Comcast: multiple IPs?

[space-time]

I wonder if I connect a switch (not router) to the cable modem and then I plug in various devices, will they all get IPs directly from comcast? I want to avoid dealing with NAT and port forwarding if possible. I think if I could get 3 IPs form comcast I would be very happy.

[GGD]

I haven't looked into this for a few years, so I don't know for sure that they still will do this, but in the past they offered their "home networking" which was multiple IPs, and they charged $5/month for each additional "computer" (IP address) that you wanted to connect.

This was mainly for people who didn't understand what a router is and how inexpensive they are and wanted to hook up multiple computer. Or maybe for people who did understand everything and needed multiple WAN IP addresses rather than NAT everything behind one WAN IP.

[space-time]

yeah, something along those line I saw when I googled around, but most posts were quite old. I need to call them and ask.

[Filliam H. Muffman]

I don't really understand why you need separate IP addresses, could you expand on that?

Some modems can act as routers, but it is not a standard configuration. Most of the time they set it up as one IP per modem and that usually means one bill per IP ($43/mo. after the new customer discount period ends).

[AllGold]

Comcast will be happy to take a bunch more of your money and give you some additional IPs. But on their standard plan, nope just one IP.

[Doc]

> I wonder if I connect a switch (not router) to the
> cable modem and then I plug in various devices, will
> they all get IPs directly from comcast?

Not unless the modem is also a router with NAT.

Why wouldn't you just buy a router with a built-in 4-port switch?

[space-time]

Doc wrote:
...

Why wouldn't you just buy a router with a built-in 4-port switch?

because I had some issues with some VOIP boxes and some iChat issues when using NAT?

Sure, I may not be setting NAT correctly on my router, but when I have multipled VOIP boxes and multiple computer wanting to use iChat behind the same router, things could get quite messy.

So right now I have this setup:

Cable -> Modem (Motorola) -> VOIP (Linksys/GIZMO, this gives me a lot of touble with NAT) -> Router

and the the router I have several WiFi devices (2 macs, sometimes 1 XP i bring home from work, and an iTouch), and then I have a Packet8 VOIP box and a printer (but the printer does not need to access the outside world).

most of the time I use Skype instead of iChat because I never had NAT issues with Skype, but sometimes I need iChat for screen sharing to help troubleshooting

[Doc]

> when I have multipled VOIP boxes and multiple
> computer wanting to use iChat behind the same
> router, things could get quite messy.

Having multiple public IP addresses from your ISP wouldn't fix it. The data would still be going through th same pipe with the same priorities.

You probably need a router with QoS administration if you have multiple VOIP sessions going simultaneously and experience slowdowns or loss of service from it.

Depending upon what specific model router you've got, you may be able to install 3rd party firmware to enable QoS.

[Filliam H. Muffman]

This is one of the reasons that true Net Neutrality is important. The cable companies have been known to mess with the delivery of VOIP packets from people using 3rd party VOIP solutions.

[M A V I C]

If you think comcast is messing with the connection, you can try http://us.sharedband.com/ I think they'll let you use it with just one connection. You don't get the bonding benefits, but it works on the IP layer so you have a connection that's immune to any traffic shaping comcast tries to impose.