okay here is the deal, i have Comcast Extreme 50 ( Now Extreme 100 with the new package roll out today ) im still running a 10/100 network throughout the house. for some reason i can only hit about 80-82 Mbps no matter what i do, or what browser i use.
the big question......
if i upgrade/update my entire network to a gigabit platform will i get my rated speeds of 100 Mbps?
LAN Speeds
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Re: LAN Speeds
Plug in something with a gigabit port directly to the modem (bypass the router even) and speed test it that way, that will tell you if the LAN is holding you back or not. My guess is it probably is having an impact because usually ISPs over-provision the customer lines so they will actually hit the advertised speeds on speed test sites (barring congestion).
Re: LAN Speeds
x2 -- assuming the modem has a GBit port, hook up a computer to it directly to get the real speeds.
Besides that, the numbers aren't that far off. W/o gaps betw. frames, TCP/IP over Fast Ethernet (100BASE-TX, MTU 1500) caps at 11,865,420 B/s (94,923,360 b/s, 90.5 Mb/s) payload.
BTW, in the US DOCSIS 3.0 specs payloads of 38 Mb/s down and 27 Mb/s up per channel and the hardware must at least support 4 channels in each direction (up to the provider how many are actually used.) If your numbers fit into multiples of these you are not throttled.
Besides that, the numbers aren't that far off. W/o gaps betw. frames, TCP/IP over Fast Ethernet (100BASE-TX, MTU 1500) caps at 11,865,420 B/s (94,923,360 b/s, 90.5 Mb/s) payload.
BTW, in the US DOCSIS 3.0 specs payloads of 38 Mb/s down and 27 Mb/s up per channel and the hardware must at least support 4 channels in each direction (up to the provider how many are actually used.) If your numbers fit into multiples of these you are not throttled.
Re: LAN Speeds
Forgot -- no need to re-wire the whole house. Just use a GB switch to connect the modem and limit the computers to 100Mb/s if your wiring isn't cat5e. That will help when multiple computers access the modem at once. If you have a server, make sure it is connected to the switch at 1Gb/s for the same reason.
Re: LAN Speeds
If your network is 10/100 you will never see 100mb/s and 80-90 is typical - to see that full 100mb/s you'll need to upgrade your equipment to gigabit.
Docsis 3 modems have Gigabit Ethernet ports on them. You're always going to lose a little speed through any consumer router, and particularly on wireless, this is due to network overhead. The wireless protocols add more overhead because of the way they work, and then you have the NAT in the router that also adds some overhead. And performance will vary from brand to brand and model to model, as well. Also, your speed test could be meaningless if that server resides outside your providers network. Odds are, they have a speed test server inside their network that you should use. If you use a server out on the internet somewhere, then you are subjecting that test to conditions that are beyond your ISP's control, once it leaves their network. Also, you shouldn't do speedtests during peak usage hours, that just hogs bandwidth that should be available for everyone to be actually using. (10am to midnight, are the hours I see the most usage)
Above all, remember, that no matter what you're getting, cable modems are shared-bandwidth, not dedicated. If you were dedicated, you'd be paying 2 grand a month for that kind of speed. There is a reason there is an "up-to" clause in your acceptable use policy.
Also, in Docsis 3 modems, when doing a speed test, even right off the modem, don't be surpised if you don't see the 95-100mb/s speed untill the 2nd or 3rd test, because the CMTS/modem will adjust the service flows depending on the current usage, and when you try to pull a lot of traffic through it, it'll adjust the channel loading dynamically and bump up.
Docsis 3 spec states 42mb/s per channel(raw), with the protocol overhead, you typically see 38.6mb/s per channel, which irons out to 304mb/s or so per 8 channels. If you have a speedtest server sitting right next to the CMTS, and there is nobody else using that card, hooked right into the modem, wide open, you could see about 297mb/s off that modem (this is what I saw in my lab testing).
Upstream is a bird of a different color. The most you can get currently is 30mb/s channel (raw) because the upstream is at max.. 64qam (downstream is 256qam) that is roughly 26mb/s useable upstream per channel. Now, most providers are not bonding more than 2 upstreams, if they are bonding them at all. This is due to the inevitable amount of noise below the 20mhz frequency in most systems, plus other possible return carriers they may have running for boxes and voice ports, etc.. when your typical top frequency is 42mhz (meaning the edge of the channel must stop *before* 42mhz) that leaves you very little room for extra channels.
Now, Those on FTTH (or fiber-deep hfc) may have more bonded upstreams due to the cleaner return that is inherent to that kind of plant. You can easily run all 4 upstream channels in that kind of setup.
Now, a few years from now, when Docsis 3.1 equipment finally starts filtering into the market, you may start to see significant changes to that, as there is talk about moving the return split up higher in frequency and also moving to 4096qam OFDM channels that go above 1ghz - for theoretical 10gb/s down and 2-5gb/s up capacity.
Docsis 3 modems have Gigabit Ethernet ports on them. You're always going to lose a little speed through any consumer router, and particularly on wireless, this is due to network overhead. The wireless protocols add more overhead because of the way they work, and then you have the NAT in the router that also adds some overhead. And performance will vary from brand to brand and model to model, as well. Also, your speed test could be meaningless if that server resides outside your providers network. Odds are, they have a speed test server inside their network that you should use. If you use a server out on the internet somewhere, then you are subjecting that test to conditions that are beyond your ISP's control, once it leaves their network. Also, you shouldn't do speedtests during peak usage hours, that just hogs bandwidth that should be available for everyone to be actually using. (10am to midnight, are the hours I see the most usage)
Above all, remember, that no matter what you're getting, cable modems are shared-bandwidth, not dedicated. If you were dedicated, you'd be paying 2 grand a month for that kind of speed. There is a reason there is an "up-to" clause in your acceptable use policy.
Also, in Docsis 3 modems, when doing a speed test, even right off the modem, don't be surpised if you don't see the 95-100mb/s speed untill the 2nd or 3rd test, because the CMTS/modem will adjust the service flows depending on the current usage, and when you try to pull a lot of traffic through it, it'll adjust the channel loading dynamically and bump up.
Docsis 3 spec states 42mb/s per channel(raw), with the protocol overhead, you typically see 38.6mb/s per channel, which irons out to 304mb/s or so per 8 channels. If you have a speedtest server sitting right next to the CMTS, and there is nobody else using that card, hooked right into the modem, wide open, you could see about 297mb/s off that modem (this is what I saw in my lab testing).
Upstream is a bird of a different color. The most you can get currently is 30mb/s channel (raw) because the upstream is at max.. 64qam (downstream is 256qam) that is roughly 26mb/s useable upstream per channel. Now, most providers are not bonding more than 2 upstreams, if they are bonding them at all. This is due to the inevitable amount of noise below the 20mhz frequency in most systems, plus other possible return carriers they may have running for boxes and voice ports, etc.. when your typical top frequency is 42mhz (meaning the edge of the channel must stop *before* 42mhz) that leaves you very little room for extra channels.
Now, Those on FTTH (or fiber-deep hfc) may have more bonded upstreams due to the cleaner return that is inherent to that kind of plant. You can easily run all 4 upstream channels in that kind of setup.
Now, a few years from now, when Docsis 3.1 equipment finally starts filtering into the market, you may start to see significant changes to that, as there is talk about moving the return split up higher in frequency and also moving to 4096qam OFDM channels that go above 1ghz - for theoretical 10gb/s down and 2-5gb/s up capacity.
Re: LAN Speeds
the modem uses all 4 up channels right now, giving us about 20Mb Up. but even with the gigabit network if all we can see is about 80-90 then i guess no need for upgrading. we'll just have to sit at the max of the 100 Mb network. ill toy with the idea for a bit.
sorry i THOUGHT it was all 4 channels.. its only 2
sorry i THOUGHT it was all 4 channels.. its only 2