While a seemingly techno geek comparison and discussion, PHY and MAC data transfer rates are commonly used sales and marketing tactics in many retail stores and consumer device packaging.
The PHY rate is essentially the physical layer and represents a theoretical performance rate of data transfer. The MAC rate, media access control, is essentially the rate of transfer that is most common. The PHY and MAC rates are rarely if ever the same. But the former is higher and theoretically more impressive. After all, more must be better, right?
The point of this pedestrian description is to point out that these discrepancies in performance are often misunderstood by most consumers adding to confusion, frustration and returns. While the PHY rate is considered better because it is a higher or bigger number, it is the MAC rate that is of importance because that is what the customer experiences.
In lay terms, the PHY and MAC rate is the difference between what is promised and what is received. MoCA only quotes the MAC rate or the actual throughput–what you get. Most other standard consortiums quote the PHY rate, or theoretical data rate–what is possible but rarely probable. The package screams the product inside is big and fast, but in reality it is much slower when taken out of the box and put to work. It does not mean it is not fast. It just means it is not as fast as you would otherwise believe.
One example is the wireless data rate. Networking products based on IEEE 802.11 g., for instance, often quote a PHY rate of 54 Mpbs. How many people actually get that? The MAC rate, or real data rate, is about a fourth of that. But frankly, who cares about the real data rate? What is important is if you get Internet access from any room in the house, and did your email get to its intended destination in real time? If so, then the product did its job.
While the consumer does not care about PHYs or MACs, or theoretical vs. actual data rates, he and she do care about what is promised vs. what they get. For data and voice, lower data transfer rates are perfectly adequate. In fact, more would just be more, and more is not always better. The exceptions would be ice cream, chocolate and beer.
High definition video, however, is a completely different animal and requires high transfer rates that are reliable. Not one. Not the other. Both.
Hi def programming and content including video and gaming for instance, require very high data rates that are also reliable. The rate you get all the time. Not some of the time. Not even most of the time. All the time.
When evaluating networking equipment for your home, look closely at the performance claims and ask for proof of the real data rate that you can expect.
Insist on Truth in Networking.
Comments?
