Domain: Engineering — Network Engineering
Target concept: Star network

Video generation prompt: Build a star topology network on a white background, with the core switch as the central node (marked in red), and six terminal hosts as edge nodes (marked in blue). Connect the central node to all edge nodes with solid lines. Disconnect one host from the switch, and observe the communication status of the remaining nodes. Communication links are marked with green blinking lines, and the interrupted link is marked in gray.

Evaluation guide:
(i) Target concept: Fault isolation in star network topology
Minimum mechanism: A central switching node must maintain independent bidirectional data paths to each edge node; removal of one path must not alter the existence, geometry, or operational state of other paths.
(ii)Storyline: Frame 1–2: Red switch appears centered; six blue hosts appear in radial arrangement. Frame 3–4: Solid lines draw sequentially from center to each host. Frame 5: One line vanishes (or fails to draw) between switch and one host. Frame 6–10: Green blinking initiates simultaneously on the five intact lines; gray (or blank) state persists on the interrupted link. Perspective: Fixed front-facing orthographic view; no camera movement; all elements fully visible within frame at all times.

Manual:
Experimental Procedure
1. Place one red switch at center of white background.
2. Place six blue hosts evenly around it.
3. Draw solid lines connecting center switch to all six hosts.
4. Remove (or omit) the line to one host.
5. Animate green blinking on the five remaining lines; render the interrupted link as gray (or absent).
Observation of Experimental Phenomena
- Six blue hosts and one red central switch visible.
- Five green blinking lines connect switch to five hosts.
- One host has no green line and its connection is gray (or missing).
- All other hosts maintain green blinking links.
Summary of Experimental Principles
Star topology isolates failures: disconnecting one host affects only that host; all others retain full connectivity to the core switch.

Prompt Grounding rubric:
level_1: No star-shaped arrangement is shown; no red central switch node and no blue host nodes appear; no solid connecting lines are drawn; there is no moment where a host becomes disconnected from the switch.
level_2: A red central node or blue host nodes appear, but at least two of the following are wrong: there are not six blue hosts, the lines don't all originate from the single shared center, the hosts aren't shown connected to the switch before any disconnection, or no host is ever shown losing its connection.
level_3: A red switch sits at the center with six blue hosts arranged around it; solid lines connect the switch to all six hosts before anything changes; afterward, exactly one of the six connecting lines is removed (that host now has no line to the switch) while the other five lines remain drawn.
level_4: Everything at the 3-point level is present, and in addition, the disconnected host is unambiguous: it is the only one of the six with no solid line reaching the switch; all six hosts are individually visible and spaced apart with no overlap; no extra nodes, stray lines, or off-palette colors appear anywhere in the frame.
level_5: Everything at the 4-point level is present, and in addition, the switch and all six hosts are rendered as clean, evenly sized shapes with clear, non-overlapping edges; each of the six lines is drawn fully visible from end to end (no line cut off at the frame border); the disconnected host's missing line leaves a visibly clean gap rather than a stray line fragment; no node or line is duplicated or mislabeled anywhere in the sequence.

Scientific and Causal Correctness rubric:
level_1: The video gives no indication of which links are carrying communication after the disconnection (no blinking, no color difference between links), so there is no visible correspondence between the broken connection and a change in communication state.
level_2: Some links are colored green or gray, but the assignment is backwards or inconsistent with fault isolation: e.g., the disconnected host's link blinks green, a still-connected host's link is shown gray, or the blinking pattern fails to distinguish the broken link from the working ones.
level_3: After the disconnection, green blinking appears on exactly the five links that still reach the switch, and the sixth (disconnected) link is shown gray or absent, matching how a star topology isolates a single link failure without affecting any other host's connectivity.
level_4: Everything at the 3-point level is present, and in addition, all five green links blink in sync with each other (turning on and off together, not staggered); the blinking stays confined to the links themselves and never appears on the switch, the hosts, or the background.
level_5: Everything at the 4-point level is present, and in addition, the five green links keep blinking at the same steady rate for as long as the video runs; the gray link stays a fixed, solid, non-blinking gray for the rest of the video; no link ever shows an in-between state (partially green, fading, or flickering) that would blur the distinction between connected and disconnected.

Spatiotemporal Consistency rubric:
level_1: A node or a connecting line suddenly appears in a different spot with no motion shown getting it there; a host or the switch blinks fully in and out of existence with no fade or transition; a line appears or vanishes instantly with no drawing animation; the white background changes color or texture partway through.
level_2: A node or line changes size or rotates abruptly; a line is drawn with a visible gap or an inconsistent stroke partway through (e.g., it turns dashed mid-draw); the scene's lighting or shading shifts noticeably between one moment and the next with nothing on screen to explain why.
level_3: The switch and all six hosts stay in the same place relative to the white background throughout; each of the six lines is drawn smoothly from the switch outward with no jump or gap; the disconnection is shown by one line simply not being drawn (or being cleanly removed) without shifting any node's or line's position; nothing bends, tears, or breaks apart unexpectedly.
level_4: Everything at the 3-point level is present, and in addition, the line-drawing animation finishes completely before any blinking starts; the five green links begin blinking at the same moment, only after the whole topology has settled into its final layout; there is no visible stutter or repeated frame during the drawing or blinking.
level_5: Everything at the 4-point level is present, and in addition, the six hosts stay arranged in a visually even, radially symmetric pattern around the switch for the whole video; the spacing between the switch and each host looks consistent from one host to the next; the viewpoint never zooms, pans, or tilts; the drawing and blinking motions keep a steady, even pace from start to finish rather than suddenly speeding up or slowing down.