CM1100 Mult-Gig speed on Xfinity

Question

I have a CM1100 multi-gig modem.&nbsp; I purchased it at Costco a few years ago with the understanding that it supports multi-gig speeds.&nbsp; At the time, my Comcast speed was 1 gps.&nbsp; Recently Comcast upgraded my internet package to 1.2 gps.&nbsp; However, Comcast stated the CM1100 doesn't support multi gig.&nbsp; It caps out at 1 gps.&nbsp; Comcast said the CM2000 will support the 1.2 gps but not the CM1100.&nbsp;Does the CM1100 really not support multi-gig?&nbsp; And if it doesn't why is it being advertised as a multi-gig modem?&nbsp; Or is this a Comcast issue?&nbsp;&nbsp;&nbsp;

FURRYe38 · Answer

Since the LAN ports in back are rated at 1000Mpbs, you will max out at around 900 around 950Mpbs on a wired speed test. If LAGG is enabled you may see a bit more however you'll need a wifi router and or a PC that can take advantage of LAGG support from a modem. The CM2000 would better suited for anything over 1000Mbps. Be sure you have a router and a wired PC that can take advantage of 2.5Gb connection rates as well.&nbsp;

Pigg1e · Answer

I've got LAC-IEEE 802.3ad enabled on CM1100A and and router WAN aggregation is enabled on router.

Xfinity modem compatability page says the CM1100 is not compatabile with 1.2gps service. (Filter is 1.2gps). Xfinity is rating the CM1100 as Up to gps.

Netgear CM1100

Cable Modem

Incompatible based on filters

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FURRYe38 · Answer

I would presume the CM1100 may max out then.

What brand and model router do you have? Even if yoru router has LAG support, the LAN ports on the LAN side are problably 1000Mpbs as well so you'll not get anything beyond 900Mpbs on the LAN side. To get anything beyond 1000Mpbs, you need 2.5Gb connection rates at the modem WAN port, routers WAN and LAN port side and at the PCs ethernet adapter as well.

Pigg1e · Answer

Thanks for the reply --&nbsp; I've been testing it with Asus AX86u - supports 2.5 gps ports.&nbsp; All wiring is cat 6 and PCs have 2.5gps cards -- PCs transfer data at 2.5gps.&nbsp; So, I don't think it's on the router or PC side.&nbsp;&nbsp;&nbsp;I'm just curious if it's Comcast that's limiting the CM1100 or whether the CM1100 really doesn't support 1.2 gps.&nbsp; Costco's website says the CM1100 supports all cable internet speeds up to 2gps.&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;

FURRYe38 · Answer

From the data sheet:"• True Multi-Gig Experience—Link aggregation support delivers multi-gigwireless speed to with up to 2Gbps* download speed"&nbsp;I presume this is combined 2Gbps being 1Gb per each WAN port when LAGG is enabled. So 2Gb would be max. Depends on how data is being handled and flow from the modem to the LAG enabled router as well.&nbsp;

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CM1100 Mult-Gig speed on Xfinity

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