Prove each network mode isolates what it claims to isolate

applied · 85 min · Objective 4.1

Task

Test all the virtual network modes your hypervisor offers by attempting what each is supposed to prevent -- with a baseline success captured first, because a failure that was never a success proves nothing about the control.

Steps

  1. Build two guests and record their configuration in lab/netmode/guests.csv with header guest,os,adapter_mode,address.
  2. For each mode your hypervisor offers -- NAT, bridged, host-only, internal, and disconnected -- record in lab/netmode/expected.csv with header mode,reach_internet,reach_host,reach_other_guest,reachable_from_lan what you PREDICT before testing.
  3. CAPTURE A BASELINE SUCCESS in the most permissive mode available: prove each of the four reachability tests works, and record the output in lab/netmode/baseline-success.txt.
  4. Test every mode and record what actually happened in lab/netmode/actual.csv with the same header as the predictions, plus a matched column.
  5. Write lab/netmode/surprises.md for every mismatch between prediction and result, and lab/netmode/choice.csv with header requirement,mode,why for four stated requirements including 'opening something untrusted'.

Verify

awk -F, 'NR>1 && NF>=4 {n++} END {print n" guest(s)"}' lab/netmode/guests.csv
awk -F, 'NR>1 && NF>=5 {n++} END {print n" mode(s) predicted"}' lab/netmode/expected.csv
grep -c . lab/netmode/baseline-success.txt
awk -F, 'NR>1 && NF>=6 {n++} END {print n" mode(s) tested"}' lab/netmode/actual.csv
awk -F, 'NR>1 && tolower($6)!="yes" {n++} END {print n+0" mismatch(es)"}' lab/netmode/actual.csv
awk -F, 'NR>1 && NF>=3 {n++} END {print n" requirement(s) matched to a mode"}' lab/netmode/choice.csv

Two guests, three or more modes predicted and tested, a baseline success recorded BEFORE any denial, and four requirements matched. A mode where every test failed and no baseline was captured is a mode you have observed doing nothing in particular.

Notes

The requirement 'opening something untrusted' has one right answer here and it is not a network mode at all -- it is no adapter. Recording that is the point of including it.

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