Attaching second PC to router with one port

[Tom B.]

Hi everyone

I hope someone can help.

We have two computers, both running XP Pro SP2. The first computer
accesses the Internet through a router/ADSL modem connected by Ethernet
(i.e. Cat5 cable running from the PC's NIC to the back of the router.
The router has its own power supply).

What we'd like to do is allow the second PC to share the first PC's
Internet connection. I understand that all we'd need to do is plug the
second PC into the router, but here's the problem: the router only has
one Ethernet port.

What do I need to do to connect the second PC to the router? After a
little research, I found out about hubs and switches. But what's the
difference between a hub and a switch and which one would I need to buy?
Also, what kind of cable would I need for the second PC?

Advice greatly appreciated

Tom

 

[Steve Winograd [MVP]]

Hi everyone

I hope someone can help.

We have two computers, both running XP Pro SP2. The first computer
accesses the Internet through a router/ADSL modem connected by Ethernet
(i.e. Cat5 cable running from the PC's NIC to the back of the router.
The router has its own power supply).

What we'd like to do is allow the second PC to share the first PC's
Internet connection. I understand that all we'd need to do is plug the
second PC into the router, but here's the problem: the router only has
one Ethernet port.

What do I need to do to connect the second PC to the router? After a
little research, I found out about hubs and switches. But what's the
difference between a hub and a switch and which one would I need to buy?
Also, what kind of cable would I need for the second PC?

Advice greatly appreciated

Tom

Get a switch. If the switch has an uplink port, connect that port to
the router. If the switch doesn't have an uplink port, connect any of
its ports to the router. Connect both computers to the switch. Use
regular Cat5 cables for all connections.

Hubs are pretty much obsolete. Switches offer better throughput for
multiple computers and don't cost much, if any, more than hubs.

A hub transmits all incoming packets to all of its ports, so each
computer sees packets addressed to every other computer. A switch
only transmits incoming packets to the computer that is to receive
them.
--
Best Wishes,
Steve Winograd, MS-MVP (Windows Networking)

Please post any reply as a follow-up message in the news group
for everyone to see. I'm sorry, but I don't answer questions
addressed directly to me in E-mail or news groups.

Microsoft Most Valuable Professional Program
http://mvp.support.microsoft.com

 

[Bob Willard]

Hi everyone

I hope someone can help.

We have two computers, both running XP Pro SP2. The first computer
accesses the Internet through a router/ADSL modem connected by Ethernet
(i.e. Cat5 cable running from the PC's NIC to the back of the router.
The router has its own power supply).

What we'd like to do is allow the second PC to share the first PC's
Internet connection. I understand that all we'd need to do is plug the
second PC into the router, but here's the problem: the router only has
one Ethernet port.

What do I need to do to connect the second PC to the router? After a
little research, I found out about hubs and switches. But what's the
difference between a hub and a switch and which one would I need to buy?
Also, what kind of cable would I need for the second PC?

Advice greatly appreciated

Tom

If you mostly want to have both PCs share the internet, then any old hub
(including a 5$ second-hand hub) will suffice. But if you also want to share
files, you may be frustrated with the low performance, since most old hubs
are 10 Mb/s (i.e., ~1 MB/s file transfer rate); for file sharing, a 100 Mb/s
switch will be better. Also, with a hub, your ISP must supply an IPA (that's
an address) for each PC; some ISPs won't, some will, and some will but only
for an extra monthly fee.

Use the same cable type you currently have; you'll need 3: hub/switch (uplink
port) to router/modem, hub/switch (downlink port) to PC-a, and hub/switch
(downlink port) to PC-b.

If the router/modem acts as a firewall, then you're done; if not, then you
will be better protected by getting a SOHO router instead of the hub/switch,
since such routers do NAT and filter out most unwanted inbound traffic. The
router/modem furnished by my cable ISP is not a firewall, so I use a real
router behind that router/modem to keep the gremlins out.

All in all: you should probably buy a router.

 

[Tom B.]

Get a switch. If the switch has an uplink port, connect that port to
the router. If the switch doesn't have an uplink port, connect any of
its ports to the router. Connect both computers to the switch. Use
regular Cat5 cables for all connections.

Hubs are pretty much obsolete. Switches offer better throughput for
multiple computers and don't cost much, if any, more than hubs.

A hub transmits all incoming packets to all of its ports, so each
computer sees packets addressed to every other computer. A switch
only transmits incoming packets to the computer that is to receive
them.

Hi Steve

Thanks for that very informative and lucid answer!

Kind regards,
Tom

 

[Tom B.]

If you mostly want to have both PCs share the internet, then any old hub
(including a 5$ second-hand hub) will suffice. But if you also want to
share
files, you may be frustrated with the low performance, since most old hubs
are 10 Mb/s (i.e., ~1 MB/s file transfer rate); for file sharing, a 100
Mb/s
switch will be better. Also, with a hub, your ISP must supply an IPA
(that's
an address) for each PC; some ISPs won't, some will, and some will but only
for an extra monthly fee.

Use the same cable type you currently have; you'll need 3: hub/switch
(uplink
port) to router/modem, hub/switch (downlink port) to PC-a, and hub/switch
(downlink port) to PC-b.

If the router/modem acts as a firewall, then you're done; if not, then you
will be better protected by getting a SOHO router instead of the
hub/switch,
since such routers do NAT and filter out most unwanted inbound traffic.
The
router/modem furnished by my cable ISP is not a firewall, so I use a real
router behind that router/modem to keep the gremlins out.

All in all: you should probably buy a router.

Hi Bob

Thanks for the help but I'm a little bit confused. How do I tell if I
need a router or not?

I have an "Enable NAT" setting in the router/modem's web interface.
Ipconfig says:

Connection-specific DNS Suffix . :
IP Address. . . . . . . . . . . . : 192.168.1.3
Subnet Mask . . . . . . . . . . . : 255.255.255.0
Default Gateway . . . . . . . . . : 192.168.1.2

192.168.1.2 is the address of the router/modem. So is this a real router
or do I need something else in your view?

Thanks again