Edge
Runs the minimum safe behavior and keeps producing timestamped events.
Fog Outage Resilience Animation
Animate local autonomy, bounded buffering, and controlled replay during fog and network outages.
animation
edge-computing
fog
resilience
architecture
interactive
Interactive fog outage resilience workbench with scenario presets, local autonomy phases, buffer sizing, overflow policy, replay ordering, sync storm risk, and mobile learning support.
Fog resilience
Outage drill
Store and forward
Keep the local mission running while the fog path is degraded.
A resilient fog design names what continues locally, what is buffered, what is reduced, and how recovery avoids turning a backlog into a sync storm.
Outage phase
Normal
Local mission
Protected
Buffer need
0.0 MB
Replay estimate
0.0 min
Current Drill
Protected
Cold Chain Warehouse
Local alarms continue while the WAN path is unavailable.
Site scope
WAN outage
Critical alarms first
Events created
0
Buffered
0
Overflow
0
Cloud gap
0 min
Outage State Machine
NormalEdge site
Fog tier
Cloud service
E
Edge controllers
Sense, act, and forward local events.
F
Fog node
Correlates local events and buffers upstream records.
C
Cloud
Receives telemetry and keeps the fleet view current.
O
Operator evidence
Health, queue depth, and replay logs prove recovery.
D
L
R
!
!
!
Local backlog
0% filled
0 min
stale
Normal operation
Edge devices send local events through the fog node and the cloud view stays current.
Buffer And Replay Budget
Within limit
Buffer sizing model
events/min x outage min x bytes/event x safety / 1048576 = required MB
This is a teaching model. Production sizing also includes protocol overhead, flash wear, retention rules, and evidence requirements.
Buffer fill
0%
Capacity is available for the expected outage window.
Critical current
0
Routine or summary
0
Replay link share
45%
Tier Responsibilities Under Stress
Low sync riskFog
Owns local correlation, queue admission, and recovery evidence.
Cloud
Receives current summaries and historical replay when the path recovers.
Learning Support
What The Animation Shows
The important motion is not only packets moving upstream. Watch the responsibility shift: the edge keeps the minimum safe behavior, the fog tier either coordinates locally or is bypassed, and the cloud becomes stale until replay finishes.
Formula And Units
Required MB = events/min x outage min x bytes/event x safety factor / 1048576. Replay time uses the selected uplink rate, a link share, and the number of stored bytes. Values are estimates for architecture comparison.
Design Trade-Offs
- Priority replay protects current alarms but delays bulk history.
- Summaries reduce storage pressure but lose raw detail.
- FIFO flooding can make recovery look fast while starving current traffic.
- Drop-oldest policies preserve recent visibility but create audit gaps.
Production Caveats
This lab does not prove resilience by itself. A real design still needs tested queue limits, replay ordering, duplicate handling, stale credential behavior, time synchronization, flash wear review, operator runbooks, and live-equivalent outage drills.