Traffic Engineering (TE) in transport networks, particularly using technologies like MPLS-TE, provides several key benefits. Its primary function is to optimize the utilization of network resources by steering traffic along paths that may not be the default shortest path chosen by an IGP. This explicit path control, or traffic steering (C), prevents congestion on certain links while others are underutilized, leading to better utilization of network capacity (B). Furthermore, TE significantly enhances resiliency (D) by enabling mechanisms like Fast Reroute (FRR), which pre-establishes backup paths to provide sub-50ms restoration in the event of a link or node failure, ensuring high service availability.

A. Scaling access points is related to the design and expansion of the radio or user access layer, not a direct function or benefit of traffic engineering within the transport network core.

1. Official Vendor Documentation: Nokia, SR OS R19.10.R1 MPLS Configuration Guide, Part Number: 3HE 15680 AAAD TQZZA, Edition 01.

Section: Traffic Engineering Overview: "The main goal of MPLS traffic engineering is to enable constraint-based routing of label switched paths (LSPs) across a network... This allows the network operator to route traffic in order to avoid congestion and make the best use of available bandwidth." (Supports B and C).

Section: MPLS Fast Reroute (FRR): "MPLS Fast Reroute (FRR) provides for the fast rerouting of traffic in the event of a link or node failure in an MPLS network... FRR provides link and node protection for LSPs." (Supports D).

2. Peer-reviewed Academic Publications: Awduche, D., et al. "RSVP-TE: Extensions to RSVP for LSP Tunnels." RFC 3209, December 2001.

Section 1. Introduction: "A primary goal of traffic engineering is to facilitate efficient and reliable network operations... This is accomplished by moving traffic from congested parts of a network to less congested parts." (Supports B and C). The document also discusses establishing backup tunnels for "enhanced resilience." (Supports D).

3. University Courseware: Stanford University, CS 244: Advanced Topics in Networking, Lecture Notes on "Traffic Engineering".

The course materials typically outline the two primary goals of TE as 1) Performance Optimization (improving resource utilization, avoiding congestion) and 2) Resilience (fast recovery from failures). This directly corresponds to options B, C, and D. Traffic steering is the mechanism to achieve optimization.