Should I Enable RIP of ADSL modem?

[sia]

My Asus ADSL router (I have a 64 kb/s connection) has an option RIP (Routing Information Protocol?). I don't know http://www.shareazasecurity.be/forum/images/smilies/icon_e_ugeek.gif weather enable it or leave it disable. I read about it in Cisco (http://www.pulsewan.com/data101/rip_basics.htm/url). Please tell me to enable it or not. Thank you.
http://www.shareazasecurity.be/forum/images/smilies/icon_arrow.gif Does this option need ISP support?

[yawningdog]

You don't need a routing protocol unless you're going to establish your own IP scheme. If you're going to be using more than one computer on this connection then you probably need to enable RIP. That is, if the modem doesn't perform layer 3 switching. Mess around with it a bit and post what you find, I'm curious that this is an option in a modem and I'm interested to see what you find.

[sia]

I have two PCs connected to internet via ADSL router. One is connected via Ethernet LAN and the other via USB port. Two computers are also connected to each other in this way. But only one PC can connect to internet at one time.

[yawningdog]

Ditch the USB connection, enable RIP, and connect both pcs to the ethernet port through a switch. Make sure you have DHCP services set up somewhere, hopefull at your modem.

[sia]

I don't have switch or hub and one of my PCs doesn't have Ethernet port.

[Erik]

RIP won't do anything for you here. It is used between routers, and they all need to be configured to work together for updates. You only have one router in your network, and your ISP already knows you are there (not that you would advertise to them anyway as RIP is an interior routing protocol). Besides which this is most likely RIPv1 which is an outdated and basically dead protocol.

It would only possibly be useful if you had multiple internal subnets that you needed to route between, and had multiple routers all configured to communicate the updates. Having multiple computers has nothing to do with needing MLS (Multi Layer Switching or Layer 3 Switching) or a routing protocol. In a typical network (especially true in home networks) all of the computers on on the same subnet. That means only layer 2 switching (ie based on MAC address) is needed internally. Any traffic for another network will use the default gateway because it is destined for an external network (otherwise known as the internet).

That said I have setup networks with multiple subnets which worked perfectly fine without any routing protocol. Unless you are growing large enough to have multiple different routers which are not directly connected (or even just have an interface in each network) a routing protocol just adds to the network traffic with no real gain. Remember that by default a router will know how to reach any network that it is directly connected to. All other traffic will be pushed through the default route. So unless you have a subnet or different network involved that is not directly connected or reachable via the default route you have no need for any routing protocol.

[sia]

Thanks Erik.