Dan M. MacNeil wrote:
"Unlike DSL a T1 is tariffed and regulated so
guaranteed a particular level of quality."
Most T1 contracts provide for a certain level of performance at layer 1 (>99.97% error-free seconds, etc.) and a certain level of responsiveness when trouble tickets are opened. For these instances, the remote hardware is a significant piece of the testing and resolution process, as the SmartJack can be looped back to the CO for testing purposes.
Most DSL services change format one or more times in the middle of the span, i.e. go from DSL to ATM at the DSLAM, and may transit several ATM switches on the path to the serving router. This limits the testing points and therefore the performance guarantees possible, and increases the finger pointing.
"DSL has high latency"
Not necessarily, but the asymmetric and shared nature means packets can be buffered or dropped at lots of layer 1/2 places between layer 3 nodes, potentially degrading performance.
Theoretically (3) fast DSL connections would give us more bandwidth and redundancy than one $400 T1 (we get non profit pricing)
Redundancy? Ha. It's all going to ride the same network, so backhoe fade will always hit you hard.
Operationally, if I ran a DSL access network, I wouldn't offer BGP over DSL, period, and I would think many other networks would do the same. Three high-speed DSL connections for <$400 would (for once) not actually get the attention of senior management such that they'd try to override me either.
pt