Buffering is a concept which has been around in networking since long. When we want to adjust the extra traffic without dropping it is known as buffering. The amount of holding the extra traffic varies from few micro seconds to seconds. More the holding time is deep the buffer is needed. The deep buffer means the extra traffic will be there in queue for few seconds and once the burst get cleared it will be served. The only advantage of deep buffer is to hold the peak burst for fraction of second but with this advantage we are getting one disadvantage also which is increase in latency.
The more we hold the data traffic the more latency will be. If this is the case how OEMs are claiming that deep buffer switches will help you to build low latency data centers. As per my understanding, deep buffers will help to build high latency data centers.