Hello,
I can think of several reasons to "jump" to MPLS.
1) Cost
MPLS offers several advantages to the SP (!) in allowing to transport all sort of services across one single backbone. Thus the resource utilization and operational expenses might be lowered for the SP and it can be cheaper to offer MPLS ...
2) Cost (ok, just kidding)
2) any-to-any connectivity
Especially with VoIP any-to-any connectivity is giving lowest possible delay times. With a FR hub-and-spoke design you get large(r) delay when spoke to spoke calls are required.
3) QoS
A FR switch does not "know" which traffic is important and which traffic is not. Thus VoIP priorization is somewhat difficult to achieve. The resulting requirement in a FR network also utilized for VoIP (or any other critical traffic) should not burst above CIR.
In an MPLS network the same classification and traffic treatment can be applied as within an IP network (mapping IP Precedence to MPLS exp bits).
4) Variety of connection options
ethernet, ppp, FR, ATM, IPSec ... there are many options to connect to an MPLS VPN. It is thus much more likely to have something at hand matching the customer requirements.
5) Easier setup of Central Service, overlapping VPN
The customer connectivity requirements are matched in a more flexible way through MPLS VPNs than with FR. In the latter you need additional firewalls to sort out extranet, remote access and central service VPNs.
Hope this helps! Please rate all posts.
Regards, Martin
