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31

There's a standard protocol for that, called the Spanning Tree Protocol. As the name suggests, it works by building a spanning tree of the network — a subset of the network that includes all nodes but contains no loops — and then disabling any ports that aren't part of the spanning tree. If a link in the spanning tree fails, e.g. if someone unplugs a ...


18

A hub is the simplest hardware device that is used to interconnect equipments. It provides network ports from which he reads packets and duplicates them to all other ports. The switch (layer II) is an enhanced hub. The simplest switch can decide on which port to send a received packet so as to not disturb a sub-network where no one is interested with this ...


16

Note that the USB Specification somewhere says that devices that are only connected but haven't "authorized" yet may only drain 100 mA instead of the usual 500 mA. It could be that your USB Hub simply does not supply the full 500 mA if it isn't connected to a PC, to be in line with the standard. Wall chargers ignore that as they aren't USB devices but ...


13

None of the answers quite answer the title question. How to “restart/repair” a USB port? There are three ways to "restart" a particular USB port: Reboot the computer. Or ... Unplug, then re-plug, the physical device connected to the port. Or ... Disable, then re-enable, the USB Root Hub device that the port is attached to. In Windows you'd do ...


13

No, not entirely (or none I've ever seen), but you can get managed and smart switches to perform Port Mirroring, which will give you all the traffic on the switch on one port. Some folk believe that you can force certain types of switches to send out all the frames they receive on all ports, using an MAC or ARP flood attack, but I've no experience with that ...


12

With just two devices, a hub is sufficient. When you have just two machines to connect, why the network device? go point-to-point. I am guessing you want to connect more devices later. Collisions will matter at that time then (and you cannot go PtP then either). These days switches and hubs do not have a lot of cost differential. You might in fact get a ...


11

In the case that both hosts that have mutual connectivity... The blackbox must be a router if any of the following are true: The two hosts have IP addresses in different IP networks. A broadcast ping (ie: 255.255.255.255) from one host does not increment traffic counters on the other host. Either hosts' ARP table does not have an entry for the other ...


9

I think with just two devices, a cable is sufficient. If none of the devices has Auto-MDIX you'll need a crossover cable.


8

Check: Transform a USB hub into the ultimate DIY gadget charger I'm talking about a standard USB hub--those little accessories that multiply one of your PC's USB ports by a factor of four, five, six, or even seven. I took a spare seven-porter--the Belkin F5U701 ($20)--plugged its included AC adapter into a nearby wall outlet, and started loading it up ...


8

I use an old hub for network troubleshooting as well. They're hard to come by these days. There appear to be a few on Amazon and you may find some on ebay as well. Make sure to read the tech specs carefully to make sure you're actually getting a hub, as opposed to a switch. ...


7

No, you can't do that. You need something smart in between to share the printer. Either one of your PCs or a print server. You don't need to replace your whole router, you can get a device like this for example that you can just plug into one of the wired connections of your existing router. http://www.netgear.co.uk/usb%5Fprint%5Fserver%5Fps121.php USB ...


7

If you're tying up one port to only really gain two, why do it? 4 port hubs are common, and an seven port hub is simply a doubled up four port with one port gone because you're using it to extend the four port again. It's cheap manufacturing.


6

If your application for a hub is "inserting a protocol analyzer into a network connection", the modern answer is a switch that supports a monitor mode, in which one switch port is configured to emit all packets to and from another specified port. The Netgear GS108T (the T is important) is an example of a small switch that does this. Since, as someone else ...


5

Amazon to the rescue. Unfortunately it's a special product now (people who want them really want them and can't use something else) so the prices may be higher than you expect. EDIT: Also you will NOT get a gigabit hub. You won't find PCI-E video cards to use on a 386 motherboard, either...:)


5

To answer your question, the only times a hub works better then a switch is when you have bad hardware or incompatible hardware. The first is relatively easy to test, but incompatibilities can be difficult to find. I have run into switches that just don't like communicating with particular switches. Try switches that are different models and manufactures and ...


5

If you mean like this: Then yes it is technically possible, but there are drawbacks: But if one or both devices draw power FROM the USB header then the wheels fall off. A device connected to the USB header will hang onto the connection even if the software for it is shut down and the device is "powered off." See: ...


5

I believe the key here, is that he stated it's a passive 2.5" hard drive enclosure. That means that it may require two powered ports to have full power. The hard drive just may not be getting enough power. Is the hub plugged into a power outlet Does the usb cable have two ports? And are both being plugged into the usb hub? Does system Profiler see the ...


5

First, Gigabit Ethernet doesn't allows hubs. When the IEEE first defined GigE, they briefly had a spec for how a GigE hub should work, but no one ever shipped one, and the IEEE quickly deprecated the spec and recommended that GigE always be switched. (Trivia note: This means that GigE is technically not CSMA/CD.) You can still buy 100BASE-TX hubs if you ...


5

Smart switches that implement the Spanning Tree Protocol (STP) will attempt to break loops by selectively shutting down ports if they detect their own BPDU packets getting back to them. In addition, their security protocols may shutdown ports where any BPDU was detected, if said port was designated to be single-terminal only. That said, pure repeaters and ...


5

In order for you to see any performance increase by plugging in two cables between the switches, you need to set up something called link aggregation, which will increase throughput between the two switches, and also provide redundancy if one of the links fail. Link aggregation is not supported by unmanaged switches, you need a managed or websmart switch. ...


4

Five port hubs Six port hubs Three probably isn't enough to justify making a product when 4 ports are readily available, so I'm sure that's why companies skip them. 8-port is a lot of ports, I would estimate the demand is small. Five and six port hubs do exist though.


4

Connect another switch to your current switch. Either by cascading switches, where the uplink (if present) of the new switch is connected to a port on the original switch. Or by using stackable switches.


4

If you've only got two devices, why not just use a crossover cable? Some ports will even auto-switch Rx & Tx in hardware, meaning you could just use a plain old CAT-5 cable. It's worth trying that first; you may not need to buy anything.


4

Ive run 3 external hds off a Belkin wall-powered hub and gotten the same speed as a direct connection, however my hard drives were all wall-powered as well. As a rule of thumb, it's definitely better to get powered USB hubs for any hard disk usage or heavy data access (bigger thumb drives, etc), while self/computer powered hubs are usually for ...


4

You should be fine with a USB extension cable as long as you remain within the limits of the specification, which if I remember rightly states devices should be no more then 5m (cable length) apart. So if your existing cable is 1m long, you could add a 2m extension and still be well within spec.


4

You'd need a router of some sort to do the bandwidth management you're talking about. If you already have a DSL/Cable router, you might be able to use Tomato or DD-WRT to get the function you seek. But that's not for the faint of heart and may wind up destroying your router.


4

Can one plug 'too many' peripherals into a USB port? Most definitely. There is always a power limitation somewhere. In general, most USB ports provide 500mA (500 milliamps) of power output per port. I'd check the peripherals you are plugging in for the required power draw of each and total it up.


4

Hub is not a Hub, it is a switch with different segment VLANs configured on each interface. Router is stripping the 8021Q tags and allowing routed communication back across to a single vlan. If the router were replaced with a switch you wouldn't see the communication to and from A - B, A- C. The reason why you are getting destination unreachable is ...


3

It's by standard as explained here: https://en.wikipedia.org/wiki/USB_device#System_design You can't have more than 127 devices (hub inclusive) connected to a single host controller. Now: the host controller+3 hub (1st layer)+18 hub (2nd layer) = 22 devices that DON'T appear as disk devices. 127 minus these 22 USB devices = 105 devices that can be managed ...



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