Cisco 2600 to cable modem setup - how?

[WannaFly]

I just acquired a 2600 series cisco router, it only has a T1 CSU/DSU WIC card in it.
What i'm trying to figure out is what I need to get to be able to connect it to my cable modem at home - I assume a serial WIC(cant find the right one though), and an adapter to change the serial to ethernet - is that correct?

Also, on the serial ports i have only set them up with static IP's, will tehy support DHCP? (I'll keep looking for this awnser)

Thanks.

 

[bgroff]

No! The whole point of a router is to go from serial to ethernet. If you wanna connect that router to your cable modem, I hope you got a 2611 or 2621 (or even a 2613). Because you need something with 2 LAN ports. Otherwise you have to start getting tricky and do a "router on a stick" type scenario. If this is the case, it will work perfectly fine as a cable modem router.

BTW, if you're truely desparate to hook up the router to your cable modem, Cisco does make an ethernet WIC. Sometimes you can even find them on ebay.

 

[WannaFly]

hmm i dont quite understand the 'router on a stick' scenerio, but if it will work, why not?

I'll look into getting an ethernet WIC though.

I dont see why it shouldnt be done like this though, although i wont be terribly disappointed if i cant use it as a cable modem router.

 

[bgroff]

Um, trust me. A T1 WIC is designed to connect to a T-1. That's a special digital telephone line. Its voltages and line codings are WAY different than ethernet. So unless you have the strangest cable modem ever, with a special T-1 port on it, it doesn't work like that.

 

[WannaFly]

Originally posted by: bgroff
Um, trust me. A T1 WIC is designed to connect to a T-1. That's a special digital telephone line. Its voltages and line codings are WAY different than ethernet. So unless you have the strangest cable modem ever, with a special T-1 port on it, it doesn't work like that.

Thanks for the info, but I know that - that is why i was asking what I need do/get connect it to my cable modem.

 

[azev]

get an ethernet wic and it should solve your problem

 

[cmetz]

WannaFly, you need a second Ethernet port to connect to your cable modem. There actually is I believe an Ethernet WIC, but it's gotta be painfully slow. You need to buy an Ethernet NM. Your choices are basically a NM-1E, NM-2E2W, NM-1FE, NM-2FE, NM-2FE2W, or NM-4E (there may be others I haven't seen). An "E" is a 10Mb/s half-duplex Ethernet interface, no VLAN support. An "FE" is a more modern 10/100 half/full Ethernet interface that can do .1Q VLANs. The W is more WIC ports, which you probably don't care about. Not all of those might be usable on the 2600 platform. You might, oddly enough, find that more ports or better Ethernet is cheaper, it all depends on supply and demand. But regardless, you're going to pay real money for this module.

You may be able to trade and/or sell your T1 WIC towards this. If you don't have a T1, it isn't doing you any good.

 

[bgroff]

Originally posted by: cmetz
WannaFly, you need a second Ethernet port to connect to your cable modem. There actually is I believe an Ethernet WIC, but it's gotta be painfully slow. You need to buy an Ethernet NM. Your choices are basically a NM-1E, NM-2E2W, NM-1FE, NM-2FE, NM-2FE2W, or NM-4E (there may be others I haven't seen). An "E" is a 10Mb/s half-duplex Ethernet interface, no VLAN support. An "FE" is a more modern 10/100 half/full Ethernet interface that can do .1Q VLANs. The W is more WIC ports, which you probably don't care about. Not all of those might be usable on the 2600 platform. You might, oddly enough, find that more ports or better Ethernet is cheaper, it all depends on supply and demand. But regardless, you're going to pay real money for this module.

As far as 10 Mbit Ethernet not supporting VLAN tagging that's a *buzz*. In newer IOS releases (for sure 12.2T, maybe 12.2) there is support for VLAN tagging on the 2600 platform, including 10Mbit ports. As far as the Ethernet WIC being painfully slow, i doubt it would be that bad. At worst case, you'd might be bus limited to 4mbits. At best case, there would be no problem... Oh, and BTW, you can't put a network module with ethernet/fast ethernet ports and WIC slots into a 2600. Its not supported. Those are strictly for the 3600 series...

 

[bgroff]

I was just looking a little closer at the Cisco website, and the WIC-1ENET (ethernet WIC card) is only supported on the 1700 series routers. So this is a no go for the 2600! Looks like you have the router on a stick (VLAN tagging) or another ethernet port via the network module slot (the NM-1E is going for under $200 on fleebay).

 

[cmetz]

bgroff, what's the MTU when you configure 802.1Q tagging on the 2600's Ethernet0/0? I didn't think the LANCE chip in there could handle any frames >1500, which was why it used to be FastEthernet only. (it could do ISL, but... ick) Tagging is fine, but you don't want to be stuck with MTU=1496 usable payload if you can avoid it. Oh, and that still means that WannaFly has to come up with a switch that can break out tagged VLANs... which may well cost what an Ethernet NM would cost anyway.

 

[cmetz]

bgroff... hey, learn something new every day. On my lab 3640/NM-2E2W, 12.2(16) mainline, it seems to work fine, and MTU 1500 on the subinterface too. This makes my life easier - several times I've needed a router to be able to access multiple VLANs but haven't been able to do so on an Ethernet interface because that was Cisco's original restriction.

 

[bgroff]

Yup, Cisco finally got their act together and supported 802.1q on Ethernet. This feature is only available from the 2600 series up, no 2500s or 1600s are supported. As far as getting a switch that can handle 802.1q, it would be close but you can generally find some older 3com switches (say a SuperStack 1100) that will do the trick for way under $100.

Nice lab equipment btw... Back in the day, I only had piles of 2500s. Nothing fancy like 3640s!