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alexir
2005-10-10, 16:27
Hi,

I have a long Ethernet cable going to my living room. If I connect with a laptop, I have to limit the connection speed to 10 Mbps, otherwise the connection won't be established.

When I connect with the SqueezeBox2, it says that it's having problems with the Ethernet connection. How I can setup the SqueezeBox2 to limit the speed to 10 Mbps?

Thanks,
Alex

chrisla
2005-10-10, 16:36
Getting a new cable or switch would likely be your best bet. Ethernet
at 100Mbs is rated at hundreds of meters. Unless you have a _really_
big house, you have a bad cable or switch. Try the cable first, it's
cheap.

Streaming music over a bad connection is always going to be problematic.

-Chris


On 10/10/05, alexir <alexir.1wpmbz (AT) no-mx (DOT) forums.slimdevices.com> wrote:
>
> Hi,
>
> I have a long Ethernet cable going to my living room. If I connect with
> a laptop, I have to limit the connection speed to 10 Mbps, otherwise the
> connection won't be established.
>
> When I connect with the SqueezeBox2, it says that it's having problems
> with the Ethernet connection. How I can setup the SqueezeBox2 to limit
> the speed to 10 Mbps?
>
> Thanks,
> Alex
>
>
> --
> alexir
>

alexir
2005-10-10, 16:45
Getting a new cable or switch would likely be your best bet. Ethernet
at 100Mbs is rated at hundreds of meters. Unless you have a _really_
big house, you have a bad cable or switch. Try the cable first, it's
cheap.

Streaming music over a bad connection is always going to be problematic.

-Chris

Thanks Chris, but the cable is kinda wired through walls, doors etc., so I'd really rather not replace it unless there is no other way. Changing the speed to 10 has always given me a good and reliable connection. I'm still hoping there is a way to do it with SqueezeBox2. If there's no way, I'll look into doing some rewiring.

Michaelwagner
2005-10-10, 16:55
Ethernet at 100Mbs is rated at hundreds of meters.
Only a single 100 meters, if I recall correctly. Or approximately 300 feet. I looked into it once for my factory. That goes all the way from the front office to the back of my factory just fine.

It's actually 100 meters between switches or hubs, but only 2 hubs maximum for any path traversal. So check if you have only hubs in your house and count how many your signal is going through.

The limits are more relaxed for 10baseT, I think 4 or 5 hubs, so if 10 works and 100 doesn't, check how many hubs you're sending your signal through. If it's more than 2, replace the central one with a switch if possible. That's a better solution than putting up with 10baseT (or replacing wire already in the wall).

Is the wire in the wall CAT5? If not, it's not rated for 100BaseT anyways.

Derek Adair
2005-10-10, 16:55
On Mon, 10 Oct 2005, alexir wrote:

> Thanks Chris, but the cable is kinda wired through walls, doors etc.,
> so I'd really rather not replace it unless there is no other way.
> Changing the speed to 10 has always given me a good and reliable
> connection. I'm still hoping there is a way to do it with SqueezeBox2.
> If there's no way, I'll look into doing some rewiring.

Not sure about the Squeezebox's ability there (never seen such a setting),
but if you're loking for anything but rewiring, perhaps a switch that
allows you to set the connection speed is an option? (or an older
switch/hub in the path).

Regards,
Derek Adair
dadair (AT) iglou (DOT) com

pfarrell
2005-10-10, 17:01
On Mon, 2005-10-10 at 16:45 -0700, alexir wrote:
> Thanks Chris, but the cable is kinda wired through walls, doors etc.,
> so I'd really rather not replace it unless there is no other way.
> Changing the speed to 10 has always given me a good and reliable
> connection. I'm still hoping there is a way to do it with SqueezeBox2.
> If there's no way, I'll look into doing some rewiring.

Before you pull zillions of feet of cable thru walls,
I'd run it up the stairs and thru the halls and just
verify that it is a wire problem. It could be a switch
problem. Or you may have hit the cable hanging a picture
or something.


--
Pat Farrell
http://www.pfarrell.com

alexir
2005-10-10, 17:09
Not sure about the Squeezebox's ability there (never seen such a setting),
but if you're loking for anything but rewiring, perhaps a switch that
allows you to set the connection speed is an option? (or an older
switch/hub in the path).

Regards,
Derek Adair
dadair (AT) iglou (DOT) com
Thanks Derek, an old switch for setting this is definitely an option. Still hoping for that hidden setting in the Squeezebox, though :)

alexir
2005-10-10, 17:11
Before you pull zillions of feet of cable thru walls,
I'd run it up the stairs and thru the halls and just
verify that it is a wire problem. It could be a switch
problem. Or you may have hit the cable hanging a picture
or something.


--
Pat Farrell
http://www.pfarrell.com
Pat, I'm quite sure it's a wire problem (not sure which kind of wire it is, but not a very good one, I suspect). Connecting a shorter wire to the same socket with the same equipment works.

-Alex

JJZolx
2005-10-10, 17:12
Is the wire in the wall CAT5? If not, it's not rated for 100BaseT anyways.
That, or it's damaged or badly installed - kinked, crimped, stapled through, or maybe running parallel to electrical wiring or over fixtures.

None of which answers the original question - Can the Squeezebox2's 10/100 ethernet port be fixed at 10mpbs? You could accomplish this by controlling the switch port's speed, but most SOHO switches are unmanaged and have no such control. Over the years I've solved numerous ethernet incompatibilities by fixing a port's speed. Usually, though, it's to fix problems with the auto-speed-negotiation, which sometimes doesn't work as it should.

seanadams
2005-10-10, 17:28
Hi,

I have a long Ethernet cable going to my living room. If I connect with a laptop, I have to limit the connection speed to 10 Mbps, otherwise the connection won't be established.

When I connect with the SqueezeBox2, it says that it's having problems with the Ethernet connection. How I can setup the SqueezeBox2 to limit the speed to 10 Mbps?

Thanks,
Alex

Your cable ends probably aren't installed correctly. It should go:

Orange-white
Orange
Green-white
Blue
Blue-white
Green
Brown-white
Brown

This is important in order to keep the twisted pairs grouped correctly. Ethernet is good for up to 100 meters with correct cabling.

pfarrell
2005-10-10, 17:35
On Mon, 2005-10-10 at 17:11 -0700, alexir wrote:
> Pat, I'm quite sure it's a wire problem (not sure which kind of wire it
> is, but not a very good one, I suspect). Connecting a shorter wire to
> the same socket with the same equipment works.

Just the wire between the wall jack and your SB? or the one
that goes all the way down into the basement? If it is just
the plugin lead, they are cheap and easy to replace.

All ethernet wiring (well at least 99.99%) has four pairs of
wires internal to the cable, and you only need two pairs.
So if only one or two wires are bad, you can just reterminate it
and save dragging wires.


--
Pat
http://www.pfarrell.com/music/slimserver/slimsoftware.html

JJZolx
2005-10-10, 17:37
Your cable ends probably aren't installed correctly. It should go:

Orange-white
Orange
Green-white
Blue
Blue-white
Green
Brown-white
Brown

Well, that's 568B. It could just as easily use 568A, which is:

Green-white
Green
Orange-white
Blue
Blue-white
Orange
Brown-white
Brown

Essentially, the orange and green pairs are swapped in the two different standards. It doesn't really matter which is used, so long as both ends of the connection are the same.

alexir
2005-10-10, 17:49
Green-white
Green
Orange-white
Blue
Blue-white
Orange
Brown-white
Brown

That's why I hate hardware and love software :)
With software, I just go to settings and set the speed to 10. Problem solved. With hardware I have to know what 568B means and how it is different from 568A :)
-Alex

MrC
2005-10-10, 18:09
alexir, you can set the limit on your laptop's NIC to 10mbit and let the sb2 autonegotiate. It will find that your laptop advertises 10mbit, and use that setting.

pfarrell
2005-10-10, 18:12
On Mon, 2005-10-10 at 17:49 -0700, alexir wrote:
> That's why I hate hardware and love software :)
> With software, I just go to settings and set the speed to 10. Problem
> solved. With hardware I have to know what 568B means and how it is
> different from 568A :)

Nah, you just have to be consistent. The signals don't know
what color the wire is. You can invent your own scheme as long
as you do both ends. Might make a difference at way high
speeds, and really long distances, but most of the time
it isn't important.

A is the first letter of the English alphabet, and B is the second.
The great thing about standards is that there are so many to chose from.


--
Pat
http://www.pfarrell.com/music/slimserver/slimsoftware.html

Daryle Tilroe
2005-10-10, 18:16
Pat Farrell wrote:

> All ethernet wiring (well at least 99.99%) has four pairs of
> wires internal to the cable, and you only need two pairs.
> So if only one or two wires are bad, you can just reterminate it
> and save dragging wires.

Don't ignore this suggestion (providing of course you have
checked that both ends are terminated correctly)! If it is
only some fluky damage to one wire; using a different pair
would be an easy fix. You might also want to check the
condition of the spring wires inside the receptacles.
Ensuring they are in the right slots and teasing them
down for a little more tension (or replacing the
receptacle altogether) could be a good idea if it
looks suspect in there. Reseating and/or recrimping
is also another idea, providing there there is enough
wire in there to bite.

P.S. Here is a nice colourful sheet with the two standards:
http://www.lashen.com/vendors/leviton/datacom/TIA568standards.pdf

--
Daryle A. Tilroe

seanadams
2005-10-10, 18:26
On Mon, 2005-10-10 at 17:49 -0700, alexir wrote:
> That's why I hate hardware and love software :)
> With software, I just go to settings and set the speed to 10. Problem
> solved. With hardware I have to know what 568B means and how it is
> different from 568A :)

Nah, you just have to be consistent. The signals don't know
what color the wire is. You can invent your own scheme as long
as you do both ends. Might make a difference at way high
speeds, and really long distances, but most of the time
it isn't important.


The signals don't care what color the wire is, and most devices these days don't even care about polarity, but they definitely care that each signal is twisted with the right partner.

Ethernet depends on differential signalling to reject noise and crosstalk. You need to pair 1&2, 3&6, 4&5, 7&8. If they're not paired right, you can't count on it working even at 10Mbps and even with short cables - I've seen it fail many a time when someone used a RJ45 phone cord (CAT5, but paired differently) in place of an ethernet cord.

(actually 10/100 only uses pairs 1&2 and 3&6)

alexir
2005-10-10, 18:47
alexir, you can set the limit on your laptop's NIC to 10mbit and let the sb2 autonegotiate. It will find that your laptop advertises 10mbit, and use that setting.
Hmm... I'm not sure I understand... Do you mean if the sb2 is connected to the laptop on the other end? My situation is a bit different - I have a cable modem on the other end of that long cable. Or did you mean that I can connect the cable to my laptop, negotiate for 10mbit and the quickly connect sb2?

MrC
2005-10-10, 19:00
Hmm... I'm not sure I understand... Do you mean if the sb2 is connected to the laptop on the other end? My situation is a bit different - I have a cable modem on the other end of that long cable. Or did you mean that I can connect the cable to my laptop, negotiate for 10mbit and the quickly connect sb2?
It is I who misunderstood your plight. I thought you had your laptop running slimserver, and the SB2 connected at the other end of that long cable (creating a peer to peer configuration).

Now I understand that you have trouble connecting with both the SB2 and the laptop.

It would be best to get an up-to-spec, working cable installed that allows your systems to operate as expected.

Sorry for the distraction.

alexir
2005-10-10, 19:04
Now I understand that you have trouble connecting with both the SB2 and the laptop.
No, that's still not the situation :) The connection works fine with the laptop as long as I limit the speed of the connection to 10mbps. My original question was how I can accomplish the same (limiting/specifying the connection speed) with the sb2. I was hoping to find am easy solution (a hidden setting maybe?), one that wouldn't require changing cables, termination, adding hardware etc.

MrC
2005-10-10, 19:11
My definition of "trouble" included your 10mbit workaround.

alexir
2005-10-10, 19:21
My definition of "trouble" included your 10mbit workaround.
Ok, thanks.
So, I guess it's impossible to set the sb2 to 10mbps...
I think I see a WiFi router in my future then :)

Michaelwagner
2005-10-10, 20:18
well, there's one solution to force 10mb.

beg borrow or steal an old 10MB only hub, and stick it in the signal path ...

As for your question, it would need someone who knows details of the hardware to even know if it's possible, like someone from slim, and if so, then someone who knows the details of the firmware to know if there's a hidden option.

seanadams
2005-10-10, 20:29
well, there's one solution to force 10mb.

beg borrow or steal an old 10MB only hub, and stick it in the signal path ...

As for your question, it would need someone who knows details of the hardware to even know if it's possible, like someone from slim, and if so, then someone who knows the details of the firmware to know if there's a hidden option.

There is no hidden option to set it to 10Mbps. Even if there were, I would not recommend this as evidently there is a problem with the cabling. Even if you could get it to link up at 10Mbps you might get spotty performance.

stinkingpig
2005-10-10, 21:19
Michaelwagner wrote:

>chrisla Wrote:
>
>
>>Ethernet at 100Mbs is rated at hundreds of meters.
>>
>>
>Only a single 100 meters, if I recall correctly. Or approximately 300
>feet. I looked into it once for my factory. That goes all the way from
>the front office to the back of my factory just fine.
>
>It's actually 100 meters between switches or hubs, but only 2 hubs
>maximum for any path traversal. So check if you have only hubs in your
>house and count how many your signal is going through.
>
>The limits are more relaxed for 10baseT, I think 4 or 5 hubs, so if 10
>works and 100 doesn't, check how many hubs you're sending your signal
>through. If it's more than 2, replace the central one with a switch if
>possible. That's a better solution than putting up with 10baseT (or
>replacing wire already in the wall).
>
>Is the wire in the wall CAT5? If not, it's not rated for 100BaseT
>anyways.
>
>
>

also that 100 meters assumes no crosstalk or interference from
flourescent light ballasts, microwave ovens, televisions, other cables
carrying electricity, &c... It's maybe not such a real world number.

I'm inclined to distrust cables, I just lost a day last week to finding
out that the reel-up cable in my bag, while perfectly able to pass mail,
web, and IM traffic, was unable to allow tftp through to a router I was
configuring. Replaced the cable, all was fine, reelup cable went in the
round file.

--
Jack At Monkeynoodle Dot Org: It's A Scientific Venture!
"I spent all me tin with the ladies drinking gin
so across the Western ocean I must wander" -- trad.

seanadams
2005-10-10, 22:27
Some anecdotal experience on the 100m rule:

I recently ran a 90m cat6 line. Needed to get from suite 900 in our building to suite 400. However the conduit all goes to suite 100 (they're all in a row), so it had to go there and back again for a total of about 90m.

I had hoped that the link would work at gigabit speed (which is supposed to work over CAT5e at 100m). Come to find after installing it, the switches would only negotiate 100Mbps. After replacing the short cat5e patch cords going from the patch panel to the switch on each end with cat6 patch cords, the link came up at 1000 Mbps.

Just shows how sensitive it gets as speed and distance increase...

seanadams
2005-10-10, 22:31
Also, originally the 100m limit was based on time needed to detect collisions on a shared link for the smallest possible packet. I.e. the time to travel down the wire needs to be short enough that both ends can see every packet in time to detect a collision. I'm not sure if this a constraint any more with switches - I think it's just about signal integrity now.

JJZolx
2005-10-10, 22:48
Also, originally the 100m limit was based on time needed to detect collisions on a shared link for the smallest possible packet. I.e. the time to travel down the wire needs to be short enough that both ends can see every packet in time to detect a collision. I'm not sure if this a constraint any more with switches - I think it's just about signal integrity now.
Any chance of adding port speed control to the SB2 firmware? As I said earlier, I've seen the ability to fix the port speed (and duplex) often solves problems attributable to unreliable auto speed negotiation. Also, as you've experienced, not every cabling run is capable of the higher speed. Maybe the guy has perfectly good, but older Cat3 cabling installed, which is only spec'd to 10 Mbps. If two 10/100 devices are at either end of that connection, it's not hard to imagine them negotiating the higher speed and then failing to be able to reliably sustain it.

alexir
2005-10-11, 00:10
Maybe the guy has perfectly good, but older Cat3 cabling installed, which is only spec'd to 10 Mbps. If two 10/100 devices are at either end of that connection, it's not hard to imagine them negotiating the higher speed and then failing to be able to reliably sustain it.
That sounds like a very good description of my situation. My cable is pretty old (might be Cat3, not sure), but when using a laptop and limiting the connection to 10mbps I get a good and reliable link. With sb2, I complete the ethernet setup process (I'm assuming the negotiated speed is 100), get an IP, then it starts complaining about the ethernet connection. Sounds exactly as your comment about not being able to sustain the negotiated speed. That sb2 firmware upgrade with a speed limit option could just solve the problem for me once and for good...

Michaelwagner
2005-10-11, 06:02
Also, originally the 100m limit was based on time needed to detect collisions on a shared link for the smallest possible packet. I.e. the time to travel down the wire needs to be short enough that both ends can see every packet in time to detect a collision. I'm not sure if this a constraint any more with switches - I think it's just about signal integrity now.
I think that's the reason the fanout rule changed to 2 hubs between switches in 100BaseT. Hubs only regenerate the signal but don't change the "domain" within which collision detection occurs.
Switches define new "collision domains" (I'm making up these terms - I'm sure there are proper ones but I haven't had enough coffee yet to remember them).

Michaelwagner
2005-10-11, 06:06
Any chance of adding port speed control to the SB2 firmware? As I said earlier, I've seen the ability to fix the port speed (and duplex) often solves problems attributable to unreliable auto speed negotiation. Also, as you've experienced, not every cabling run is capable of the higher speed. Maybe the guy has perfectly good, but older Cat3 cabling installed, which is only spec'd to 10 Mbps. If two 10/100 devices are at either end of that connection, it's not hard to imagine them negotiating the higher speed and then failing to be able to reliably sustain it.
Isn't auto speed negotiation based partly on having enough wires, but also partly on sending test packets to see how they fare? To tell you the truth, I never looked into how auto speed negotiation works ... I had the entire factory wired with new cat5 when I moved in (there was no existing ethernet infrastructure) and so it all just works, so I never probed into how it's supposed to back down to 10BaseT, just assumed it did it somehow based on capabilities at both ends of the segment and actual experience. Perhaps the second part of the assumption is wrong.

As to whether it could be added, it depends on the facilities in the ethernet chip (I think Sean posted a link somewhere to the spec sheet) and then if supported at the chip level, someone would have to write the client side "microcode" and a way of setting it up. ...

MrC
2005-10-11, 08:41
Isn't auto speed negotiation based partly on having enough wires, but also partly on sending test packets to see how they fare? To tell you the truth, I never looked into how auto speed negotiation works ... I had the entire factory wired with new cat5 when I moved in (there was no existing ethernet infrastructure) and so it all just works, so I never probed into how it's supposed to back down to 10BaseT, just assumed it did it somehow based on capabilities at both ends of the segment and actual experience. Perhaps the second part of the assumption is wrong.

As to whether it could be added, it depends on the facilities in the ethernet chip (I think Sean posted a link somewhere to the spec sheet) and then if supported at the chip level, someone would have to write the client side "microcode" and a way of setting it up. ...

For 10/100mb, only 4 wires are used.

When link is detected, the two sides send out framing data, and then send out advertisements describing what they can support. They test that they can support the highest capabilities first, and fall back to lower capabilities should test packets fail.

I would have suspected that the SB2 would fall back to 10mb but from the data, it seems that this is not supported or not working correctly.

For my 2c, the consumer world has for the most part moved past 10base-t - time to move forward. Capable hardware is so cheap, it just doesn't make a lot of sense to me to spend time coding, debugging, and testing support for older or problematic configurations.

winstan
2006-11-10, 22:52
Here's another reason why being able to switch a SB3 to 10Mbit would be really nice:
What if I'm using a couple of these http://www.etslan.com/Ethernet.htm and the RG6 run to my living room? These baluns confuse the negotiation process, and they definitely only work at 10M.

I'd very much like to not have to put a 10M switch in series... :(

Michaelwagner
2006-11-11, 08:08
If they only work at 10Mb, then the SB will happily use them.

The SB will use the highest rate it can negotiate.

winstan
2006-11-11, 10:14
Hmn... Seems that negotiation happens based on what the endpoints want, not what the wire can handle. So if one wants 100M and the other 10M, then the 100M node will negotiate down to 10M. If both endpoints want 100M but the line can only handle 10M, then the endpoints have a very hard time figuring that out. In my experience, they don't figure it out... :p

So the only solution I can figure is to be able to force one end or the other down to 10M, which will force the other to follow. Since the SB is already highly programmable, it seems to be the easiest place to add this functionality...

winstan
2006-11-11, 12:15
Well, I found firmware for my router that lets me set port speed...
http://www.dd-wrt.com/