Traffic optimization vs. network transparency

Over the years, we’ve had a gradual loss of transparency in the telecommunications environment.  By “transparency,” we mean bit-for-bit replication of traffic from point A to point B, with no changes to the bit stream.

The transparency loss has come about by the advent of packet-switching technologies. Packet switching saves most of us a ton of money on network bandwidth. But technologies that alter bit streams in transit require network operators to more closely monitor and manage their networks.

At one time, the majority of corporate telecommunications was based on dedicated bandwidth services. When multiple applications shared these services, TDM partitioned them from one another.  The network never touched the content of the data.  Bits came into the network at one location and they were reproduced at the other end without any intermediate processing. So it was pretty easy to tell how an application was performing.

There was never a question as to whether the fundamental nature of the communications was changed by the network.  In the dedicated-circuit model, the network was just too dumb to make any changes.

With the advent frame relay, ATM and IP services, which improved upon X.25 packet-switching concepts, we started futzing around with the fundamental content in transit.  The beauty of packet switching is that more traffic can be pushed through the network. But because the switches and the network are “content-aware,” transparency is lost.

Today, we’re moving to an entirely new level of futzing with the data stream.  Many of today’s most exciting technologies – compression, traffic shaping and firewalls, for example – interact with the content of the traffic.  The good news about these technologies and products is that they allow for much more efficient use of network resources.

At the same time, there’s a requisite level of responsibility that accompanies the use of them.  Namely, you must understand exactly what the technology is doing to your traffic and how it is affecting the fundamental nature of the traffic flows.

Overall, there’s no question that the products mentioned represent positive developments – just like frame relay was a great advancement over private lines for many organizations.  But you still need to be aware that there’s no free lunch. You’ll have to continue to balance the management trade-offs that accompany enhanced data manipulation.