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Field notes

Design decisions, written on site.

Practical notes that start from a field question and end at a design decision: what the numbers mean, which table to use, and which model or product family to check.

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12 notes7 topic guides5 field notes

Latest notes

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City at night with connected infrastructure, the public right of way where aerial and underground fibre routes are built

Outside plant

Aerial vs Underground Fibre: What the Route Costs Your PON

10 min read

Outdoor utility poles and network infrastructure at dusk

CCTV power design

CCTV Pole Power Design Checklist: PoE, Extenders and PoF

9 min read

Project types

Start where your project starts.

Each note is self-contained. The technical library covers the individual calculations; these notes show how the calculations fit a real site.

12 notes
PoE switches and patch panels inside a network cabinetFeatured field note

PoE switching

PoE Switch Selection Guide: 8 vs 24 Ports, Budget and Uplinks

Choose a PoE switch by the powered load, not the port count: 8 vs 24 ports, 802.3af/at/bt, the shared budget, the 100 m limit and the uplinks that decide the design.

Project type
PoE switching
Tables
2
Reading time
9 min read

What this note covers

  • Why does port count alone fail as a PoE switch specification?
  • How do you add up the PoE budget before choosing a switch?
  • 8-port or 24-port: which size fits the site?
Read the note

More field notes

All notes
City at night with connected infrastructure, the public right of way where aerial and underground fibre routes are built

Outside plant

Aerial vs Underground Fibre: What the Route Costs Your PON

Aerial and underground fibre differ by more than cost per foot: splice count, passive budget, split ratio and repair cost, with 2025 build figures.

November 9, 2026·10 min read·2 tables
Outdoor utility poles and network infrastructure at dusk

CCTV power design

CCTV Pole Power Design Checklist: PoE, Extenders and PoF

A field checklist for CCTV cameras on poles: the load list, the 100 m PoE channel, the 200 m PoF port, the 12 W budget, surge and earthing, and the handover record.

October 24, 2026·9 min read·4 tables
Hotel and smart building at night with connected systems

Hotel networks

Hotel All-Optical Network Planning: OLT, Room ONT and Ceiling APs

How to plan a hotel all-optical network: PON port count, room ONT selection, corridor APs over PoF, CATV and POTS on one fibre, VLANs and the 20 km / 1:64 optical budget.

October 24, 2026·10 min read·5 tables
Hybrid fibre and copper cable used for Power over Fiber

Cost engineering

PoE vs PoF: Installed Cost, Worked Example and Decision Table

A cost-engineering comparison of PoE and PoF: the cost lines that matter, a worked eight-camera example, hidden costs and a decision table for the last 100–200 m.

October 24, 2026·10 min read·5 tables
Fibre distribution rack with OLT, splitters and patch panels

FTTH engineering

FTTH Splitter Planning Field Notes: 1:32 vs 1:64 and the 3 dB Rule

Field notes on FTTH splitter planning: 16.5 dB vs 20.5 dB, connector and splice counts, the worst-case port, the 3 dB ageing margin and as-built measurements.

October 24, 2026·9 min read·5 tables
Fibre optic cables entering a metro network cabinet

PON standards

XGS-PON vs GPON vs EPON: What Changes in a Real Project

A project-level comparison of GPON, EPON, XGS-PON, XG-PON and 10G EPON: line rates, split ratios, optical budget, coexistence, ONU matching and migration sequence.

October 27, 2026·10 min read·2 tables
GPON OLT and ONU equipment on a network test bench

PON access

GPON OLT and ONU/ONT Explained: Ports, Split Ratio and Setup

How a GPON OLT and ONU/ONT work together: ports and uplinks, the 1:32 vs 1:64 split, the optical budget, ONU selection, registration and the commissioning record.

October 27, 2026·10 min read·2 tables
Cross-section of a hybrid cable with optical fibre and copper conductors

Power over Fiber

Power over Fiber Explained: Reach, 12 W Budget and When to Use It

How Power over Fiber works in practice: the hybrid cable, the 12 W port budget, voltage drop at 200 m, what fits on a port, when PoF beats PoE and when it does not.

October 27, 2026·10 min read·2 tables
Fibre optic strands carrying a red light signal

Optical transport

EDFA and 1550 nm Transmitter Guide: CATV Overlay Reach and Budget

How 1550 nm transmitters and EDFAs are sized for CATV overlay: direct vs external modulation, fibre loss, split loss, receiver input window and the commissioning record.

October 27, 2026·10 min read·2 tables
Technician installing network equipment at an outdoor site

Wireless

Outdoor Wireless Access Point: Power, Backhaul and Pole Design

How to plan an outdoor wireless access point: PoE vs PoF vs fibre plus local power, the 100 m and 200 m limits, backhaul, pole mounting, surge protection and the handover record.

October 27, 2026·10 min read·2 tables
Optical access equipment under test in a rack before an XGS-PON migration

PON migration

GPON to XGS-PON Migration: Coexistence and Cutover

Moving a live GPON estate to XGS-PON without rebuilding the ODN: the audit measurements, the reduced-band rule, the coexistence loss and the split ratio it forces, then cutover and records.

November 5, 2026·9 min read·5 tables

At a glance

All notes, one table.

12 notes
Field noteProject typeTablesReading timeKey topics
Aerial vs Underground Fibre: What the Route Costs Your PONOutside plant210 min readWhy does the construction method decide more than the OLT? · What does each method cost per foot, and per home passed?
CCTV Pole Power Design Checklist: PoE, Extenders and PoFCCTV power design49 min readWhat belongs in the pole load list before anyone chooses a cable? · How much power does a pole camera really draw?
Hotel All-Optical Network Planning: OLT, Room ONT and Ceiling APsHotel networks510 min readWhat does an all-optical hotel network replace? · How many PON ports does the hotel need?
PoE vs PoF: Installed Cost, Worked Example and Decision TableCost engineering510 min readWhy is the unit price the wrong basis for comparing PoE and PoF? · What goes into the installed cost of a PoE drop?
FTTH Splitter Planning Field Notes: 1:32 vs 1:64 and the 3 dB RuleFTTH engineering59 min readWhat do 1:32 and 1:64 really cost in optical dB? · Why must the worst-case port, not the average, set the split ratio?
PoE Switch Selection Guide: 8 vs 24 Ports, Budget and UplinksPoE switching29 min readWhy does port count alone fail as a PoE switch specification? · How do you add up the PoE budget before choosing a switch?
XGS-PON vs GPON vs EPON: What Changes in a Real ProjectPON standards210 min readWhat does each PON standard actually deliver? · Where does the bandwidth difference show up on site?
GPON OLT and ONU/ONT Explained: Ports, Split Ratio and SetupPON access210 min readWhat does a GPON OLT do that a switch does not? · What does the ONU/ONT do at the subscriber end?
Power over Fiber Explained: Reach, 12 W Budget and When to Use ItPower over Fiber210 min readWhat is Power over Fiber, in practical terms? · How much power actually reaches 200 m?
EDFA and 1550 nm Transmitter Guide: CATV Overlay Reach and BudgetOptical transport210 min readWhy use 1550 nm for CATV overlay and long transport? · Direct or external modulation: which transmitter fits?
Outdoor Wireless Access Point: Power, Backhaul and Pole DesignWireless210 min readWhat makes an outdoor access point different from an indoor AP? · PoE, PoF or local mains: which power path fits the pole?
GPON to XGS-PON Migration: Coexistence and CutoverPON migration59 min readWhat has to be true before a GPON estate can carry XGS-PON? · Which ODN measurements decide the migration?

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