When traffic moves laterally between VMs within the same network or subnet, it is known as east-west traffic. This contrasts with north-south traffic, which refers to communication between internal and external networks.

Breakdown of Options:

A. East-west – Correct answer. This refers to traffic between internal servers or VMs, which is a common security concern.

B. Point-to-point – Point-to-point describes a direct connection between two devices, but does not specifically define lateral movement.

C. Horizontal-scaling – This refers to adding more instances or nodes in cloud computing, unrelated to traffic flow.

D. Hub-and-spoke – This network topology describes a centralized design, not lateral traffic.