Yes, your router would need to be the same speed or higher in order to take advantage of that capability. However, I should note that this is only going to affect transferring data internally on your network, and will not improve your internet speed, which is likely much lower than that (30-50 Mb/s at maximum is fairly standard for cable internet in most places). As your internet speed is still going to be the most likely bottleneck on your network, the 100 Mb/s transfer speed of your router is probably sufficient; upgrading won't hurt anything, but isn't really necessary either.