Experts Help Please Settle Arguement - Hub or Switch if ISP offers several IPs

I know this is not a Wireless question but I know the experts here that
I can be trusted for an accurate answer. (One in particular - Hi Jeff)
Conditions:
1) Cable ISP DHCP server offers multiple IPs
2) Common non-routing cable modem.
3) Two computers: different IPs desired for online gaming, browsing etc.
4) No LAN required
5) Using a Router or firewall not part of this discussion

Are these two statements correct?
"As I said, you don't use a switch in this kind of arrangement.
Switches break the network into segments but hubs broadcast to everyone
because it doesn't know where to route packets.
Switches an algorithim for routing packets at Layer 2. If the switch has
determined that packets should go to User A, packets destined for User B
will go to user A first.
When the switch realizes User A was the wrong destination, it will send
out a broadcast across the network at which time User B will respond.
The end result is all the other users get robbed of available bandwidth.

With a hub in place, a broadcast is sent out over the network and a
response is sent back to the hub from the right destination node. The
first segment gets dedicated on a first-come basis."



"If the ISP will allow you to pull 2 or 3 addresses, you need a hub, not
a switch.
The cable modem can't route. If there is a switch in place, packets will
get routed to USER A. When packets come in for USER B, they will
continue to be routed to USER A with a switch in place. In the mean
time, USER B sits and waits. Then the switch realizes USER A is
rejecting the packets so it sends a broadcast across the network. USER B
says, "Hey, I'm over here". Now incoming packets start going to USER B.
When packets come in destined for USER A, they continue to go to USER B,
and so and and so on and so on..."

Thanks for your time!

Jim Beam <(E-Mail Removed)> wrote:
>"As I said, you don't use a switch in this kind of arrangement.
>Switches break the network into segments but hubs broadcast to everyone
>because it doesn't know where to route packets.
[...]
>"If the ISP will allow you to pull 2 or 3 addresses, you need a hub, not
>a switch.
>The cable modem can't route. If there is a switch in place, packets will
>get routed to USER A. When packets come in for USER B, they will
>continue to be routed to USER A with a switch in place. In the mean
>time, USER B sits and waits. Then the switch realizes USER A is
>rejecting the packets so it sends a broadcast across the network. USER B
>says, "Hey, I'm over here". Now incoming packets start going to USER B.
>When packets come in destined for USER A, they continue to go to USER B,
>and so and and so on and so on..."

The person who said that has no idea what they are talking about. I
don't even know where to start. Maybe it's just late, but IMHO, you
can't educate them or straighten them out, just shake your head and
walk away.

Jim Beam <(E-Mail Removed)> wrote in
news:(E-Mail Removed):

> Subject: Experts Help Please Settle Arguement - Hub or Switch if ISP
> offers several IPs From: Jim Beam <(E-Mail Removed)>
> Newsgroups: alt.internet.wireless
>
> I know this is not a Wireless question but I know the experts here
> that I can be trusted for an accurate answer. (One in particular - Hi
> Jeff) Conditions:
> 1) Cable ISP DHCP server offers multiple IPs
> 2) Common non-routing cable modem.
> 3) Two computers: different IPs desired for online gaming, browsing
> etc. 4) No LAN required
> 5) Using a Router or firewall not part of this discussion
>
> Are these two statements correct?
> "As I said, you don't use a switch in this kind of arrangement.
> Switches break the network into segments but hubs broadcast to
> everyone because it doesn't know where to route packets.
> Switches an algorithim for routing packets at Layer 2. If the switch
> has determined that packets should go to User A, packets destined for
> User B will go to user A first.
> When the switch realizes User A was the wrong destination, it will
> send out a broadcast across the network at which time User B will
> respond. The end result is all the other users get robbed of available
> bandwidth.
>
> With a hub in place, a broadcast is sent out over the network and a
> response is sent back to the hub from the right destination node. The
> first segment gets dedicated on a first-come basis."

You need to understand the basics.

http://www.homenethelp.com/web/expla...d-switches.asp

>
>
>
> "If the ISP will allow you to pull 2 or 3 addresses, you need a hub,
> not a switch.

You need a FW appliance or NAT router that can work with more than one IP
from the ISP. I guess there are some modems that can do it too like
Motorola that can work with more than one IP from the ISP.

> The cable modem can't route. If there is a switch in place, packets
> will get routed to USER A. When packets come in for USER B, they will
> continue to be routed to USER A with a switch in place. In the mean
> time, USER B sits and waits. Then the switch realizes USER A is
> rejecting the packets so it sends a broadcast across the network. USER
> B says, "Hey, I'm over here". Now incoming packets start going to USER
> B. When packets come in destined for USER A, they continue to go to
> USER B, and so and and so on and so on..."

A hub will broadcast to all ports because it doesn't know what machine on
what port wants the inbound traffic. Therefore, you have traffic
collision when a machine on a port using a hub sends outbound while
inbound traffic that doesn't belong to it comes down the port, which
slows the traffic on a hub down. A swicth eliminates this problem as it
knows from what port inbound traffic belongs to based on the NIC's MAC
and (port number I think) it applies in the traffic along with the other
features a smart switch has that a dumb hub doesn't have.

A hub or switch doesn't route traffic by IP to a machine a router or FW
appliance does that.

Routers have built in switch technology and a router can be configured to
be just a switch and plugged into a router that is a gateway router as an
example.

Duane

>
> The person who said that has no idea what they are talking about. I
> don't even know where to start. Maybe it's just late, but IMHO, you
> can't educate them or straighten them out, just shake your head and
> walk away.

You have to help a little bit now. <g>

Duane

On Sat, 03 Dec 2005 21:39:36 GMT, Jim Beam <(E-Mail Removed)> wrote:

>I know this is not a Wireless question but I know the experts here that
>I can be trusted for an accurate answer. (One in particular - Hi Jeff)
>Conditions:
>1) Cable ISP DHCP server offers multiple IPs

They do? Which ISP? I couldn't find any consumer cable ISP service
that offered multiple IP's on the left coast. I couldn't even find
one that offered a static IP. What county? What planet?

>2) Common non-routing cable modem.

Name withheld to confuse the answers? If you've ever read any of my
answers, you'll note that withholding the hardware and OS desription
is a capital crime.

>3) Two computers: different IPs desired for online gaming, browsing etc.

I'll assume Windoze XP Home on both. Most users don't want to admit
that they're using a Microsoft product and tend to

>4) No LAN required

What does that mean? Whether you're using wireless or wires, it's
still a LAN.

>5) Using a Router or firewall not part of this discussion

Why not?

>Are these two statements correct?

That assumes I understand what they are trying to say. It would have
been much easier if you simply disclose what you're trying to
accomplish and what you have to work with. Answering that question is
MUCH easier than decoding whatever the following means.

>"As I said, you don't use a switch in this kind of arrangement.
>Switches break the network into segments but hubs broadcast to everyone
>because it doesn't know where to route packets.
>Switches an algorithim for routing packets at Layer 2. If the switch has
>determined that packets should go to User A, packets destined for User B
>will go to user A first.
>When the switch realizes User A was the wrong destination, it will send
>out a broadcast across the network at which time User B will respond.
>The end result is all the other users get robbed of available bandwidth.
>
>With a hub in place, a broadcast is sent out over the network and a
>response is sent back to the hub from the right destination node. The
>first segment gets dedicated on a first-come basis."

What a bunch of unintelligible gibberish. There's also some drivel
that appear wrong. For example, there is no "robbing" of bandwidth by
either a switch or a hub. The traffic is distributed equally between
the two destinations depending upon packet size and internal FIFO
buffering.

>"If the ISP will allow you to pull 2 or 3 addresses, you need a hub, not
>a switch.

Wrong. A switch will work just fine. I have several DSL installation
that use SBC's overpriced 5 static IP address service. I even
scribbled a document on how to use it properly with the goofy routeing
system that SBC uses to deliver the 5 IP's.
http://www.LearnByDestroying.com/crud/5IP.txt
Note that I show an 8 port hub in the top drawing instead of a switch.
That's because I have a monitoring PC shoved into the hub to sniff the
traffic and generate traffic statistics. I usually use a managed
switch (with SNMP) for the purpose, but I wanted to simplify the
setup. At this time, the box is a Netgear FS108 ethernet switch (not
hub) because I got bored with looking at the graphs.

>The cable modem can't route. If there is a switch in place, packets will
>get routed to USER A. When packets come in for USER B, they will
>continue to be routed to USER A with a switch in place. In the mean
>time, USER B sits and waits. Then the switch realizes USER A is
>rejecting the packets so it sends a broadcast across the network. USER B
>says, "Hey, I'm over here". Now incoming packets start going to USER B.
>When packets come in destined for USER A, they continue to go to USER B,
>and so and and so on and so on..."

All wrong. Totally and completely wrong. Absolutely, miserably,
horribly, wrong. Wrong, wrong, wrong, wrong, wrong, wrong....etc.

Think of an ethernet switch as an ethernet bridge with more than 2
ports. For a simple bridge, they way it works is for the bridge to
build a table of:
MAC address <----> port numbers
Each ethernet port has a shopping list of destination MAC addresses
that are seen on that port. If a MAC address moves from one port to
another (by moving the connecting cable), the MAC to port table will
instanly update to the new configuration.

Traffic that has a destination MAC address across the bridge will get
passed across the bridge. Traffic, where the destination address is
NOT across the bridge, will not go through the bridge. Broadcasts
have no destination address, therefore they get passed across the
bridge.

Now, we add more ports to the bridge and call it an ethernet switch.
Everything is exactly the same except there are more ports. Traffic
with a destination address of one specific port goes only to that
port. Traffic with no destination address (i.e. broadcasts) go to all
ports.

Since there's no router, your ISP will the MAC address of the
destination computah in its ARP table.
MAC address <-----> IP Address
All the packets destined for a specific machine will go directly to
that machine via the switched port.

At this point, I can get really techy about the different types of
switches (crossbar and store-n-forward), per port buffering, 10/100
speed transitions, internal bus bandwidth, NWAY negotiation, flow
control, and how it all affects performance distribution and latency.
I'll keep it simple and only off that there's no obvious effect until
you try to get wire speed performance. For what you're doing, it
probably matters little if you're using a hub or a switch as long as
the hub/switch speed is faster than your internet connection.

While I'm on the subject, there's one really nice thing about
switches. A switch will do full duplex while a hub will not. There
may not be much performance benifit for internet traffic, but it sure
speeds things up for LAN traffic.

If you non-cleverly select a "dual speed 10/100 hub" instead of a
switch, be prepared for some rather disgusting performance issues due
to 10/100 speed transition, internal buffering, and no flow control,
issues.

>Thanks for your time!

So, where did you dig up that gibberish? Never mind. I don't wanna
know.

--
Jeff Liebermann (E-Mail Removed)
150 Felker St #D http://www.LearnByDestroying.com
Santa Cruz CA 95060 http://802.11junk.com
Skype: JeffLiebermann AE6KS 831-336-2558

[POSTED TO alt.internet.wireless - REPLY ON USENET PLEASE]

In <(E-Mail Removed)> on Sat, 03 Dec 2005 21:39:36
GMT, Jim Beam <(E-Mail Removed)> wrote:

>I know this is not a Wireless question but I know the experts here that
>I can be trusted for an accurate answer. ...

Not a good reason to be posting here.

--
Best regards, FAQ FOR CINGULAR WIRELESS
John Navas <http://en.wikibooks.org/wiki/Cingular_Wireless_FAQ>

> They do? Which ISP? I couldn't find any consumer cable ISP service
> that offered multiple IP's on the left coast. I couldn't even find
> one that offered a static IP. What county? What planet?

FWIW, NTL (UK) consumer cable co, offers multiple IP's.

On Sun, 04 Dec 2005 08:57:23 GMT, David Taylor <(E-Mail Removed)>
wrote:

>> They do? Which ISP? I couldn't find any consumer cable ISP service
>> that offered multiple IP's on the left coast. I couldn't even find
>> one that offered a static IP. What county? What planet?

>FWIW, NTL (UK) consumer cable co, offers multiple IP's.

Sigh. I need a brain transplant.

When I wrote "multiple IP's", I automagically assumed static IP
addresses which is a problem I'm currently dealing with for a
customer. Of course almost, all cable broadband providers offer more
than one dynamic IP address. That's the way they originally wanted
everyone to connect so they could charge customers by the computah.

That's two screwups for me in one day. Time to do something else for
a while.

.... which reminds me. I could use some content help with the FAQ.
http://en.wikibooks.org/wiki/FAQ_for...ernet.wireless
http://en.wikibooks.org/wiki/FAQ_for...wireless/Wi-Fi
In particular, the Troubleshooting section could use someonething on
Windoze related issues such as WSC versus manufacturer supplied
drivers. I'll add the spelling errors later.

--
Jeff Liebermann (E-Mail Removed)
150 Felker St #D http://www.LearnByDestroying.com
Santa Cruz CA 95060 http://802.11junk.com
Skype: JeffLiebermann AE6KS 831-336-2558

Jim Beam <(E-Mail Removed)> wrote:

>I know this is not a Wireless question but I know the experts here that
>I can be trusted for an accurate answer. (One in particular - Hi Jeff)
>Conditions:
>1) Cable ISP DHCP server offers multiple IPs
>2) Common non-routing cable modem.
>3) Two computers: different IPs desired for online gaming, browsing etc.
>4) No LAN required
(anytime you use an ethernet cable there is a LAN, sometimes even
when you usb cable too)
>5) Using a Router or firewall not part of this discussion

There is a lot of lack of understanding in this post on both sides.

Hubs and switches will both work perfectly in this scenario. Both
support basic ethernet which is all you need.

The major difference : Switches increase performance and security over
a hub.


Hubs are electronic repeaters. What electricity comes in on port gets
repeated out all others. That simple. Everyone hears everything.
Increased opportunity for collisions to occur requiring clients to
retransmit lost packets.


Switches send the minimal amount of traffic to each port.
- Every port hears broadcast
- Every port hears multicasts (advanced switching and routing
technology can reduce this further)
- Traffic sent to a single device(unicast mac address) will be sent to
one port only.
- The exception is if the switch is trying to send to a device and it
hasn't seen any traffic from the unicast mac address in 5
minutes(default timing, but can vary). If it doesn't know what port it
lives on it sends the traffic to all other ports (unicast flooding)

That's the majority of it.

IPs don't matter because basic switch/hub technology works at layer
2/Mac Address which doesn't involve IP addresses. Layer 3/IP relies on
Layer2 to work. Advanced switching technology can get into IP
features, but we're not talking about anything so advanced as that
here.




>Are these two statements correct?
>"As I said, you don't use a switch in this kind of arrangement.
>Switches break the network into segments but hubs broadcast to everyone
>because it doesn't know where to route packets.
>Switches an algorithim for routing packets at Layer 2. If the switch has
>determined that packets should go to User A, packets destined for User B
>will go to user A first.
>When the switch realizes User A was the wrong destination, it will send
>out a broadcast across the network at which time User B will respond.
>The end result is all the other users get robbed of available bandwidth.

Nope.

>With a hub in place, a broadcast is sent out over the network and a
>response is sent back to the hub from the right destination node. The
>first segment gets dedicated on a first-come basis."

There is no "segmentation" in hubs.



>"If the ISP will allow you to pull 2 or 3 addresses, you need a hub, not
>a switch.

Either works. Switches are always better. Hubs are so 1995.

>The cable modem can't route. If there is a switch in place, packets will
>get routed to USER A. When packets come in for USER B, they will
>continue to be routed to USER A with a switch in place. In the mean
>time, USER B sits and waits. Then the switch realizes USER A is
>rejecting the packets so it sends a broadcast across the network. USER B
>says, "Hey, I'm over here". Now incoming packets start going to USER B.
>When packets come in destined for USER A, they continue to go to USER B,
>and so and and so on and so on..."

Nope none of that happens.

>Thanks for your time!

DiGiTAL_ViNYL (no email)

In article <(E-Mail Removed)>, (E-Mail Removed)
says...
THANKS all for the explanations!