Superloop Gigabit Plan Stuck at 100 Mbps: the Router's LAN Port Was the Bottleneck (Waterloo)

Student · WaterlooSuperloop 1000MStuck at 100 MbpsFast Ethernet LAN portSecond-hand routerFixed to ~920M wired

A student in Waterloo had signed up for a Superloop gigabit (1000Mbps) plan, but every speed test topped out around 100Mbps. They assumed the provider was throttling them. We brought our own router and cables to test link by link on-site — and the plan turned out to be fine. The bottleneck was a second-hand router whose LAN port (and cable) only ran at 100 Mbps.

Wired speed · before vs after

Before

~100 Mbps

After

~920 Mbps

9×faster on the same Superloop gigabit line — nothing changed on the plan, only the router and the port.

The trap: a gigabit plan does not mean gigabit at your device

Where the speed was lost · the weakest link

NBN line

1000

→

Modem/ONT

1000

→

Gigabit cable

1000

→

Router LAN

100

Bottleneck

→

Your device

~100

A connection is only as fast as its slowest link. The plan, the modem and the modem-to-router cable were all gigabit — but this second-hand router's LAN port maxed out at 100 Mbps (Fast Ethernet), so every device behind it was capped at ~100. A 100M patch cable would do the same thing.

People see “1000Mbps” on the plan and assume every device gets it. But the speed you actually get is set by the slowest link in the chain — the line, the modem, every cable, the router’s ports, and the device’s own network card. Here the Superloop line, the modem and the modem-to-router cable were all gigabit. The one weak link was the router: a second-hand unit bought on Xiaohongshu whose LAN port was 100M Fast Ethernet, paired with a 100M patch cable. No plan upgrade could ever get past that 100M ceiling.

How we isolated it on-site

Wired laptop straight into the router

LAN port tested ~100 Mbps

Speed-tested WiFi on 2.4G and 5G

Both ~100 Mbps too

Checked the modem-to-router cable

Cable was gigabit → router at fault

Swapped in a gigabit-capable router

Wired hit ~1000 Mbps

Wired the bedroom port to the desk

Bedroom wired ~920 Mbps

The method is simple: test each link with gear you know is good, and change one thing at a time.

Wired a laptop straight into the router — still ~100M, so it was not just WiFi.
Tested WiFi on both 2.4G and 5G — also ~100M, pointing away from the wireless side.
Confirmed the modem-to-router cable was gigabit — so the line and cabling were fine, leaving the router.
Swapped in our own gigabit-capable router — wired speed jumped to ~1000M, proving the old router was the cap.
Wired the bedroom wall port to the desk and measured ~920M for a stable, low-latency connection.

100M port vs gigabit port: how to tell before you buy

100M port vs gigabit port · how to tell

	Fast Ethernet (100M)	Gigabit (1000M)
Max speed	100 Mbps	1000 Mbps
Standard	100BASE-TX	1000BASE-T
Often on	Cheap / old / second-hand routers; old Cat5 cables	Modern routers; Cat5e / Cat6 cables
How to check	Read the router’s spec sheet, look for “Gigabit” on the port silkscreen, or check the negotiated link speed in the router admin page. Test wired, not WiFi, to rule the port in or out.

This trap is common with cheap or second-hand routers. Before you buy, check the port speed — not just the WiFi standard.

Read the spec sheet for “Gigabit” / 1000BASE-T LAN ports.
Use Cat5e or Cat6 patch cables, not old Cat5.
Always test wired (not WiFi) to prove whether a port is the limit.

Result

Root cause: the second-hand router’s 100M Fast Ethernet LAN port (and a 100M cable), not Superloop. On a gigabit-capable router the same line delivered ~920 Mbps wired to the desk — a 9× jump with no plan change.

NBN slow speed troubleshooting What is FTTP fibre TP-Link routers Superloop guide Waterloo service area

Superloop Gigabit Plan Stuck at 100 Mbps: the Router's LAN Port Was the Bottleneck (Waterloo)

The trap: a gigabit plan does not mean gigabit at your device

How we isolated it on-site

100M port vs gigabit port: how to tell before you buy

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