On Tue, 29 Jan 2008 00:31:06 GMT, gecko <alpha@olympus.net>
wrote:

>I notice that Switches and Routers are being marketed to do what looks
>like pretty much the same thing. What is the difference? Why would
>one choose one over the other?
>
>Thanks
>
>Gecko

Rookie already mentioned logical difference, so I will talk
more about practical differences in making a buying choice.

Today most consumer grade routers have a switch built in.
You can use these routers as a switch and reserve the router
functionality for a later time, or make partial use of it if
it's a wifi router in access point mode to extend your
'sites wireless coverage. The main reason today for a
consumer to buy a switch instead is if it has a greater # of
ports, since the routers are commonly as inexpensive as the
switches if speaking of 100Mb, after a rebate in the US
they're as low as $0 to $15.

Gigabit is another story, gigabit routers are dropping in
price but still command a premium over 100Mb ethernet
versions.

The routing functionality itself is to segregate a LAN from
a WAN. Typically you don't want anything on the WAN
(*internet*) able to route to something on your lan, instead
using the IP port forwarding feature on the router. This as
a function of the NAT feature on a router means a router
gives you an additional layer of security over a switch.

Another feature of a router that is important to some is
that when connected to a modem and used with an ISP, many
ISPs only issue one IP address for their low cost
residential accounts. This would allow only one system to
connect to the internet if you don't have a router to do the
NAT and act as that one system, although today some modems
also incorporate a NAT and DHCP server feature so customers
could use a switch instead of a separate router.

Generally low cost switches are unmanaged, they pass
everything they are capable of. Managed switches are
significantly more expensive, and overkill for most
consumers' needs. With a router you do often have a basic
level of management features, moreso than with a switch.

I suppose ultimately given a low budget (who wants to spend
more than they need to?) the choice is basically:

Router - more security, configurability and features (some
features may vary per product, if your needs are unique more
research may be necessary).

Switch - cheaper if you want gigabit or more than roughly 5
switched ports.

Many people will first get a router, if their purchase came
after they already had broadband internet, then suppliment
that with a switch if they have need for more systems than
the router will support, OR if several of those systems are
situated a distance away from the router and it is easier or
more cost effective to run a single ethernet cable to a
remote switch and then cable from the switch to the systems,
rather than running several ethernet cables the longer or
more difficult path to these several systems (plus several
long ethernet runs can easily cost as much or more than the
price of a consumer grade switch). Those with wifi capable
client systems may instead pick a 2nd router for the remote
switch position so they have the option of using it in
access point mode to extend their wireless coverage as
mentioned previously.