MPLS TE Application on an IP MAN

Service Overview

Carriers are converging their service bearer networks. IP/MPLS technology is essential on these converged networks because the technology allows voice, video, leased line, and data services to be transmitted on an IP/MPLS backbone network. Depending upon individual subscribers' requirements, services on a metropolitan area network (MAN) are classified into:

For individual subscribers: high-speed Internet (HSI), video on demand (VoD), and voice over IP (VoIP)
For business and enterprise subscribers: L3VPN services (business VPN) and L2VPN services (data, video, and voice services)

Table 1 lists the requirements of these services.

**Table 1** Services on an IP MAN
Service	QoS Requirements	Reliability Requirements	Security Requirements
HSI	Bandwidth guarantee: not required QoS guarantee: low	End-to-end services: Redundant links are deployed to ensure that traffic is switched to the backup link upon a primary link failure. Voice service: Traffic is rapidly switched to the backup link upon a primary link failure to ensure real-time transmission.	Services are isolated. The IP infrastructure can effectively defend against attacks and viruses, ensuring stable network operation.
VoD	Bandwidth guarantee: required QoS guarantee: medium
VoIP	Bandwidth guarantee: required QoS guarantee: high
Business VPN	Bandwidth guarantee: required QoS guarantee: medium

Networking Description

Currently, an IP MAN consists of a MAN backbone and a MAN access network, which deliver services to users. Figure 1 and Figure 2 show end-to-end service models for individual and enterprise subscribers.

Figure 1 Service model of an individual subscriber

Figure 2 Service model of an enterprise subscriber

Feature Deployment

Enterprise or individual services are core services that have bandwidth, QoS, and reliability requirements. MPLS TE tunnels are recommended as VPN tunnels on the public network to meet service requirements. For detailed deployment, see Table 2.

**Table 2** MPLS TE deployment on an IP MAN
Item	L3VPN	L2VPN
Services	Business VPN	HSI VoD VoIP
VPN tunnel on the public network	MPLS TE tunnel	MPLS TE tunnel
Reliability	Network reliability Link protection: provided using TE hot standby and BFD for CR-LSP. Node protection: provided using VPN FRR and BFD for TE tunnel. Device reliability: RSVP GR.	Network reliability Link protection: provided using TE hot standby and BFD for CR-LSP. Node protection: provided using VLL FRR and BFD for TE tunnel. Device reliability: RSVP GR.
QoS	End-to-end QoS must be configured between a user-end provider edge (UPE) and a broadband remote access server (BRAS) or service router (SR) to ensure service quality.
Security	RSVP MD5 or keychain is used for authentication.

Key deployment points are as follows: Explicit paths are configured to separately establish primary and backup CR-LSPs. The two paths do not overlap in important areas.