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

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.

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

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

Why not?

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.

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.

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.

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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.

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.

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

Reply to
Jeff Liebermann
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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.

Reply to
William P.N. Smith

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!

Reply to
Jim Beam

Jim Beam wrote in news: snipped-for-privacy@news.easynews.com:

You need to understand the basics.

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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.

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 :)

Reply to
Duane Arnold

You have to help a little bit now.

Duane :)

Reply to
Duane Arnold

Not a good reason to be posting here.

Reply to
John Navas

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

Reply to
David Taylor

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.

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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.

Reply to
Jeff Liebermann

(anytime you use an ethernet cable there is a LAN, sometimes even when you usb cable too)

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.

Nope.

There is no "segmentation" in hubs.

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

Nope none of that happens.

DiGiTAL_ViNYL (no email)

Reply to
DigitalVinyl

In article , snipped-for-privacy@jb.beam says... THANKS all for the explanations!

Reply to
Jim Beam

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