Strange Behavior - Two IP addresses 1

[goombawaho]

Okay, here's the hardware setup before my question.

Arris TM502G cable modem (Wide Open West = ISP) connected to a Linksys unmanaged 4 port switch. From there, two CAT5 cables connected - one goes to a desktop computer and the other goes to a router. All the PCs behind the router have internet connectivity as does the standalone computer.

Here's the strange thing. The router has an outside IP address and the PC is getting another completely different IP address.

Why is the ISP providing two ip addresses through one modem??? I mean, this is why there was the boom in home routers - to share internet connections because most providers will only give you one IP address per modem (unless that modem is actually) a gateway. But this is not the case here, because it is providing two outside addresses.

This must be a mistake on the ISP's part to allow this.

 

[jimbopalmer]

You do not mention your ISP, but my ISP, CableOne, allows 3 devices to get 'external' IP addresses before a router is needed. Mind you, without a router, they may not have similar IPs all in one subnet, but they can all connect to the internet.

http://cableone.net/internet/plans.asp

click the ? next to Max Connected CPEs

If your ISP has similar advertised features, it is not a bug.

I tried to remain child-like, all I acheived was childish.

 

[goombawaho]

Actually, I DID mention the ISP Wide Open West. I don't think that's part of their service agreement, but I'll check into it.

 

[jimbopalmer]

http://www1.wowway.com/wow/__packaging__.aspx?ConIdent=38&RCView=Nothing

says WOW allows 3 IP addresses as well

"Value Internet - 768kbps* $34.99
WOW! Internet at 768kbps is perfect for checking e-mail & listening to music, and includes 5 e-mail accounts, 3 IP addresses and 10 MB of web space."

I tried to remain child-like, all I acheived was childish.

 

[goombawaho]

Wow - I never would have believed that. Now I have to re-think how I've set up his system and why it's acting flaky if two ip addresses are permissible.

Comcast will only give you the one external IP address as far as I know. Maybe I know nothing!!!!! Good work dude - a star pour vous.

 

[jimbopalmer]

There are lots of reasons to want a router, (privacy/security/wireless/NAT/network neighborhood) but it is nice of some ISPs to allow small groups without one.

(Comcast won't let me look at their offerings without a street adress, so we may never know)

I tried to remain child-like, all I acheived was childish.