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nevzus
Jun 12, 2008, 04:54 PM
Hello,
I have Dynex - 5-Port 10/100 Ethernet Switch to connect two computers to internet through a cable modem (linksys). I have used this switch at work, with much faster internet connection, and it was working fine. At home I was using a router (with brand name USR8054) and it was working fine until it is broken (not powering anymore). I brought the switch to use at home but when I connect two computers, only one of them works. I power down, up the modem, open computers, but I can never get both computers work at the same time.
What can be the problem? Thanks for your inputs.
Nevzat.



Queso
Jun 12, 2008, 04:56 PM
Sounds to me like your Internet Service Provider uses MAC restriction to ensure that only one computer at a time can use the Internet. Your old router only appeared as one MAC address to the ISP with all other computers hiding behind it.

miniConvert
Jun 12, 2008, 05:02 PM
Either that or both computers are now using the same IP address, or are not receiving any IP address at all (most home routers handle assigning local IP addresses).

nevzus
Jun 12, 2008, 05:33 PM
Thanks.
How can I solve it if it is IP problem? I will call the internet provider, which is cox, if they have MAC restriction..
Nevzat.

farbeyond
Jun 12, 2008, 05:37 PM
I'd try giving your 2 comps static IP's. . . Or looking at the PC that does have an IP and giving the second machine an IP in the same subnet. I'm not sure if your router has DHCP enabled, if it did you'd probably be working. Let us know how you get on.

Consultant
Jun 12, 2008, 06:01 PM
Get a router.

I suggest
http://www.apple.com/wifi/

Airport Extreme Base Station with Cat 5e or Cat 6 cables for gigabit ethernet transfers between computers on your network.


I'd try giving your 2 comps static IP's. . . Or looking at the PC that does have an IP and giving the second machine an IP in the same subnet. I'm not sure if your router has DHCP enabled, if it did you'd probably be working. Let us know how you get on.

The modem is not a router.

theBB
Jun 12, 2008, 06:24 PM
You need a router, not a switch.

farbeyond
Jun 13, 2008, 02:41 AM
Makes no difference if you use a switch or a router, the only difference between them being is a switch has a routing table it uses to look up where traffic needs to be routed to - this cuts down on traffic on your network. A router just sends out packets to each port on the router so you end up with more traffic. In a home set-up this really makes no difference....

Queso
Jun 13, 2008, 03:45 AM
Makes no difference if you use a switch or a router, the only difference between them being is a switch has a routing table it uses to look up where traffic needs to be routed to - this cuts down on traffic on your network. A router just sends out packets to each port on the router so you end up with more traffic. In a home set-up this really makes no difference....
You are confusing a router with a hub. Routers forward packets between network segments according to a configured or learned set of rules (the routing table).

And I should know, I'm a CCNP (http://www.cisco.com/web/learning/le3/le2/le37/le10/learning_certification_type_home.html) ;)

ChrisA
Jun 13, 2008, 10:42 AM
..I was using a router ... and it was working fine until it is broken .... I brought the switch to use at home but when I connect two computers, only one of them works.

So what does this tell you? Routers work, switches don't. Get another router.

ChrisA
Jun 13, 2008, 10:52 AM
Makes no difference if you use a switch or a router, the only difference between them being is a switch has a routing table it uses to look up where traffic needs to be routed to - this cuts down on traffic on your network. A router just sends out packets to each port on the router so you end up with more traffic. In a home set-up this really makes no difference....

The above has "scrambled terminology" and is basically wrong. I can decipher what is meant but the terms are all used the wrong way.

The key to understanding this is "layers". First you have Ethernet then you have IP. IP is transported over Ethernet but it can use other methods too such as WiFi. Both switches and hubs work at the Ethernet level. Routers work at the IP level. They do different jobs

As to how the devices work internally you don't really need to know except that routers have "routing tables" and switches have "spanning tables". Switches don't "route" they "switch". All these terms have exact technical meanings and you can't use them casually in a conversation about networking

Queso
Jun 13, 2008, 12:04 PM
CAM table (Content Addressable Memory) or MAC forwarding table are the correct terms. Spanning-Tree is something different, more of a network protection mechanism to prevent broadcast loops from overwhelming two or more switch CPUs with datagrams that are continually forwarded between the switches.

Anyway, I'm getting into geek territory again, so I'll leave it now :)

nevzus
Jun 13, 2008, 02:21 PM
Hello All,
Thanks for all the inputs. I called my internet provider and they actually confirmed they have MAC address restriction. So, switch will not work because I have only one IP address. Only way to get around it is using a router.
I did not know about this "MAC restriction" before so I was thinking I am doing something wrong. But now I learned.
Thanks all again.