Really dumb wireless questions

[Ken90630]

An expert on wireless I'm not, so forgive me:

When surfing the Web via a wireless connection to the router (as opposed to a direct connection via an ethernet cable), is the download speed typically lower? In other words, let's say a person is paying for 15 Mbps from a broadband cable provider (Comcast, Time Warner, Cox or whoever), and they get that speed when direct-connected. Should they also get that speed when connected wirelessly, or does it typically drop some? And if so, how much of a drop is typical?

For discussion purposes, I'm mainly concerned with download speed here (upload, not so much).

 

[drebo]

You will generally see lower connection speeds over wireless, depending on the speed of your Internet connection.

For instance, with Wireless-G, the absolute max speed you can connect at is 54 megabits. Half duplex and overhead drop the "real life" maximum connection speed to about 24 megabits. Interference and distance will lower that further. Antenna quality of the wireless adapter in the computer and on the wireless AP/router will lower that further.

If you've got a 15 megabit connection to the Internet, it is quite possible it will be slower when browsed over wireless as opposed to wired. If, on the other hand, you had a 6 megabit Internet connection, you might never notice a difference. If you had a 20 megabit Internet connection, you would almost certainly notice a stark difference between wireless and wired.

 

[ImDonly1]

Go to speedtest.net and check your speeds on wired and wireless.

 

[AstroGuardian]

Drebo you are not entirely right.

If you pay for 15mbps to the ISP and your connection to the wireless device is greater than 15mbps and ping is lower than 10ms than you will not feel any difference...
This claim is many times tested and approved...

 

[bad_monkey]

I have a 15 Mbps connection (20 with speedboost...man, I hate TimeWarner) and I frequently get 20+ Mbps when I go to speedtest.net or TW's own test site even when connected via wireless. That is not to say that what others have said isn't true, just my own personal experience.

 

[degibson]

Drebo you are not entirely right.

If you pay for 15mbps to the ISP and your connection to the wireless device is greater than 15mbps and ping is lower than 10ms than you will not feel any difference...
This claim is many times tested and approved...

(emphasis added)

Remember there's usually a difference between the advertised speed and the one you'll get, even with a solid, wired connection. Make sure you run speed test both wired and unwired.

That said, you might end up seeing slower browsing speeds, even with a 'fast' wireless 'connection'. There are a couple of reasons for this.

1. There's no such thing as a wireless 'connection'. It's wireless. It's not connected! Windows tells you it's connected because colloquially that means you have the ability to exchange packets. But in reality, packets are flung every which way in 3-space... some get to where they want to be, some don't. In other words, packet loss rate is higher in wireless communication, and that can play havoc with things like HTTP.

2. Think of the path between you and the internet as a series of tubes. Each tube has a width, that's its bandwidth. The smallest tube between you and the internet determines your connection speed. For most people, the smallest tube is the one between their house and the ISP. But sometimes, the smallest one is crossing a USB 1.0 if you have an old wireless device, so try to keep an open mind.

 

[spidey07]

Drebo you are not entirely right.

If you pay for 15mbps to the ISP and your connection to the wireless device is greater than 15mbps and ping is lower than 10ms than you will not feel any difference...
This claim is many times tested and approved...

That is not correct. Wireless has interference and is generally much slower in overall thruput than 15 Mbs. Not to mention the added latency of the constant retransmissions.

Of course it all depends on ones environment.

 

[airdata]

Drebo you are not entirely right.

If you pay for 15mbps to the ISP and your connection to the wireless device is greater than 15mbps and ping is lower than 10ms than you will not feel any difference...
This claim is many times tested and approved...

The pimple-faced sales person at Frys one time was trying to get me to get a 100mbps wireless router and insisted if I got the other that I would have slower speeds despite my 5mbps/2mbps internet connect.

Wireless is however prone to packet drops. When i used wireless several years ago from a room toward the back of the house, downloaded files would frequently be currupt because of lost packets.

 

[AstroGuardian]

(emphasis added)

Remember there's usually a difference between the advertised speed and the one you'll get, even with a solid, wired connection. Make sure you run speed test both wired and unwired.

That said, you might end up seeing slower browsing speeds, even with a 'fast' wireless 'connection'. There are a couple of reasons for this.

1. There's no such thing as a wireless 'connection'. It's wireless. It's not connected! Windows tells you it's connected because colloquially that means you have the ability to exchange packets. But in reality, packets are flung every which way in 3-space... some get to where they want to be, some don't. In other words, packet loss rate is higher in wireless communication, and that can play havoc with things like HTTP.

2. Think of the path between you and the internet as a series of tubes. Each tube has a width, that's its bandwidth. The smallest tube between you and the internet determines your connection speed. For most people, the smallest tube is the one between their house and the ISP. But sometimes, the smallest one is crossing a USB 1.0 if you have an old wireless device, so try to keep an open mind.

Under 2 you are right. That's what i said.

Under 1... What? Are you serious? Packets flung in 3-space? Jesus Christ mate! Signals transmitted by the antenna in 3 dimensions. Your receiver antenna picks up those signals and transfers it locally to packets. So there is no such thing as "some get to where they want to be, some don't". If the antenna catches the signals needed to form a packet , that's ok. If not it just retries or the packet is lost... If you lose many packets your connection speed drops. And yes, there is a wireless connection. The word "connection" comes assuming all needed packets needed are transmitted and received. Just like with wired connections. Wired or wireless it's the same thing no matter whether it's copper, optic or wireless...

 

[AstroGuardian]

Wireless is however prone to packet drops. When i used wireless several years ago from a room toward the back of the house, downloaded files would frequently be currupt because of lost packets.

That was probably caused by bad hard drive or partition problem.
That has NEVER happened to me or anyone i know before. If too many packets are lost, you will lose the connection and the file transfer will be disrupted. Or it can take ages to transfer a single file. There is NO WAY packet loss can cause data corruption. NO WAY!

 

[Destiny]

The fastest speed I ever got from Timewarner was 30Mbps from wireless router when I tested on speedtest.net ... but then again they were upgrading their networks and the other half of their customers were without service at that time...

 

[degibson]

Under 2 you are right. That's what i said.

Under 1... What? Are you serious? Packets flung in 3-space? Jesus Christ mate! Signals transmitted by the antenna in 3 dimensions. Your receiver antenna picks up those signals and transfers it locally to packets. So there is no such thing as "some get to where they want to be, some don't". If the antenna catches the signals needed to form a packet , that's ok. If not it just retries or the packet is lost... If you lose many packets your connection speed drops. And yes, there is a wireless connection. The word "connection" comes assuming all needed packets needed are transmitted and received. Just like with wired connections. Wired or wireless it's the same thing no matter whether it's copper, optic or wireless...

Whoa, there Avatar fan! Relax, I was making a colloquialism. The thread is titled "Really dumb wireless questions". I figured I would explain what is going on at the hand-wave level.

If you prefer the non-hand-wave level: 802.x is a layer-2 service. It provides a link between endpoints to a layer 3 service, usually IP. Most wireless is omnidirectional and subject to substantial signal integrity loss from background interference. And all wireless loses signal strength in inverse proportion to the square of the distance between sender and observer. This makes it even more prone than other level 2 services to packet loss and packet corruption.

Couple these effects with a bona-fide level 4 (e.g., TCP-reno) connection and you get all kinds of interference effects and bandwidth sawtoothing.

 

[RadiclDreamer]

The pimple-faced sales person at Frys one time was trying to get me to get a 100mbps wireless router and insisted if I got the other that I would have slower speeds despite my 5mbps/2mbps internet connect.

Wireless is however prone to packet drops. When i used wireless several years ago from a room toward the back of the house, downloaded files would frequently be currupt because of lost packets.

They should not be corrupt because of lost packets, the protocol should take care of that.

 

[spidey07]

In summary. Wireless is slow.

 

[AstroGuardian]

Whoa, there Avatar fan! Relax, I was making a colloquialism. The thread is titled "Really dumb wireless questions". I figured I would explain what is going on at the hand-wave level.

Oh right... sorry... missed the "Really dumb wireless questions"
My bad... but we explained the point... right?

 

[degibson]

Oh right... sorry... missed the "Really dumb wireless questions"
My bad... but we explained the point... right?

Oh I think we beat it to death!

They should not be corrupt because of lost packets, the protocol should take care of that.

The whole point is that TCP's retransmission is optimized for the common case of few lossy packets. Rolling back an entire window for a single lost packet is pretty lame when losses are frequent. Sure TCP will guarantee correct, in-order delivery... but not fast delivery.

 

[FoxFifth]

An expert on wireless I'm not, so forgive me:

When surfing the Web via a wireless connection to the router (as opposed to a direct connection via an ethernet cable), is the download speed typically lower? In other words, let's say a person is paying for 15 Mbps from a broadband cable provider (Comcast, Time Warner, Cox or whoever), and they get that speed when direct-connected. Should they also get that speed when connected wirelessly, or does it typically drop some? And if so, how much of a drop is typical?

For discussion purposes, I'm mainly concerned with download speed here (upload, not so much).

I'm currently using a Motorola 6120 modem and a Linksys WRT54GL wireless router and get 20 to 24 Mbps downloading with Comcast's Performance (12 with Powerboost to 15) and I can't detect a measurable difference between using it wirelessly and using it with an ethernet connection -- i.e., I may be paying a small penalty for using wireless but when I test both ways on speedtest.net, the variation is up and down by very small amounts and no more variation than I see from one test to the next when testing just one type of connection. I may have a near ideal situation as their are only 4 or 5 other wireless networks visible in my neighborhood, I'm in a single story house, etc. On the other hand I previously had a Motorola SBG900 modem/wireless router combined and on that there was roughly a 40% penalty downloading (and hardly any penalty uploading). I talked to two levels of Motorola customer support and they said the 40% loss I experienced was "normal."

 

[her209]

The OP is assuming he'll be getting max throughput from his residential ISP which is unrealistic.

:awe:

 

[Ken90630]

Thanks, All.

Some of the high-tech terminology went over my head, but I think I understand the issue better now. In short, wireless speed will typically be lower than wired (on the same network) unless an ideal sitch exists in which there's no wireless interference, the PC is very close to the wireless router, there's very little other wireless traffic in the neighborhood, and the router (& its antenna) are of high quality. Is that a good, general rule of thumb?

 

[spidey07]

Thanks, All.

Some of the high-tech terminology went over my head, but I think I understand the issue better now. In short, wireless speed will typically be lower than wired (on the same network) unless an ideal sitch exists in which there's no wireless interference, the PC is very close to the wireless router, there's very little other wireless traffic in the neighborhood, and the router (& its antenna) are of high quality. Is that a good, general rule of thumb?

Pretty close. But wireless will always be much slower than wired even in a perfect environment.

 

[Narmer]

Wrong thread.