differences between a Switch and a Router ?

Discussion in 'Computer Support' started by fros, Dec 25, 2003.

  1. fros

    fros Guest

    * I would like to know the functional differences between a Switch and a
    Router ?

    I know that a Hub is different from a Switch.
    A Hub connects all the machines together, but doesn't process "which machine
    is speaking first" in the same organised way that a switch can.This
    apparently can lead to "congesttion" on the network.

    I have setup a home LAN - 3 machines to a 4 port router & the router to a
    high speed modem - so I have an idea of
    what the router does.

    Then, I saw a professional IT person setup a small LAN with 2 machinesnow,
    but with more to be added in the future, but he first cabled the 2 machines
    into a 4 port hub, and then the hub into a 4 port router, & the router to a
    modem.

    * I'd like to understand why it would be done this way.

    When I asked, he rambled on in terms I could not understand (not to mention
    the accent which I couldn't interpret either).
     
    fros, Dec 25, 2003
    #1
    1. Advertisements

  2. fros

    Mara Guest

    Mara, Dec 25, 2003
    #2
    1. Advertisements

  3. fros

    Richard Guest

    A switch means you have total control over which device is connected.
    A hub, without power, merely connects all devices on it to the machine and
    does not supply power to the devices.
    A hub with power, allows low voltage items to be powered through the hub.
    A router is a more intelligent, sophisticated hub.
    A router has a minicomputer system built into it where a hub does not.

    You might check out www.techtv.com for some info on hubs and routers.
     
    Richard, Dec 25, 2003
    #3
  4. fros

    fros Guest

    thanks!
    great link (and to related links....)
     
    fros, Dec 25, 2003
    #4
  5. fros

    Mara Guest

    You're welcome.
     
    Mara, Dec 25, 2003
    #5
  6. fros

    why? Guest

    That would be an intelligent managed switch rather than a dumb switch.
    What has power to do with it?

    If you are going to mention PoE devices , usually more midrange to
    expensive switches at least use the correct name - Power-over-Ethernet.

    Then there is the option, power the hub electrical supply over the
    unused wire pairs or the power devices connected to the hub types ,
    Inline PoE and so on.
    Wrong, hubs don't connect different LANs/WANs together, they connect
    segments together generally with no processing ability so can't be
    compared to a router.
    The problem is with the term hub - (a collection of connections) it can
    be used to describe - repeater (intelligent / passive) and a switch.

    A switch has a controller as well. Again that term hub can refer to
    several things.
    (Unless you mean dual speed hubs that have a bridge (decision making)
    between the 2 speed domains) or even a simple bridge that makes
    decisions based on system addresses.
    Another stunning Richard post.

    Was the OPs example of why 2 PCs to hub to router to hard to answer?

    Me
     
    why?, Dec 25, 2003
    #6
  7. fros

    Richard Guest

    why? wrote:

    That would be an intelligent managed switch rather than a dumb switch.
    voltage items to be powered through the hub.[/QUOTE]

    He wanted to know the basic differences.
    A switch does nothing more than connect a device to the system. One at a
    time.
    You could have a zillion position switch and only of those devices will be
    connected.
    Like watching tv. You turn the switch and you watch only one "channel".

    You have a router which is a bit smarter. Instead of being told what to
    connect and when, it decides what to connect and when and to where.
    Simlar to a radio scanner constantly listening for traffic.

    Basic hubs have no power capabilities. These are for devices such as
    scanners and printers.
    Powered hubs are for devices like keyboards and hard drives.

    If you want to argue about what I said, please write to the owner of the
    website as that's where my info came from.
     
    Richard, Dec 26, 2003
    #7
  8. fros

    -= Hawk =- Guest

    So why'd you try and answer him since you don't have even
    the BASIC answers?
    A switch can be compared to an intelligent hub, it creates
    'virtual circuits' between two devices on a network segment
    allowing the two devices to communicate utilizing the entire
    available bandwidth. It has nothing to do with television.
    A router determines if traffic belongs on the local network
    or if it needs to be ROUTED to another network segment.
    Routers connect different network segments together.
    They have nothing to do with radio scanners.
    You've described a USB hub, and incorrectly decided that this
    is what the OP was asking about because you've no idea what
    an ethernet hub is.
    Hubs, powered or unpowered are interconnectivity devices
    that allow devices and computers on the same network
    segment to communicate with each other. They do not
    create the 'virtual circuits' and are much more inefficient
    that switches. Hubs in the connotation that the OP was
    discussing (i.e. their comparison to routers) have nothing
    to do with scanners or keyboards, they may have something
    to do with printers and hard drives but not in the way you
    describe or can conceive.
    If I want to laugh at your inability to understand ANYTHING you're
    trying to discuss is it ok if I don't?
     
    -= Hawk =-, Dec 26, 2003
    #8
  9. fros

    -= Hawk =- Guest

    You might check out some picture books, I hear the pop-up ones
    are QUITE exciting, as they may be the only thing 'written' at your
    level of intelligence.
     
    -= Hawk =-, Dec 26, 2003
    #9
  10. fros

    why? Guest

    So you still didn't cover that point.
    That's still a lot of crap, not matter where it came from.

    Me
     
    why?, Dec 26, 2003
    #10
  11. fros

    Meat-Plow Guest

    It just doesn't get any more St00pid than this.
     
    Meat-Plow, Dec 26, 2003
    #11
  12. fros

    KinCornCarn Guest


    This is getting a bit confusing... I don't think you really
    understand what you're speaking of here... It sounds more like you're
    talking about USB connectivity, or peripherals when you talk about
    hubs and switches. Sounds like a basic misinterpretation of the
    question.. When you get into routers... your definition is way
    off...

    A router is a machine with a revolving vertical spindle and cutter
    for milling out the surface of wood or metal.
     
    KinCornCarn, Dec 26, 2003
    #12
  13. fros

    fros Guest

    Since one of the original questions was unanswered I thought I'd try and
    post it again:
    "Then, I saw a professional IT person setup a small LAN with 2 machines for
    now,
    but with more to be added in the future, but he first cabled the 2 machines
    into a 4 port hub, and then the hub into a 4 port router, & the router to a
    modem.
    * I'd like to understand why it would be done this way?"

    Since the machines could be directly connected to the router, what are the
    benefits of going through a hub first?
     
    fros, Dec 26, 2003
    #13
  14. fros

    ralph Guest

    For future scalability, more hubs can be added to the router.
     
    ralph, Dec 26, 2003
    #14
  15. fros

    why? Guest

    Adding computers above the number of ports on the router. Many routers
    can handle 256 PCs. However with only 1 or 4 ports it's a bit difficult
    to fit in that many cables :) so the number of connections is simply
    increased.
    None, in fact the router is more likely to be a switch on the LAN side
    and give better performance.

    It makes more sense to put servers on the router/switch and PCs on a
    hub, if that's the reason.

    Without knowing if your hub is a repeater or a switch of course......

    A hub i.e. repeater if it is in this case, connects all systems together
    on a common segment . This introduces device contention, on a repeater
    only one device can talk/listen at a time.

    If there is heavy PC/PC access i.e. non Internet access then a switch
    would be better. Say there are 3 PCs in the repeater , one is a server
    file/print whatever and 2 PCs. If the server and 1 PC is generating a
    lot of traffic , and the 3rd PC is trying to use the Internet
    performance could be poor. (This is whare half/full-duplex comes into
    play)

    However if the hub is a switch, a switch sets up a dedicated link to the
    server/PC and that traffic does not interfere with the 3rd PCs Internet
    access (it's directed to the router) , that (Pc/server) traffic does not
    hit the router either.

    http://www.webopedia.com/TERM/s/segment.html
    http://www.webopedia.com/TERM/c/contention.html
    http://www.webopedia.com/TERM/r/router.html
    http://www.webopedia.com/TERM/s/switch.html
    http://www.webopedia.com/TERM/r/repeater.html
    http://www.webopedia.com/TERM/H/hub.html
    http://www.webopedia.com/TERM/f/full_duplex.html

    Me
     
    why?, Dec 26, 2003
    #15
  16. fros

    bigfatdodo Guest

    You said the modem was connected to the router, perhaps the only reason for
    this router is to'supply internet access or a dial in connection to a main
    office to the LAN, in such a small lan there is no point in using a router
    between the two workstations. referencing the OSI model, the lower three
    levels

    3 - Network (wher IP from tcp/ip resides)
    2 - Data Link (Hardware adressing / mac adress)
    1 - Physical (wiring etc.)

    a Hub works on the 1st layer, as a physical device just transporting
    electric signals out to all its ports, no intelligence is found here besides
    the 'powered'or 'active' hubs wich 'resend' the signal in order to extend
    the maximal cable length. for 100baseTX this is 100 metres, an unpowered hub
    is just a device on the total length while an active hub allows for 100
    metres per port since the data is resend.

    A switch works on the 2nd layer, it actually learns the attached mac
    adresses of the computers/devices per port. so when device A sends data to
    Device B, the switch knows to wich port the data needs to be sent, this
    virtual switching allows device C to send to device D at the same time at
    full speed. A hub would sent the packet from device A to all devices so that
    device C would have to wait before sending its data to device D.

    The router, in the end, works at the 3th level and makes routing decisions
    based on the target ip address in the packet header. The router knows to
    which router or which interface to send this packet so that it will arrive
    at its destination. (that should explain a lot ;-) ).

    192.168.222.254 \ / 10.0.0.254
    A ---------------------------- O -------------------------- B
    \ 192.168.222.3 | \ 212.8.23.231 |
    \ 10.0.0.34
    |
    D- 10.0.0.32
    C -212.8.23.234

    In the picture above, the O is the router, this router has three interfaces,
    one in the 192.168.222.0 network, one in the 10.0.0.0 network an one in the
    212.8.23.0 network.

    Device A does not know that devices B,C and D exist, it does not know the
    hardware adresses of these devices. Whenever device A needs to communicate
    with another device it needs to send its packets to the router, the router
    knows how to reach the destination and routes the packet to the correct
    destination. if Device B wants to send a packet to Device D, it's considered
    local traffic, on the same subnet so the router does not have to do
    anything.

    Very brief, very short and probably raises more questions than it seems to
    answer. but these are mainly the differences between these devices.
     
    bigfatdodo, Dec 26, 2003
    #16
  17. fros

    John Henry Guest

    What we've got here, Meat-Plow, is a...FAILURE to communicate
    I recall saying this sometime about mid-May 1999. Never underestimate the
    power of pedo st00pidity.

    --
    John Henry
    -Now playing: Winamp stopped
    http://www.lowgenius.com - if it's not one thing
    http://www.rspw.net - it's the other.
    What have I become, my sweetest friend?
    Everyone I know goes away, in the end
     
    John Henry, Dec 27, 2003
    #17
  18. fros

    -= Hawk =- Guest

    It's a 'four port router' ("and then the hub into a 4 port router")
    i.e. it's already a switch, the dumb hub is extraneous.
     
    -= Hawk =-, Dec 27, 2003
    #18
  19. fros

    Frank Guest

    None Hubs are outdated.
     
    Frank, Dec 27, 2003
    #19
  20. What website might that be? Specialolympics.org?


    Ryan Lankford
    http://www.ryan-lankford.com

    "Donkeys can talk, people can fly, and a man named Jesus lives in the Sky!"

    "Gun control? It's the best thing you can do for crooks and gangsters.
    I want you to have nothing. If I'm a bad guy, I'm always gonna have a gun.
    Safety locks? You will pull the trigger with a lock on, and I'll pull the
    trigger. We'll see who wins."-- Sammy "the Bull" Gravano

    "For a few brief moments, America held the hope that O.J. Simpson had murdered Katherine Harris."--Bill Maher

    "I'll have those ni**ers voting Democratic for the next 200 years."--Lyndon B. Johnson
     
    Ryan Lankford, Dec 27, 2003
    #20
    1. Advertisements

Ask a Question

Want to reply to this thread or ask your own question?

You'll need to choose a username for the site, which only take a couple of moments (here). After that, you can post your question and our members will help you out.