alt.certification.network-plus

Author

Bridge vs Switch

Bay

2003-08-24, 2:27 pm

Hi, the functionality between Bridge and Switch are so smiliar. I still get
these two devices confused all the time. What is the difference between
these two devices? Both devices seem can do the job to keep network traffic
from interferring with the rest of the network. What do you think?

Andy Barkl

2003-08-24, 3:28 pm

"Bay" <Bay@worldpeace.com> wrote in message
news:zL62b.246515$uu5.50559@sccrnsc04...
> Hi, the functionality between Bridge and Switch are so smiliar. I still
get
> these two devices confused all the time. What is the difference between
> these two devices? Both devices seem can do the job to keep network
traffic
> from interferring with the rest of the network. What do you think?

The only real difference is the number of ports!

Gareth

2003-08-24, 7:28 pm

"Andy Barkl" <abarkl@NOSPAMhotmail.com> wrote in message
news:Rn72b.22852$nf3.5161@fed1read07...
> "Bay" <Bay@worldpeace.com> wrote in message
> news:zL62b.246515$uu5.50559@sccrnsc04...
> > Hi, the functionality between Bridge and Switch are so smiliar. I still
> get
> > these two devices confused all the time. What is the difference between
> > these two devices? Both devices seem can do the job to keep network
> traffic
> > from interferring with the rest of the network. What do you think?
>
> The only real difference is the number of ports!
>
>

Andy,

Had the very same discussion with some people in a networking forum a while
back.

Although I take your point that bridges and switches perform exactly the
same function at a basic level, bridges tend to be used to link differing
networks together - for instance, a wireless bridge would "transparently"
connect a wired Ethernet network to a wireless (possibly 802.11b) network.

What you say is correct, but I tend to think that allowing for the above
explanation gives a wider picture of practicality and use.

HTH,

G.

C Voyer

2003-08-25, 9:26 am

Gareth

2003-08-25, 2:25 pm

"C Voyer" <cvoyer@wtvl.net> wrote in message
news:vkk1j9pnamhb3f@corp.supernews.com...
> Well first of all, a switch has more ports than a hub I believe. Also, a
> switch can be classified as a kind of hub while a bridge cannot. I also
> believe a switch is more intelligent than a hub.
> Correct me if I am wrong.
>

Yes, I would agree that a switch belongs in the hub family more than it does
the bridge family. Three types of hub:

Passive hub - broadcasts data to all connected ports.
Active hub - the norm, broadcasts to all connected ports, and regenerates
(repeats) the signal.
Switching hub - intelligent hub, only broadcasts data to the port associated
with the target MAC address.

I think that to close the issue, one might say that a switching hub is an
active hub, that employs bridging technology between ports.

G.

C Voyer

2003-08-26, 8:25 am

"Gareth" <gaz@gaz.org> wrote in message
news:3f4a4fb5$0$46007$65c69314
@mercury.nildram.net...
>
> "C Voyer" <cvoyer@wtvl.net> wrote in message
> news:vkk1j9pnamhb3f@corp.supernews.com...
> > Well first of all, a switch has more ports than a hub I believe. Also, a
> > switch can be classified as a kind of hub while a bridge cannot. I also
> > believe a switch is more intelligent than a hub.
> > Correct me if I am wrong.
> >
>
> Yes, I would agree that a switch belongs in the hub family more than it
does
> the bridge family. Three types of hub:
>
> Passive hub - broadcasts data to all connected ports.
> Active hub - the norm, broadcasts to all connected ports, and regenerates
> (repeats) the signal.
> Switching hub - intelligent hub, only broadcasts data to the port
associated
> with the target MAC address.
>
> I think that to close the issue, one might say that a switching hub is an
> active hub, that employs bridging technology between ports.
>
> G.
>
>

"A switching hub routes data directly from one node to another while a hub
sends data through all nodes."

Gareth

2003-08-26, 12:36 pm

"C Voyer" <cvoyer@wtvl.net> wrote in message
news:vkmhvp3anf7ibc@corp.supernews.com...
>
> "Gareth" <gaz@gaz.org> wrote in message
> news:3f4a4fb5$0$46007$65c69314
@mercury.nildram.net...
> >
> > "C Voyer" <cvoyer@wtvl.net> wrote in message
> > news:vkk1j9pnamhb3f@corp.supernews.com...
> > > Well first of all, a switch has more ports than a hub I believe. Also,
a[col
or=darkred]
> > > switch can be classified as a kind of hub while a bridge cannot. I[/color]
also[
color=darkred]
> > > believe a switch is more intelligent than a hub.
> > > Correct me if I am wrong.
> > >
> >
> > Yes, I would agree that a switch belongs in the hub family more than it
> does
> > the bridge family. Three types of hub:
> >
> > Passive hub - broadcasts data to all connected ports.
> > Active hub - the norm, broadcasts to all connected ports, and[/color]
regenerates
> > (repeats) the signal.
> > Switching hub - intelligent hub, only broadcasts data to the port
> associated
> > with the target MAC address.
> >
> > I think that to close the issue, one might say that a switching hub is
an
> > active hub, that employs bridging technology between ports.
> >
> > G.
> >
> >
>
> "A switching hub routes data directly from one node to another while a hub
> sends data through all nodes."

Isn't that what I said? :-)

G.

C Voyer

2003-08-26, 1:34 pm

"Gareth" <gaz@gaz.org> wrote in message
news:3f4b877f$0$46003$65c69314
@mercury.nildram.net...
>
> "C Voyer" <cvoyer@wtvl.net> wrote in message
> news:vkmhvp3anf7ibc@corp.supernews.com...
> >
> > "Gareth" <gaz@gaz.org> wrote in message
> > news:3f4a4fb5$0$46007$65c69314
@mercury.nildram.net...
> > >
> > > "C Voyer" <cvoyer@wtvl.net> wrote in message
> > > news:vkk1j9pnamhb3f@corp.supernews.com...
> > > > Well first of all, a switch has more ports than a hub I believe.
Also,
> a
> > > > switch can be classified as a kind of hub while a bridge cannot. I
> also
> > > > believe a switch is more intelligent than a hub.
> > > > Correct me if I am wrong.
> > > >
> > >
> > > Yes, I would agree that a switch belongs in the hub family more than
it
> > does
> > > the bridge family. Three types of hub:
> > >
> > > Passive hub - broadcasts data to all connected ports.
> > > Active hub - the norm, broadcasts to all connected ports, and
> regenerates[color
=darkred]
> > > (repeats) the signal.
> > > Switching hub - intelligent hub, only broadcasts data to the port
> > associated
> > > with the target MAC address.
> > >
> > > I think that to close the issue, one might say that a switching hub is
> an

> > > active hub, that employs bridging technology between ports.
> > >
> > > G.
> > >
> > >
> >
> > "A switching hub routes data directly from one node to another while a[/color]
hub
> > sends data through all nodes."
>
> Isn't that what I said? :-)
>
> G.
>
>

Yes I was trying to put in words that might be used on an actual test

André Franke

2003-08-26, 5:29 pm

You are all wrong.
A repeater is an amplifier, amplifying signal as well as noise.
A hub is nothing but a distribution facility. A physical bus topology
resides inside a hub.
An active hub is a multiport repeater (a distrib. facil. with repeater
functionality).
A bridge forwards traffic to the physical destination segment,
separating collision domains but merging broadcast domains, making its
forwarding decisions based on physical addresses (MAC) controlled by
software.
A switch is a special kind of a multiport bridge where the bridging
functionality is controlled by hardware. VLANS segment the switch an
connected segments into different broadcast domains based on logical
grouping of hosts or segments. The term layer 3 switch refers to
VLANS.
A router forwards traffic to the destination logical segment, making
its forwarding decisions based on logical addresses (IP,IPX),
separating collision domains as well as broadcast domains. Different
VLANS can only be connected by a router since they are broadcast
domains.

regards
André

C Voyer

2003-08-26, 7:25 pm

"André Franke" <dump.it@digital-filestore.de> wrote in message
news:gninkvkq7uddgl15ep7q5ek5f
qhenom72t@4ax.com...
> You are all wrong.
> A repeater is an amplifier, amplifying signal as well as noise.
> A hub is nothing but a distribution facility. A physical bus topology
> resides inside a hub.
> An active hub is a multiport repeater (a distrib. facil. with repeater
> functionality).
> A bridge forwards traffic to the physical destination segment,
> separating collision domains but merging broadcast domains, making its
> forwarding decisions based on physical addresses (MAC) controlled by
> software.
> A switch is a special kind of a multiport bridge where the bridging
> functionality is controlled by hardware. VLANS segment the switch an
> connected segments into different broadcast domains based on logical
> grouping of hosts or segments. The term layer 3 switch refers to
> VLANS.
> A router forwards traffic to the destination logical segment, making
> its forwarding decisions based on logical addresses (IP,IPX),
> separating collision domains as well as broadcast domains. Different
> VLANS can only be connected by a router since they are broadcast
> domains.
>
> regards
> André

Most texts refer to a switch as being a type of hub and there is actually a
question on several practice tests that says.....

Which of the following is NOT a type of hub.
A) Repeaters
B) Hub
C) Switch
D) Bridge

I am pretty sure it was A and D

André Franke

2003-08-26, 7:25 pm

"C Voyer" <cvoyer@wtvl.net> wrote:

>Most texts refer to a switch as being a type of hub and there is actually a
>question on several practice tests that says.....
>
>Which of the following is NOT a type of hub.
>A) Repeaters
>B) Hub
>C) Switch
>D) Bridge
>
>I am pretty sure it was A and D

Well, now you see:
That's the difference between CCNA and N+
The CCNA learns this stuff at the first three days, since it is very,
very basic. The N+ learns to think like those vendors selling some
telephone cable as a crossover and a switch as a hub or vice versa.
That's even the source of the term "layer 3 switch", which only refers
to frame tagging for VLANs.
If a switch was a hub, how could it be that a hub splits bandwidth to
all ports while a switch dedicates the full bandwidth to each port?
For your test question three answers would really apply since only a
hub is a type of hub. If it was "Which of the following is NOT a type
of repeater?" the C and D would apply because a (modern active) hub is
a repeater on every port.

regards
André

Gareth

2003-08-27, 9:25 am

"André Franke" <dump.it@digital-filestore.de> wrote in message
news:m9pnkv4rf2rb71a0ruakn8nj3
fc7vjtv3a@4ax.com...
> "C Voyer" <cvoyer@wtvl.net> wrote:
>
> >Most texts refer to a switch as being a type of hub and there is actually
a
> >question on several practice tests that says.....
> >
> >Which of the following is NOT a type of hub.
> >A) Repeaters
> >B) Hub
> >C) Switch
> >D) Bridge
> >
> >I am pretty sure it was A and D
>
> Well, now you see:
> That's the difference between CCNA and N+
> The CCNA learns this stuff at the first three days, since it is very,
> very basic. The N+ learns to think like those vendors selling some
> telephone cable as a crossover and a switch as a hub or vice versa.
> That's even the source of the term "layer 3 switch", which only refers
> to frame tagging for VLANs.
> If a switch was a hub, how could it be that a hub splits bandwidth to
> all ports while a switch dedicates the full bandwidth to each port?
> For your test question three answers would really apply since only a
> hub is a type of hub. If it was "Which of the following is NOT a type
> of repeater?" the C and D would apply because a (modern active) hub is
> a repeater on every port.
>
> regards
> André

André,

To be honest, I think you are being pulled into the same trap as identified
right at the start. Voyer, you would be right with A and D. If you lookup
the definition of hub, by definition it is merely a meeting place of
multiple points.

Andre, you might want to consider re-reading what has already been said, and
at first glance it seems that you've just told us all we're wrong, and then
just repeated what we said.

G.

André Franke

2003-08-27, 10:25 am

"Gareth" <gaz@gaz.org> wrote:

>To be honest, I think you are being pulled into the same trap as identified
>right at the start. Voyer, you would be right with A and D. If you lookup
>the definition of hub, by definition it is merely a meeting place of
>multiple points.
>
>Andre, you might want to consider re-reading what has already been said, and
>at first glance it seems that you've just told us all we're wrong, and then
>just repeated what we said.

I don't think so, Gareth.

Here is what has been stated so far:

||Well first of all, a switch has more ports than a hub I believe.

Correct? No!
There are 32 port hubs out there and 4 port switches too

||Also, a switch can be classified as a kind of hub while a bridge cannot.

Correct? No!
Since a switch is a multiport bridge you can't say one of the is some
kind of hub while the other is not. Also a hub works in a very
different way than a switch or bridge. Hubs work at the physical layer
while switch and bridge work at the datalink layer of the OSI
reference model.

||I also believe a switch is more intelligent than a hub.

Correct? Yes!
Since a hub is only a bit more than a cable, while the switch has to
decide where to forward the traffic and where not.

||Yes, I would agree that a switch belongs in the hub family more than
||it does the bridge family.

Correct? No!
A 16 port switch is a row of ports where a (hardware-) bridge is
established between two of the ports when the need arises from the
switches forwarding decision.

||Three types of hub:

I'd put only two of the following into the hub family.

||Passive hub - broadcasts data to all connected ports.

Right!

||Active hub - the norm, broadcasts to all connected ports, and
||regenerates (repeats) the signal.

Right!
That's why the name multiport repeater applies to modern hubs.

||Switching hub - intelligent hub, only broadcasts data to the port
||>associated with the target MAC address.

Wrong!
If it forwards traffic based on MAC addresses it is per definition a
bridge and if it has more than two ports and works hardware controlled
it is a multiport bridge which is called a switch.
The term "switching hub" was invented by soemone who didn't know
better. I'm not sure, but I think I remember they called the first
switches that way, because the term "switch" was not present at that
time. Later on they simply called switches as switches since there are
switches inside them

Forget about the "switching hub". Today it is either a hub or a switch
but never it is both.

||"A switching hub routes data directly from one node to another while a
||hub sends data through all nodes."

A very good joke, which I would like to ask your permission to quote
it as "Some Words of Wisdom".

A hub that switches is no hub but a switch.
A switch that routes is no switch but a router.
Everything below the network layer is just forwarding, while routing
is the functionality to decide what path to take where the path may
have one or more relaying stations. You may say now, that you can
connect a switch to another switch and yet another switch, but no
routing would take place here, only the MAC address of the destination
host is known to the switch port and not the path.
I don't know what terminology is used by the N+ exam, but I know if
you don't keep your terms clear, you will badly fail in that
buisiness.
Be sure that you never confuse the devices. Categorize them easily by
the OSI layers at which they work:
physical: repeater, hub
datalink: bridge, switch
network : router (VLANs of a switch)

regards
André

Gareth

2003-08-27, 4:25 pm

"André Franke" <dump.it@digital-filestore.de> wrote in message
news:1v9pkv87qigs229ggmu8fqhrj
7sam16mht@4ax.com...
> "Gareth" <gaz@gaz.org> wrote:
>
> >To be honest, I think you are being pulled into the same trap as
identified
> >right at the start. Voyer, you would be right with A and D. If you
lookup
> >the definition of hub, by definition it is merely a meeting place of
> >multiple points.
> >
> >Andre, you might want to consider re-reading what has already been said,
and
> >at first glance it seems that you've just told us all we're wrong, and
then
> >just repeated what we said.
>
> I don't think so, Gareth.
>
> Here is what has been stated so far:
>
> ||Well first of all, a switch has more ports than a hub I believe.
>
> Correct? No!
> There are 32 port hubs out there and 4 port switches too
>
> ||Also, a switch can be classified as a kind of hub while a bridge cannot.
>
> Correct? No!
> Since a switch is a multiport bridge you can't say one of the is some
> kind of hub while the other is not. Also a hub works in a very
> different way than a switch or bridge. Hubs work at the physical layer
> while switch and bridge work at the datalink layer of the OSI
> reference model.
>
> ||I also believe a switch is more intelligent than a hub.
>
> Correct? Yes!
> Since a hub is only a bit more than a cable, while the switch has to
> decide where to forward the traffic and where not.
>
> ||Yes, I would agree that a switch belongs in the hub family more than
> ||it does the bridge family.
>
> Correct? No!
> A 16 port switch is a row of ports where a (hardware-) bridge is
> established between two of the ports when the need arises from the
> switches forwarding decision.
>
> ||Three types of hub:
>
> I'd put only two of the following into the hub family.
>
> ||Passive hub - broadcasts data to all connected ports.
>
> Right!
>
> ||Active hub - the norm, broadcasts to all connected ports, and
> ||regenerates (repeats) the signal.
>
> Right!
> That's why the name multiport repeater applies to modern hubs.
>
> ||Switching hub - intelligent hub, only broadcasts data to the port
> ||>associated with the target MAC address.
>
> Wrong!
> If it forwards traffic based on MAC addresses it is per definition a
> bridge and if it has more than two ports and works hardware controlled
> it is a multiport bridge which is called a switch.
> The term "switching hub" was invented by soemone who didn't know
> better. I'm not sure, but I think I remember they called the first
> switches that way, because the term "switch" was not present at that
> time. Later on they simply called switches as switches since there are
> switches inside them

> Forget about the "switching hub". Today it is either a hub or a switch
> but never it is both.
>
> ||"A switching hub routes data directly from one node to another while a
> ||hub sends data through all nodes."
>
> A very good joke, which I would like to ask your permission to quote
> it as "Some Words of Wisdom".
>
> A hub that switches is no hub but a switch.
> A switch that routes is no switch but a router.
> Everything below the network layer is just forwarding, while routing
> is the functionality to decide what path to take where the path may
> have one or more relaying stations. You may say now, that you can
> connect a switch to another switch and yet another switch, but no
> routing would take place here, only the MAC address of the destination
> host is known to the switch port and not the path.
> I don't know what terminology is used by the N+ exam, but I know if
> you don't keep your terms clear, you will badly fail in that
> buisiness.
> Be sure that you never confuse the devices. Categorize them easily by
> the OSI layers at which they work:
> physical: repeater, hub
> datalink: bridge, switch
> network : router (VLANs of a switch)
>
> regards
> André

André,

With the exception of one or two statements that other people have
incorrectly said, and a good statement in your past paragraph, you're
splitting hairs. It's for this reason that I'm going to stop monitoring this
thread, so please don't be offended if you don't receive anymore replies
based in this thread.

G.

Chopper

2003-08-27, 4:25 pm

<snip>

> André,
>
> With the exception of one or two statements that other people have
> incorrectly said, and a good statement in your past paragraph, you're
> splitting hairs. It's for this reason that I'm going to stop monitoring
this
> thread, so please don't be offended if you don't receive anymore replies
> based in this thread.
>
> G.
>

I think Andre (sorry, can't find the acute e) was spot on.
Splitting hairs? Well if that's what it takes...

C Voyer

2003-08-27, 6:25 pm

"André Franke" <dump.it@digital-filestore.de> wrote in message
news:1v9pkv87qigs229ggmu8fqhrj
7sam16mht@4ax.com...
> "Gareth" <gaz@gaz.org> wrote:
>
> >To be honest, I think you are being pulled into the same trap as
identified
> >right at the start. Voyer, you would be right with A and D. If you
lookup
> >the definition of hub, by definition it is merely a meeting place of
> >multiple points.
> >
> >Andre, you might want to consider re-reading what has already been said,
and
> >at first glance it seems that you've just told us all we're wrong, and
then
> >just repeated what we said.
>
> I don't think so, Gareth.
>
> Here is what has been stated so far:
>
> ||Well first of all, a switch has more ports than a hub I believe.
>
> Correct? No!
> There are 32 port hubs out there and 4 port switches too

Here I was mistaken but it was in my wording. I meant to say that a switch
has more ports than a bridge. I am sorry I accidentaly said hub.

> ||Also, a switch can be classified as a kind of hub while a bridge cannot.
>
> Correct? No!
> Since a switch is a multiport bridge you can't say one of the is some
> kind of hub while the other is not. Also a hub works in a very
> different way than a switch or bridge. Hubs work at the physical layer
> while switch and bridge work at the datalink layer of the OSI
> reference model.

A switch as far as I know is in the hub family while a bridge is not because
it is only used to bridge to LANs together.

> ||I also believe a switch is more intelligent than a hub.
>
> Correct? Yes!
> Since a hub is only a bit more than a cable, while the switch has to
> decide where to forward the traffic and where not.
>
> ||Yes, I would agree that a switch belongs in the hub family more than
> ||it does the bridge family.
>
> Correct? No!
> A 16 port switch is a row of ports where a (hardware-) bridge is
> established between two of the ports when the need arises from the
> switches forwarding decision.
>
> ||Three types of hub:
>
> I'd put only two of the following into the hub family.
>
> ||Passive hub - broadcasts data to all connected ports.
>
> Right!
>
> ||Active hub - the norm, broadcasts to all connected ports, and
> ||regenerates (repeats) the signal.
>
> Right!
> That's why the name multiport repeater applies to modern hubs.
>
> ||Switching hub - intelligent hub, only broadcasts data to the port
> ||>associated with the target MAC address.
>
> Wrong!
> If it forwards traffic based on MAC addresses it is per definition a
> bridge and if it has more than two ports and works hardware controlled
> it is a multiport bridge which is called a switch.
> The term "switching hub" was invented by soemone who didn't know
> better. I'm not sure, but I think I remember they called the first
> switches that way, because the term "switch" was not present at that
> time. Later on they simply called switches as switches since there are
> switches inside them

André Franke

2003-08-28, 2:25 pm

"Gareth" <gaz@gaz.org> wrote:
>
>With the exception of one or two statements that other people have
>incorrectly said, and a good statement in your past paragraph, you're
>splitting hairs. It's for this reason that I'm going to stop monitoring this
>thread, so please don't be offended if you don't receive anymore replies
>based in this thread.

It wasn't my intention to split hairs or to offend anyone.
I only wanted to point out, that with your understanding of hubs,
bridges and switches I would have had no chance to pass my CCNA,
because you have to distinguish these devices accurately. Your whole
network could stand or fall with the selection of the right devices.
If anyone is offended by what I wrote, I seriously apologize.
I only wanted to clear up the obvious confusion.

As for the "joke" statement: I simply couldn't resist. Sorry for that
one too.

regards
André

FireSword

2003-08-31, 8:30 pm

Here is one difference, Bridges use software to maintain tables, switches
work at hardware level.
Also, Bridges use only one type of switching, Store-And-forward. That means
that the bridge needs to receive the complete frame and check it for errors
before sending it on another port.
Switches can use store-and-forward or cut-trough and fast-forward.
in cut-trough switching, one port needs to receive only the first 64K of the
frame, enough to check for a collision error, before forwarding the frame.
Fast-Forward is the fastest method, it only have to check the destination of
the frame before forwarding, this mode does not do any type of error
checking.

"Bay" <Bay@worldpeace.com> wrote in message
news:zL62b.246515$uu5.50559@sccrnsc04...
> Hi, the functionality between Bridge and Switch are so smiliar. I still
get
> these two devices confused all the time. What is the difference between
> these two devices? Both devices seem can do the job to keep network
traffic
> from interferring with the rest of the network. What do you think?
>
>

FireSword

2003-08-31, 10:29 pm

Iwill have to disagree on the VLANS statement.
VLAN operation is istill a layer 2 function, it depends on tags added to the
layer2 portion of the frame, that's why you still need a layer3
device(router) to communicate between VLANS.

A layer 3 switch is one who incorporates routing functions and therefore
does not need a router to pass traffic between VLANS.

"André Franke" <dump.it@digital-filestore.de> wrote in message
news:gninkvkq7uddgl15ep7q5ek5f
qhenom72t@4ax.com...
> You are all wrong.
> A repeater is an amplifier, amplifying signal as well as noise.
> A hub is nothing but a distribution facility. A physical bus topology
> resides inside a hub.
> An active hub is a multiport repeater (a distrib. facil. with repeater
> functionality).
> A bridge forwards traffic to the physical destination segment,
> separating collision domains but merging broadcast domains, making its
> forwarding decisions based on physical addresses (MAC) controlled by
> software.
> A switch is a special kind of a multiport bridge where the bridging
> functionality is controlled by hardware. VLANS segment the switch an
> connected segments into different broadcast domains based on logical
> grouping of hosts or segments. The term layer 3 switch refers to
> VLANS.
> A router forwards traffic to the destination logical segment, making
> its forwarding decisions based on logical addresses (IP,IPX),
> separating collision domains as well as broadcast domains. Different
> VLANS can only be connected by a router since they are broadcast
> domains.
>
> regards
> André

FireSword

2003-08-31, 10:29 pm

"C Voyer" <cvoyer@wtvl.net> wrote in message
news:vkno3png9f5u77@corp.supernews.com...
>
> "André Franke" <dump.it@digital-filestore.de> wrote in message
> news:gninkvkq7uddgl15ep7q5ek5f
qhenom72t@4ax.com...
> > You are all wrong.
> > A repeater is an amplifier, amplifying signal as well as noise.
> > A hub is nothing but a distribution facility. A physical bus topology
> > resides inside a hub.
> > An active hub is a multiport repeater (a distrib. facil. with repeater
> > functionality).
> > A bridge forwards traffic to the physical destination segment,
> > separating collision domains but merging broadcast domains, making its
> > forwarding decisions based on physical addresses (MAC) controlled by
> > software.
> > A switch is a special kind of a multiport bridge where the bridging
> > functionality is controlled by hardware. VLANS segment the switch an
> > connected segments into different broadcast domains based on logical
> > grouping of hosts or segments. The term layer 3 switch refers to
> > VLANS.
> > A router forwards traffic to the destination logical segment, making
> > its forwarding decisions based on logical addresses (IP,IPX),
> > separating collision domains as well as broadcast domains. Different
> > VLANS can only be connected by a router since they are broadcast
> > domains.
> >
> > regards
> > André
>
> Most texts refer to a switch as being a type of hub and there is actually
a
> question on several practice tests that says.....
>
> Which of the following is NOT a type of hub.
> A) Repeaters
> B) Hub
> C) Switch
> D) Bridge
>
> I am pretty sure it was A and D
>
>
>

FireSword

2003-08-31, 10:29 pm

A switch and a hub are VERY, VERY different.

"C Voyer" <cvoyer@wtvl.net> wrote in message
news:vkno3png9f5u77@corp.supernews.com...
>
> "André Franke" <dump.it@digital-filestore.de> wrote in message
> news:gninkvkq7uddgl15ep7q5ek5f
qhenom72t@4ax.com...
> > You are all wrong.
> > A repeater is an amplifier, amplifying signal as well as noise.
> > A hub is nothing but a distribution facility. A physical bus topology
> > resides inside a hub.
> > An active hub is a multiport repeater (a distrib. facil. with repeater
> > functionality).
> > A bridge forwards traffic to the physical destination segment,
> > separating collision domains but merging broadcast domains, making its
> > forwarding decisions based on physical addresses (MAC) controlled by
> > software.
> > A switch is a special kind of a multiport bridge where the bridging
> > functionality is controlled by hardware. VLANS segment the switch an
> > connected segments into different broadcast domains based on logical
> > grouping of hosts or segments. The term layer 3 switch refers to
> > VLANS.
> > A router forwards traffic to the destination logical segment, making
> > its forwarding decisions based on logical addresses (IP,IPX),
> > separating collision domains as well as broadcast domains. Different
> > VLANS can only be connected by a router since they are broadcast
> > domains.
> >
> > regards
> > André
>
> Most texts refer to a switch as being a type of hub and there is actually
a
> question on several practice tests that says.....
>
> Which of the following is NOT a type of hub.
> A) Repeaters
> B) Hub
> C) Switch
> D) Bridge
>
> I am pretty sure it was A and D
>
>
>

FireSword

2003-08-31, 10:29 pm

yeah... C and D are correct..

"Gareth" <gaz@gaz.org> wrote in message
news:3f4ca625$0$45999$65c69314
@mercury.nildram.net...
>
> "André Franke" <dump.it@digital-filestore.de> wrote in message
> news:m9pnkv4rf2rb71a0ruakn8nj3
fc7vjtv3a@4ax.com...
> > "C Voyer" <cvoyer@wtvl.net> wrote:
> >
> > >Most texts refer to a switch as being a type of hub and there is
actually
> a
> > >question on several practice tests that says.....
> > >
> > >Which of the following is NOT a type of hub.
> > >A) Repeaters
> > >B) Hub
> > >C) Switch
> > >D) Bridge
> > >
> > >I am pretty sure it was A and D
> >
> > Well, now you see:
> > That's the difference between CCNA and N+
> > The CCNA learns this stuff at the first three days, since it is very,
> > very basic. The N+ learns to think like those vendors selling some
> > telephone cable as a crossover and a switch as a hub or vice versa.
> > That's even the source of the term "layer 3 switch", which only refers
> > to frame tagging for VLANs.
> > If a switch was a hub, how could it be that a hub splits bandwidth to
> > all ports while a switch dedicates the full bandwidth to each port?
> > For your test question three answers would really apply since only a
> > hub is a type of hub. If it was "Which of the following is NOT a type
> > of repeater?" the C and D would apply because a (modern active) hub is
> > a repeater on every port.
> >
> > regards
> > André
>
> André,
>
> To be honest, I think you are being pulled into the same trap as
identified
> right at the start. Voyer, you would be right with A and D. If you lookup
> the definition of hub, by definition it is merely a meeting place of
> multiple points.
>
> Andre, you might want to consider re-reading what has already been said,
and
> at first glance it seems that you've just told us all we're wrong, and
then
> just repeated what we said.
>
> G.
>
>
>

André Franke

2003-09-01, 12:27 am

"FireSword" <joxel-spamguard-@hotmail.com> wrote:

>Iwill have to disagree on the VLANS statement.
>VLAN operation is istill a layer 2 function, it depends on tags added to the
>layer2 portion of the frame, that's why you still need a layer3
>device(router) to communicate between VLANS.

As for ISL the tags are added to the IP packets, which makes routing
between VLANs possible.
Cisco states:
|The ISL protocol is a packet-tagging protocol that contains a standard
|Ethernet frame and the VLAN information associated with that frame.
at the page:
http://www.cisco.com/univercd/cc/td...prt7/xcvlan.htm

>A layer 3 switch is one who incorporates routing functions and therefore
>does not need a router to pass traffic between VLANS.

This is also the reason why a switch capable of ISL is called a layer3
switch, since it "routes" the traffic to the appropriate VLAN based on
the layer3 tag.

regards
André

FireSword

2003-09-01, 8:25 pm

VLAN Tags are not added to ip packets, tagging is protocol independent
because it only modifies the layer 2 portion of the frame, and only while it
is being switched.

"André Franke" <dump.it@digital-filestore.de> wrote in message
news:egf5lvskn2tjo7654pc6lq82l
b0n1j72m8@4ax.com...
> "FireSword" <joxel-spamguard-@hotmail.com> wrote:
>
> >Iwill have to disagree on the VLANS statement.
> >VLAN operation is istill a layer 2 function, it depends on tags added to
the
> >layer2 portion of the frame, that's why you still need a layer3
> >device(router) to communicate between VLANS.
>
> As for ISL the tags are added to the IP packets, which makes routing
> between VLANs possible.
> Cisco states:
> |The ISL protocol is a packet-tagging protocol that contains a standard
> |Ethernet frame and the VLAN information associated with that frame.
> at the page:
>
http://www.cisco.com/univercd/cc/td...prt7/xcvlan.htm
>
> >A layer 3 switch is one who incorporates routing functions and therefore
> >does not need a router to pass traffic between VLANS.
>
> This is also the reason why a switch capable of ISL is called a layer3
> switch, since it "routes" the traffic to the appropriate VLAN based on
> the layer3 tag.
>
> regards
> André

JimW±

2003-09-07, 2:29 pm

If you see that Q on the real test, demand your money back

Andr=E9 Franke <dump.it@digital-filestore.de> wrote:
> "C Voyer" <cvoyer@wtvl.net> wrote:
>=20
>> Most texts refer to a switch as being a type of hub and there is
>> actually a question on several practice tests that says.....
>>=20
>> Which of the following is NOT a type of hub.
>> A) Repeaters
>> B) Hub
>> C) Switch
>> D) Bridge
>>=20
>> I am pretty sure it was A and D
>=20
> Well, now you see:
> That's the difference between CCNA and N+
> The CCNA learns this stuff at the first three days, since it is very,
> very basic. The N+ learns to think like those vendors selling some
> telephone cable as a crossover and a switch as a hub or vice versa.
> That's even the source of the term "layer 3 switch", which only refers
> to frame tagging for VLANs.
> If a switch was a hub, how could it be that a hub splits bandwidth to
> all ports while a switch dedicates the full bandwidth to each port?
> For your test question three answers would really apply since only a
> hub is a type of hub. If it was "Which of the following is NOT a type
> of repeater?" the C and D would apply because a (modern active) hub is
> a repeater on every port.
>=20
> regards
> Andr=E9

Sponsored Links