Implementing QoS in a nation-wide Service Provider MPLS Core Network: A case study
Lei Wang Telenor Networks
During the past couple of years Service Providers worldwide have experienced a press for cost reduction while the traffic volume in the network continues to increase. Major bandwidth driven applications are peer-to-peer protocols which are not revenue bringing. Many of the service providers have also implemented IP/VPN services utilizing the same core infrastructure. To be able to scale the network optimally and offer network redundancy only for selected premier services, one has to enable QoS in core network. This presentation is a case study and lessons learned from enabling QoS on Telenor's multi-service MPLS core network. Telenor is the major service provider in Norway. It is among the first service providers worldwide deploying a pure IP/MPLS core infrastructure (built 1999) and offering MPLS/VPN services as well as broadband Internet access upon it. It was not before we started the implementation of QoS in MPLS core before we realized that we were early on this again - in terms of feature implementations from both our vendors: Juniper and Cisco. We would like to take the opportunity in MPLS2004 to address the major challenges encountered and share our lessons learned. In this presentation we would go through the following areas:
- A quick overview on traffic picture as a whole for core networks: what do end-users use Internet for - changes and trends.
- QoS design on Telenor's MPLS core in depth: Marking and Queuing scheme
- Challenges encountered:
Marking for InterAS and MultiVPN customers
Making a clean cut between core QoS domain and edge QoS domain
Accounting information and MiBs
The correct prioritization of router originated traffic - Routing protocols, SNMP, Netflow etc.
Compatibility challenges between vendors.
- Lessons learned
The importance of having a clean cut between Core and Edge QoS domains
Which building blocks do we need from the vendors in order to build this boundary? Among others the needs for flexible EXP setting in MPLS label stack.
The importance of NMS integration and scaling tools for network planning