[SOLVED] Ethernet splitter adaptor used in reverse?

Cuss_ed

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Aug 10, 2019
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I have an ISP service plan of 2Gig.
I have a modem router with LAN ports of 1G each.
PC has a 2.5Gig Ethernet port.
So, can I run two cables from the modem, through an Ethernet splitter (2 to 1), and into my PC's single 2.5Gig Ethernet port?
My intention is obviously to take advantage of the bandwidth without having to spend, at present, a couple hundred dollars on a faster modem.
Will this work? Are these adaptors bi-directional? Will the signal be... intact (for want of a better word).
Am I considering a folly with a potentially damaging outcome? I'd hate to blow the faster Ethernet port on a new board.
Any advice would be appreciated.
Thanks in advance.
 
Solution
I have an ISP service plan of 2Gig.
I have a modem router with LAN ports of 1G each.
PC has a 2.5Gig Ethernet port.
So, can I run two cables from the modem, through an Ethernet splitter (2 to 1), and into my PC's single 2.5Gig Ethernet port?
My intention is obviously to take advantage of the bandwidth without having to spend, at present, a couple hundred dollars on a faster modem.
Will this work? Are these adaptors bi-directional? Will the signal be... intact (for want of a better word).
Am I considering a folly with a potentially damaging outcome? I'd hate to blow the faster Ethernet port on a new board.
Any advice would be appreciated.
Thanks in advance.
No you can't do that. Gigabit requires all 8 wires in an ethernet cable...

kanewolf

Titan
Moderator
I have an ISP service plan of 2Gig.
I have a modem router with LAN ports of 1G each.
PC has a 2.5Gig Ethernet port.
So, can I run two cables from the modem, through an Ethernet splitter (2 to 1), and into my PC's single 2.5Gig Ethernet port?
My intention is obviously to take advantage of the bandwidth without having to spend, at present, a couple hundred dollars on a faster modem.
Will this work? Are these adaptors bi-directional? Will the signal be... intact (for want of a better word).
Am I considering a folly with a potentially damaging outcome? I'd hate to blow the faster Ethernet port on a new board.
Any advice would be appreciated.
Thanks in advance.
No you can't do that. Gigabit requires all 8 wires in an ethernet cable. A 2-1 "splitter" works by creating two 100Mb links using 4 wires for each 100Mb connection.
You will have to find a switch or modem that has ports that support greater than 1Gb.
 
Solution
Feb 13, 2019
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So the ISP provided modem/router only has 1G LAN ports? Does it support link aggregation? If it supports LAG you can get an 802.3bz switch that also supports LAG to tandem two ports from the modem/router and then plug your PC into just one port on the switch. My hunch is that this modem/router does not support LAG nevermind that 802.3bz is typically only available in 10G switches which are still pretty expensive.
 

kanewolf

Titan
Moderator
So the ISP provided modem/router only has 1G LAN ports? Does it support link aggregation? If it supports LAG you can get an 802.3bz switch that also supports LAG to tandem two ports from the modem/router and then plug your PC into just one port on the switch. My hunch is that this modem/router does not support LAG nevermind that 802.3bz is typically only available in 10G switches which are still pretty expensive.
The OP original thread has more background -- https://forums.tomshardware.com/threads/ethernet-port-setup-via-bios.3552703/
Since you know very little about the modem/router it is very difficult for us to provide definitive help.
LAG would be the most common method of providing greater than 1Gb from a modem. You would need to configure that in the modem and a new switch. That switch would also need 1/2.5/5 Gb port(s) to connect your PC.
 

Cuss_ed

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Aug 10, 2019
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No you can't do that. Gigabit requires all 8 wires in an ethernet cable. A 2-1 "splitter" works by creating two 100Mb links using 4 wires for each 100Mb connection.
You will have to find a switch or modem that has ports that support greater than 1Gb.

Thanks yours reply.
Ok. So I'd be 'introducing' a limitation. There's a lesson learned.
Thanks for the concise explanation.
 

Cuss_ed

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Aug 10, 2019
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Thanks for your help people. LAG's a great idea and it parallels my thinking but as stated above without more info re. modem, my options are limited. I saw some snaps of the modem Settings / config last night and yes, you guess correct, it's in Japanese and my likelihood of getting a clear translation and locating a possible setting for bundling is highly unlikely.
I was hoping for a workaround but it looks like it's 1G (which personally I think is pretty good) for the time being until a hardware or Plan upgrade (they have 10G available. yes it boggles the mind).
Thank you again.
 
Last edited:
I have an ISP service plan of 2Gig.
I have a modem router with LAN ports of 1G each.
PC has a 2.5Gig Ethernet port.
So, can I run two cables from the modem, through an Ethernet splitter (2 to 1), and into my PC's single 2.5Gig Ethernet port?
My intention is obviously to take advantage of the bandwidth without having to spend, at present, a couple hundred dollars on a faster modem.
Will this work? Are these adaptors bi-directional? Will the signal be... intact (for want of a better word).
Am I considering a folly with a potentially damaging outcome? I'd hate to blow the faster Ethernet port on a new board.
Any advice would be appreciated.
Thanks in advance.

From the sound of the question, you are thinking of taking two ports from the 1 gig router, then merging them into one 2gb stream to your single network card? No, you can't do that. You are limited to the port speed on the router, the slowest link in the chain is the speed you will get.

I don't see you getting that much speed from any site you connect to also. I have FIOS gigabit connection and my actual speeds with downloads and web sites is much less.
 

Cuss_ed

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Aug 10, 2019
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From the sound of the question, you are thinking of taking two ports from the 1 gig router, then merging them into one 2gb stream to your single network card? No, you can't do that. You are limited to the port speed on the router, the slowest link in the chain is the speed you will get.

I don't see you getting that much speed from any site you connect to also. I have FIOS gigabit connection and my actual speeds with downloads and web sites is much less.

Thank's your reply.
Yes that was my intention.
2 to 1 with same speed but two streams of data to hopefully pickup extra bandw.
No matter. As you say, the likelihood of actually profiting here is slim at present due to site and server limitations.
Thanks again.
 
Thank's your reply.
Yes that was my intention.
2 to 1 with same speed but two streams of data to hopefully pickup extra bandw.
No matter. As you say, the likelihood of actually profiting here is slim at present due to site and server limitations.
Thanks again.

Network connections don't work that way, you can't just combine them like a water hose to get double the speed from two links. There is a thing called network card teaming when you can take two separate connections and then use two cards to possibly get some extra speed but you need two separate connections from the switch to the dual network cards, not one cable with a splitter.
 

Cuss_ed

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Aug 10, 2019
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Network connections don't work that way, you can't just combine them like a water hose to get double the speed from two links. There is a thing called network card teaming when you can take two separate connections and then use two cards to possibly get some extra speed but you need two separate connections from the switch to the dual network cards, not one cable with a splitter.

Thanks.
I think that particular argument has already been resolved.
Thanks again.