Yes, a lovely customer service representative from NTL who would kindly supply you with a proper eathernet router (yes, it's a router not a modem) or a smiling shop assistant who would sell you one.
Cheers.
P.S. MoDem stands for modulator/demodulator and used for converting digital signal to analog and vice versa on a basic level plus other useful bits like dialing a phone, since your line is digital and you don't need to dial a phone line you wouldn't need a modem. Although anything is possible in this freaking world

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