Introduction

My home is equipped with an internet connection from my ISP. It uses one router that emits wi-fi signal. It transmitted at least 5 devices. However, the signal coverage is not optimal. There are some areas that are not covered by the wi-fi signal. Therefore, I decided to expand my network so that these unreachable areas can enjoy internet connection. To do this, I need to set up a new route.

Objective(s)

1. Expand home network so that more areas in my house is covered by the wi-fi signal.

Preparations

Network Diagram

The idea of this expansion is simple. Add a new router and connect it to the main router. The new router will take a role as a switch rather than a router.

flowchart TB
    ISP((ISP))
    R1[(R1 192.168.18.1)]
    R2[(R2 192.168.18.250)]
    D1
    D2
    D3
    D4
    D5
    D6
    D7
    D8

    R1 --- ISP
    D1-->R1
    D2-->R1
    D3-->R1
    D4-->R1
    D5-->R1
    D6-->R1
    R2-->|192.168.18.1|R1
    D7-->R2
    D8-->R2

Tools

I will be needing some tools and preparations to achieve a broader wi-fi signal coverage. Below, I listed the tools needed.

Measurement

This section primarily discusses how I measured the LAN cable length needed for this project. I divided the measurements by room. There are 4 rooms:

• House 1
• Garage
• The “Bridge” (that separates house 1 and house 2)
• House 2

This photo showcases my field note on the measurement process. I made some confusion and mistake during the formulation part so I had to prove that my model formula has a high accuracy estimation.

House 1

I grabbed my tape measurement and started measuring from the main router. The picture below illustrates the lines of measurement. All measurements are in cm except for the final measurement (meter).

x1 <- 15
x2 <- 15
x3 <- 37
x4 <- 17
x5 <- 160
x6 <- 159
x7 <- 159
x8 <- 49
x9 <- 112
x10 <- 14

Garage

My line will be following the previous network engineer’s work.

x11 <- 122
x12 <- 247
x13 <- 449

The “Bridge”

There is a part where I was unable to fully survey the line (see x14). I assumed there is no 90 degree turn inside. The tile in House 2 is $ 40 \times 40 $

tile <- 40
x14 <- 40
x15 <- 2*20 + 2*60 + 59 + tile*3 + 33
x16 <- 76
x17 <- 1
x18 <- 87
x19 <- 50

House 2

h_router <- 5
l_router <- 10
x20 <- 6 + 11
x21 <- 61
x22 <- tile + tile/2
x23 <- 33 + tile*5 + tile/2
x24 <- h_router + 1
x25 <- l_router/2
x26 <- 2

The Bend Radius

I was wondering whether there is a rule of thumb when bending cables in $ 90 ^{\circ} $ turns. So, I consulted to some literatures and found that $ 90^{\circ} $ turn follows the following formula:

Final Cable Length

The final cable length needed for this setup can be found by using simple arithmatics. I formulated the calculation using the following formula:

Since it is rare to see online shops selling custom LAN cable length, I decided to round up the cable length to 30 meters.

##