Mike, Re: Re-routing, or detouring, of Internet-bound traffic away from the normal voice PSTN, versus the splitter action in DSL techs, you ask:
>>Sounds a lot like the "splitter" we talked about earlier. What does this initiative do that the splitter won't? <<
True, it may sound like there is a great similarity, and there actually is, in a fundamental way.
But the splitting action in DSL is facilitated by a "physical" layer divergence of two content-bearing channels, voice and data, through a frequency selective process.
VOICE: The lower frequencies associated with voice are passed one way (to the telephone instrument) on the customer premises side, and to the telco switch on the central office side.
DATA: The higher frequencies associated with data are passed to the DSL modem element, and then to the data terminal equipment (the PC, e.g.) on the customer side, and to the routed ISP network on the central office side.
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Whereas, the re-routing of Internet-bound traffic at the central office switch in order to alleviate congestion takes place at a higher, logical level using auto-sensing of traffic type, and "routing" of same, determined by logical addresses in the packet headers. The bypass route is determined using Layer 3 routing protocols.
More recently, there have been other schemes introduced that shunt Internet-bound traffic via a separate ATM overlay network to designated ISP POPs, under the supervision of SS7 end-point controls.
Here, too, the distinction is made at a logical level, not at a physical one. In this instance, Layer 3 packets are mapped onto Layer 2 ATM cells for delivery to the remotely located ISP, where they are unpacked again into their native Layer 3 format for shipment over the Internet.
HTH, Frank C.
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