Question Receive Buffers and Transmit Buffers and Speedtest.net

Kinnyr90

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Aug 24, 2012
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H,

I have yet another maybe 2 questions.

I have an option as all ethernet controller\cards do Its in the adavced settings of my ethernet card. Its called recieve Buffers and transmit buffers now by default Recieve buffers were set to 8148 and transmit buffers were set to 4096. But where they were 2 different numbers. I thought it might be best to have the transmit buffers also set to 8148. So I went into the registry using the driver key and I manualy changes the transmit buffers to 8148. So now I notice that my throughput getting into websites is a lottle bit snappier if you will. Is this going to decrease my speed for different task that I might do online? Or will it continue to Increase speed further over time?

Or just keep things the same as they are now. Basicly they are not hurting things as far as I can see in terms of speed or anything on my tp-link 10gig Ethernet card connected hard wired cat 7.

Okay so my next question is . When I was just plugged into my 2,5 cable modem and the other end plugged into my 10gig tp-link ethernet card. And I ran a speedtest. From speedtest.net I got 1,440.98 something around there. Now With the ethernet cable going from the back of my modem to the back of my netgear RAX120 Nighthawk. Into the wan internet port because I won't have internet acsess if the ethernet cable going from the modem is plugged anywhere else but the wan port.

On the back of the router. Well now when I run a speedtest. I only get for a speed 940.38 Somewhere around there. And when I go into the ethernet card it shows for a link speed 5.0 Gbps. So is the fact that speedtest.net is giving me lower speed readings. does this mean that when I download from torrent or download anything I won't get the higher speeds that I will get if I was connected just from the modem to the back of the eithernet card? How can I use this router router and still have speedtest.net show me the speeds of 1,440.98 around there give or take. See My ethernet cable is plugged into the multi gig wan port on the back of the router and the other end is plugged into the 10 gig ethernet port on the back of the computer. So the only port that I'm using that is only 1 gig is the wan or internet port on the router. Is there something else I can buy something cheaper than buying another router that will turn the wan port into a multi gig port.

Because I'm thinking it's the fact that the wan internet port on the router only supports a gig, for being the reason that speed test.net has dropped my speed reading to 940.00 Mbps. Give or take. when having just the straight cabke modem connection I got well over a gig with the 1,440.98. Give or take.
 
That is a rather strange router and after reading the manual it seems even a little bit more strange.

So yes your problem is the connection between the router and the modem is only 1gbit.

The recommended method to get the most out of your internet connection without buying another router would be to use the multigig 2.5/5 to connect to the wan port/ modem.

Now this will not do exactly what you want. You machine with the 10gbit port will now only run 1gbit to the router and you will get the same 940mbps rates. The difference is if you have a second machine connected to the router together they can use all the bandwidth but neither machine by itself can use all the bandwidth.

To do this you need a router that has mulitple 2.5/5g ports one you can use for the WAN to the modem and a second you can use to connect your fast pc to.

Maybe for a while run with just the 1gbit and see if you actually feel you need more speed. Many times things on the internet will not even be able to use 1gbit. You could then either buy a new router or reduce your internet from the ISP to 1gbit and save a bit of money. I am going to have to do some thinking when my discount contract comes up for 1gbit, maybe I drop back to 500mbps.
 

Kinnyr90

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So what you are saying is that a switch will not work. Meaning that I couldn't plug an ethernet going from the back of my modem from the 2.5 gig to the multi gig wan or internet port on the back of the switch and then have another cable going from the Multi gig wan port on the back of the router to the back of my computer too the 10 gig ethernet card. I could not have it set up this way. The only way of achieving what I want would be to buy another router that not only has a multi gig port on it but also has a multi gig wan/internet port on it as well correct? Then if I do that. Then I will get the higher speed reading with speedtest.net correct?


Meaning that I will get the 1,442.98. Instead of the 940.89. Give or take. That I get now. Correct.?
And I'm wondering if you could recommend for me a Netgear nighthawk router has not only a multi gig port on it but also has a muti gig WAN port or internet port as it is called.?

Also. You never answered the second part of my question. On the buffer speed but that's okay. I'm more concerned on the speed reading that I get from speedtest.net.
 
I forget without looking those buffers up. If they are the physical buffers that does not mean much. I guess if you have a 10g port and you had it hooked to 1 1gbit network you might buffer data ?. In general if you get any kind of data queuing on ethernet you have a design issue.
The other kind of buffers people talk about is related to the tcp window size. In general you want to let this all run in its defualt auto mode it seems to have little issues. People sometime adjust these if they are transferring on a connection that gets random errors.

You have to remember the only reason you even have a router in most home user cases is to share the single public IP you get from your ISP. This is the NAT function. If there wasn't a need for that function you could use a switch.

I would look at microtik they sell stuff a bit above consumer grade for very low prices compared to commercial grade stuff. No ISP would use it but it is fine for smaller users. You want a device that has routeros support. They sell both routers and switches and they look very similar.
Read the detailed specs on performance. When you start talking very fast equipment the cpu in them can not always run the ports at max speed. You are likely ok since you are not trying to run say 10gbit but they do have equipment that can do stuff that fast.
 

Kinnyr90

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Okay That's fine on the buffers.


so the stuff on microtik does that replace the router? I have been all over netgears website I just spent good money for this netgear RAX 120. I had no idea that that the wan or internet port only supports 1 gig in speed that's the only thing holding me back but I'm not finding any netgear nighthawk routers that have a multi gig wan internet port. So I will look in to the site you gave me Thank you!!
 
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You are correct sometime the fingers type the wrong thing I think :)

After a quick look it appears it may not be as easy as I thought. 2.5g ports and even 10g copper ports seem to be hard to get on commercial equipment. Not real surprised since 2.5 and 5g are mostly sold to home consumers anyway. The device might exist but they are going to be expensive it seems.

So what you may have to do is run what is called router on a stick. You would get a router with at least 1 10g port. You would then plug a switch that supports vlans and also has 10g ports into the port.
The trick is you now define the 10g port going to the switch as a trunk/tagged port. You set 2 different vlans wan and lan on the same port but because of the vlan tags they use a single port. So the 10g port kinda becomes 2 5g ports virtually. On the switch you would would set 1 2.5g port to WAN since that is all your ISP connection will take. You would would set a different 10g port to LAN to hook your pc to. The traffic would now go from the switch up to the router and then back on the same port and go out to the internet router.

Not the most optimal solution but it seems they do not make inexpensive....ie less than 1000s of dollars...routers with multiple 10g ports.

In theory at least your nighthawk might also be able to do this. What I don't know if it supports vlans and the concept of virtual ports/interfaces. It might work on third party firmware but many times you get cpu bottlenecks. To run fast many of these functions are done with hardware and the consumer routers are attempting to do it with software.