After 30 add/drops you may lose too much power. There is a minimum 1.4dB per passthru and 1.3dB per add/drop, 3.5dB per MUX at the ends. With these SFP+ modules: https://www.fs.com/products/31238.html it looks like you would have a 19-20 dB budget to work with. You may be able to get 10 add/drops without amplification. But they have amps too: https://www.fs.com/products/72284.html I'd definitely contact sales and talk to one of their engineers so they can design a complete working solution for you. Are you sure you can't pull more fiber? It may be cheaper. On Wed, Feb 26, 2020 at 07:42:23AM -0600, Mike Hammett wrote:
DWDM can be done fairly cheap. Some combination of MUXes and OADM modules along the way. One possible solution is:
First floor: https://www.fs.com/products/35887.html Every floor between: https://www.fs.com/products/70427.html Top floor: https://www.fs.com/products/35887.html
Every floor gets 10G to aggregation switches on the top floor and bottom floor. The aggregation switches directly connect via the second pair.
----- Mike Hammett Intelligent Computing Solutions
Midwest Internet Exchange
The Brothers WISP
----- Original Message -----
From: "Ryan Hamel" <ryan@rkhtech.org> To: "Bradley Burch" <bradley@wifastnetworks.com> Cc: nanog@nanog.org Sent: Tuesday, February 25, 2020 10:45:05 PM Subject: Re: Hi-Rise Building Fiber Suggestions
How would that work to solve Norman's problem? That sounds like a lot of money spending, and setup time, for nothing.
Ryan
On Feb 25 2020, at 8:21 pm, Bradley Burch <bradley@wifastnetworks.com> wrote:
Should consider DWDM or GPON and in those look at passive optical technologies that can benefit the project.
<blockquote>
On Feb 25, 2020, at 9:33 PM, Norman Jester <nj@jester.mx> wrote:
I’m in the process of choosing hardware for a 30 story building. If anyone has experience with this I’d appreciate any tips.
There are two fiber pairs running up the building riser. I need to put a POE switch on each floor using this fiber.
The idea is to cut the fiber at each floor and insert a switch and daisy chain the switches together using one pair, and using the other pair as the failover side of the ring going back to the source so if one device fails it doesn’t take the whole string down.
The problem here is how many switches can be strung together and I would not try more than 3 to 5. This is not something I typically do (stacking switches). I have fears of STP and/or RSTP issue stacking past Ethernet switch to switch limits (if they still exist??)
Is there a device with a similar protocol as the old 3com (now HP IDF) stacking capability via fiber?
I’d like to use something inexpensive as its to power ubiquiti wifi on each floor. Ideally if you know something I don’t about ubiquiti switches that can do this I’d appreciate knowing.
Norman
</blockquote>