. Because naturally, if that strand get’s damaged, all ONU’s that are “hanging” on this splitter will immediately go down.
Now, if there’s an important customers at CPE side (who also naturally have only 1 fiber), then 2 fibers can be installed to their premises and then 2 PON (1+1) uplink EPON ONU’s need to be used.
Then network topology will look like this:
And another way to this is so called OLT protection. Like if one OLT get’s damaged, network get’s a feed from a standby OLT.
Then topology will look like this:
