While both these connections perform at pretty high levels, a T1 line comes out marginally better when you compare T1 vs Ethernet across the performance criterion. This is because a T1 line is capable of providing “always on” Internet access. This is backed up by a robust service level agreement which can guarantee customers a specific time frame for repairs and a guarantee of performance as well. Thus, when it comes to T1 vs Ethernet, a business organization can easily look at cost and performance factors and then decide between the two.