The most likely reason an insurance brokerage would enforce VPN usage is to encrypt sensitive data in transit. A VPN (Virtual Private Network) is a technology that creates a secure and encrypted tunnel between two or more devices over a public network, such as the internet. A VPN allows users to access remote resources or services as if they were on the same private network, while protecting their data from interception, modification, or spoofing by malicious actors. An insurance brokerage would use a VPN to protect the confidentiality and integrity of sensitive data, such as customer information, financial records, or insurance policies, that are transmitted over the internet. Reference: CompTIA Network+ N10-008 Certification Study Guide, page 403; The Official CompTIA Network+ Student Guide (Exam N10-008), page 15-5.

CRC stands for Cyclic Redundancy Check, and it is a type of error-detecting code used to detect accidental changes to raw data. If the CRC count is increasing on a particular interface, it indicates that there might be an issue with the cabling, which is causing data corruption. Reference:
Network+ N10-008 Objectives: 2.1 Given a scenario, troubleshoot common physical connectivity issues.

North-south traffic is any communication between components of a data center and another system, which is physically out of the boundary of the data center. It is also referred to as client-server traffic, as it usually involves requests from end users or external applications to the data center resources. For example, when a user accesses a web application hosted in a data center, the traffic between the user's browser and the web server is considered north-south traffic.

Multimode fiber optic cables use multiple paths of light that bounce off the cladding, which is a layer of glass or plastic that surrounds the core of the cable.
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Site-to-site VPN provides the best security for connecting a new datacenter to an old one because it creates a secure tunnel between the two locations, protecting data in transit. Reference: CompTIA Network+ Certification Study Guide, Chapter 5: Network Security.