Using Comcast 1Gbit service, quick question please

newls1

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SO I have the following hardware:

Motorola SB8600 modem (Docsis 3.1)
Asus AC3100 Router (pretty sure I can combine lan ports to get 2gb Lan)

How can I combine 2 1gb lan ports from router, to run into my desktop to see if my single lan connection is providing a bottleneck? Hope im describing this correctly or atleast making sense?! With my current setup ive been "Speedtesting" 940mb/s ever since ive had a 700Mb/s connection, then last year comcast did a free upgrade to 850mb/s and still getting the same bottleneck, so I upgraded my cat5e cables to cat 6 and still the same speed, now yesterday I got an email from comcast stating they did a free upgrade to 1gbit and im still getting 940-950Mb/s speeds (I think that is the limit for 1gb if im not mistaken) so im thinking ive been exceeding the limit of my 1gb lan port and want to seek help about combining 2 1gb lan ports and finally utilize my intel 2.5gb lan on my motherboard! HELP!!
Appreciate any feedback!
 
The SB8600 only has a single 1GbE port, so you'll never get faster than gig speeds out of it. You need to upgrade the modem to one with a 2.5GbE port first and then proceed to upgrade the rest of the equipment to support whatever slightly faster speeds Comcast gives you over 1GbE.
 
Link aggregation won't give you double the bandwidth from a single client. Connect two computers to the router and do a simultaneous speed test. Even a PC + a phone over WiFi would be enough to test your max speed.
 
so then whats the purpose of having a 1gb/s service then? I have no option to use all my available bandwidth? If my modem supports up to 4gb/s service, and my router and NIC's are 2.5gb capable, surely I can do something here to get all my bandwidth.. no?

EDIT**** So going into my modems firmware, I have the option for LAG.... I need to setup my router first before I bond these 2 LAN ports right? IS that what that window is telling me?

IMG_0372.jpg
 
You can use multiple devices, but no, a single device will be limited by its single LAN port speed. There may be some crazy workarounds to get a single PC to utilize bonded bandwidth, but nothing practical AFAIK.

The window just reminds you that you need the devices on both ends of the cables to support LAG and be set up to use it.
 
You're getting your bandwidth. 1Gbps service doesn't mean that you have 1Gbps of usable of bandwidth. It means the equipment has up to that limit. There is protocol and transport overhead and such that must be taken into consideration. 940Mbps is generally the usable data limit. 5 seconds with google could have saved some time as you're not the first person to ask and sadly won't be the last.

https://www.reddit.com/r/HomeNetwor...ck_question_why_do_most_gigabit_plans_cap_at/
 
First, I assume that you meant MB8600, not SB8600? There is no "SB8600". The "SB" was branding for "Surfboard", but those "Motorola Surfboard" modems were mare by Arris. The Motorola name is a brand name that has been passed around like a $2 whore over the years and a few years ago the licensing agreement with Arris expired. New "Motorola" modems (MB8600, etc) are now made by Zoom and they are, quite frankly, trash. Arris continued the Surfboard line of modems under their own name.

The MB8600 has 4 ethernet ports, but only two can be used for link aggregation. That doesn't matter in your case however because your Asus AC3100 Router only has one WAN port. You would need a router with 2 WAN ports also, that can also do link aggregation on those ports. The AC3100 supports link aggregation on the LAN ports (a pretty useless feature now with SMB 3.0+), but it does NOT support it on the WAN port, since there is only one...

stage_5_img.png

so then whats the purpose of having a 1gb/s service then? I have no option to use all my available bandwidth? If my modem supports up to 4gb/s service, and my router and NIC's are 2.5gb capable, surely I can do something here to get all my bandwidth.. no?

Well it's kind of a sad joke overall considering how restrictive monthly caps are on Comcast / Xfinity. So the only thing your extra speed is really doing is helping you hit your cap faster.

But there are ways to get more than 1Gb. You could get a modem AND a router (2 wan ports) that both support link aggregation. Or, you could get a modem with a 2.5GbE port and pair that with a router that has a 2.5GbE WAN port. Right now you have one of each... A modem with 2 1Gb ports and a Router with only one 2.5GbE port. So either replace your modem with a modem that can do 2.5GbE or get a router that has 2 WAN ports and can do link aggregation on those two ports.
 
You're getting your bandwidth. 1Gbps service doesn't mean that you have 1Gbps of usable of bandwidth. It means the equipment has up to that limit. There is protocol and transport overhead and such that must be taken into consideration. 940Mbps is generally the usable data limit. 5 seconds with google could have saved some time as you're not the first person to ask and sadly won't be the last.

https://www.reddit.com/r/HomeNetwor...ck_question_why_do_most_gigabit_plans_cap_at/
and sadly you didnt read my full question.... I know what the cap of 1gbs service is, thanks!
 
First, I assume that you meant MB8600, not SB8600? There is no "SB8600". The "SB" was branding for "Surfboard", but those "Motorola Surfboard" modems were mare by Arris. The Motorola name is a brand name that has been passed around like a $2 whore over the years and a few years ago the licensing agreement with Arris expired. New "Motorola" modems (MB8600, etc) are now made by Zoom and they are, quite frankly, trash. Arris continued the Surfboard line of modems under their own name.

The MB8600 has 4 ethernet ports, but only two can be used for link aggregation. That doesn't matter in your case however because your Asus AC3100 Router only has one WAN port. You would need a router with 2 WAN ports also, that can also do link aggregation on those ports. The AC3100 supports link aggregation on the LAN ports (a pretty useless feature now with SMB 3.0+), but it does NOT support it on the WAN port, since there is only one...

View attachment 405871



Well it's kind of a sad joke overall considering how restrictive monthly caps are on Comcast / Xfinity. So the only thing your extra speed is really doing is helping you hit your cap faster.

But there are ways to get more than 1Gb. You could get a modem AND a router (2 wan ports) that both support link aggregation. Or, you could get a modem with a 2.5GbE port and pair that with a router that has a 2.5GbE WAN port. Right now you have one of each... A modem with 2 1Gb ports and a Router with only one 2.5GbE port. So either replace your modem with a modem that can do 2.5GbE or get a router that has 2 WAN ports and can do link aggregation on those two ports.
and there's the answer, THANK YOU! Ill be replacing this router with one with 2 wan ports... Much appreciated. Can you recommend a router sub 250$??

**EDIT** Is this a good choice to obtain my goals? https://www.amazon.com/TP-Link-Archer-AX90-Wireless-High-Speed/dp/B08TGPTQ14/ref=sxin_13_pa_sp_search_thematic_sspa?cv_ct_cx=dual+wan+router&dchild=1&keywords=dual+wan+router&pd_rd_i=B08TGPTQ14&pd_rd_r=82e9c6a9-dfac-4b81-b8fd-02fb6df7a8f5&pd_rd_w=CwmC0&pd_rd_wg=4yuHi&pf_rd_p=f21da57e-06e4-46a5-9148-e2dea2e78384&pf_rd_r=0EZ7TPFXD63CZKS0CH6E&qid=1635014858&sr=1-4-a73d1c8c-2fd2-4f19-aa41-2df022bcb241-spons&spLa=ZW5jcnlwdGVkUXVhbGlmaWVyPUFOUVJYRFY3UzUwR0smZW5jcnlwdGVkSWQ9QTA4NjY2NTUyVTJIWjk4RlMySjU1JmVuY3J5cHRlZEFkSWQ9QTAxNzMyNjYzVEczQ1lRWE9XMk5HJndpZGdldE5hbWU9c3Bfc2VhcmNoX3RoZW1hdGljJmFjdGlvbj1jbGlja1JlZGlyZWN0JmRvTm90TG9nQ2xpY2s9dHJ1ZQ&th=1

OR... I can go get this right now at my local MC https://www.microcenter.com/product/636375/tp-link-ax3200-tri-band-wi-fi-6-router
 
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and sadly you didnt read my full question.... I know what the cap of 1gbs service is, thanks!
Then your question makes no sense. If you know what the connection limit is then nothing you do on the lan side is going to change that. You can pipe 10Gbps into the bridge but the upstream limitation will still be in place. The LAG settings are for >1Gbps service though LAG is ill suited for such and you'd better off using mgig.
 

They should be able to do link aggregation on WAN, but both of those routers only have 1GB ports on the LAN side. If you want to see speeds greater than 1Gb on your computer, you will need a router that supports 2.5GbE on the LAN ports, so you can connect it to the 2.5GbE Ethernet port on your computer.

But even with only 1Gb LAN ports, you would still be able to benefit from faster overall speeds if multiple devices were being used on the network at the same time (imagine 2Gb internet with two separate devices both using 1Gb at the same time, for example).
 
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The latest Xfinity modem/router combo, the XB7, has a 2.5GbE port and you basically get it for free if you’re paying for unlimited service anyway. Have them send you that one, put it in bridge mode and buy a router with a 2.5GbE WAN port.
 
They should be able to do link aggregation on WAN, but both of those routers only have 1GB ports on the LAN side. If you want to see speeds greater than 1Gb on your computer, you will need a router that supports 2.5GbE on the LAN ports, so you can connect it to the 2.5GbE Ethernet port on your computer.

But even with only 1Gb LAN ports, you would still be able to benefit from faster overall speeds if multiple devices were being used on the network at the same time (imagine 2Gb internet with two separate devices both using 1Gb at the same time, for example).
Having a hard time finding a router that suits my needs here! Can you offer up some suggestions?
 
You do realize there will be no noticeable difference right? 940 is ridiculous as it stands and you will mostly be bottlenecked by other providers when doing downloads, etc.
 
Having a hard time finding a router that suits my needs here! Can you offer up some suggestions?

The Netgear RAX200 can do 2x 1GB with Link Aggregation for WAN, and also has a 2.5GbE port that can be used for your computer.

https://www.netgear.com/home/wifi/routers/rax200/

If it were me I'd just build a pfSense router using a cheap older computer (sandy bridge or better) with dual-port Intel Gigabit adapter for WAN and a 2.5GbE Ethernet adapter for LAN. Plug that into an external 2.5GbE switch. Cost including the 2.5GbE switch would probably be less than some of these more expensive routers like the RAX200.
 
Can't you just run dual NIC on your desktop directly to the modem to test? Much cheaper than getting a new router only to find that it makes no difference.
 
thank you everyone for all your guidance, apparently im completely stupid when it comes to this stuff and have lots of homework to do here. Really appreciate yalls time in helping me though
 
that modem's LAG function is bound to give you more problems than it's worth.

Upgrade to an Arris S33 and start making the migration to 2.5GbE
 
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