I’ve been asked these questions four times in about a week’s time.
Let’s nip this in the bud.
What’s with the PTP 820C 4+0 XPIC BOM?
What’s with all of the fiber gear?
What’s with the protection cables?
We need to enhance LINKPlanner.
Until then, here are the questions you have to ask when you’re designing a PTP 820C 4+0 link:
Here are the three link types that you’ll probably use:
Short Link, combine traffic at the shack, out-of-band management, PoE
PoE via ETH1, copper SFP module in ETH2, PoE injector, and three copper Ethernet cables per PTP 820C box. Four surge suppressors per PTP 820C box, two at the top of the tower, and two at the bottom of the tower. (Remember that ETH1 and PoE injector have built-in surge suppression.)
So in total, that’s four (4) copper SFP modules, four (4) PoE injectors, twelve (12) copper Ethernet cables, four PTP 820C boxes, and sixteen (16) surge suppressors for the link. Yes, that’s a lot of equipment, but the link will carry more than 4 Gbps!
Long link, MC-ABC, combine traffic at the shack, out-of-band management, external DC
External DC cable, fiber SFP module in ETH2, MNG copper Ethernet cable, external DC power supply, and one fiber Ethernet cable per PTP 820C box. Two (2) surge suppressors per PTP 820C box, for the MNG cable, one at the top of the tower, and one at the bottom of the tower.
So in total, that’s four (4) fiber SFP modules, four (4) MNG Ethernet cables, four (4) fiber Ethernet cables, four (4) PTP 820C boxes, eight (8) surge suppressors, and lots of external DC cabling for the link. Note that you probably also need SFP modules for your external switch.
Long link, MC-ABC, combine traffic at the shack, out-of-band management, PoE
PoE via ETH1, MNG copper Ethernet cable, PoE injector, and two copper Ethernet cables per PTP 820C box. Two surge suppressors per PTP 820C box, for the MNG cable, one at the top of the tower, and one at the bottom of the tower.
So in total, that’s four (4) PoE injectors, four (4) MNG Ethernet cables, four (4) copper Ethernet cables, four (4) PTP 820C boxes, eight (8) surge suppressors. Note that you probably also need SFP modules for your external switch.
If you’re VLAN, LAG, etc. savvy, you can probably easily configure your switches to support in-band management for the two long link options. (In-band management eliminates the need for the surge suppressors and management cables.)
If you’re exceptionally network savvy and you’re willing to configure both your external switches and your PTP 820C boxes with MMA and ASP (Mate Management Access and Automatic State Propagation), you can use in-band management for the short link. (Again, in-band management eliminates the need for the surge suppressors and management cables.)
Bring on the corrections, observations, and questions!
In my opinion, the most common use of 4+0 (2x2+0) would be for high capacity. Since LINKPlanner assumes the "long link" scenario a few manual changes are required to adjust the autogenerated BOM for the "short link" high throughput scenario. I've also attached a full 11GHz PTP820C Wideband 2x2+0 XPIC (aka 4+0) BOM for reference.
Basically, the following changes are needed:
- Delete all fiber runs and parts
- Remove the DC connector and DC cables unless external power is desired
- Add a PoE injector per PTP820C unless external power is desired
- Replace fiber SFP with copper SFP
- Add sufficient Cat5 cable drums for three Cat5 cables per PTP820C radio - the three runs are for ETH1, ETH2, and MGT
- Add ALPU-F140 non-Cambium surge suppressors for non-powered Cat5 runs
Once those changes are made you'll have a correct BOM for your deployment!
If fiber runs are desired over copper runs then external power will be required and the PTP820C will need to be special ordered so that ETH3 can be used for data. ETH3 is reserved for MIMO on standard PTP820C radios and for two fiber runs per PTP820C in this scenario both SFP ports (ETH2 and ETH3 ports) would be used. Cat5 cable will still be required for out of band management.
If narrowband radios are used instead of wideband radios then the total throughput will be under a gigabit. That will preclude the need for a second data run and it will also allow for in-band management since there is only one data run. MC-ABC (physical layer link aggregation) will then be used instead of adding a second data run and only one Cat5 run will be required for PoE, data, and in-band management. This would be the simplest implementation. The difference from the bullet points above then would be to add MC-ABC and delete the second GE port license, delete SFP's, and only provision Cat5 cable for one run per PTP820C.