The MPLS WG Archive

["HANSEN CHAN" <hansen.chan@alcatel.com>]

> But as I understand it, the added value from IP VPNs either comes from
> security (whether this is "isolational" in nature like an ATM or Frame
> Relay VPN, or "truly secure" as in the case of an ecrypted ATM or IPSec VPN
> is up to the user), or from "perceived service enhancement".  The latter
> could be via a CoS mechanism, which MPLS can potentially offer, or from a
> hard QoS mechanism which can only be offered from...
>
> a: A TDM mechanism (like SONET/SDH, which is expensive).
> b: A native ATM service.
> c: An over-provisioned stat mux service (eg. IP), which is also expensive
> in the long term.

Geoff,

I agree with your points above. However, I don't think there is anything stop MPLS implemented with a hard QoS mechanism like ATM
has done. A good LSR with the necessary traffic management infrastructure (queuing and scheduling) can achieve the same level, if
not better QoS.

Cheers,
Hansen