Exercise 3: What's Missing From "I Now Fully Understand How Every Request Works" — Possible Solution
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What's missing:

Per this chapter's own warn-box, at least four real gaps remain even
after completing the full six-step journey:

1. Dynamic routing protocol internals. "This course deliberately never
went deep on dynamic routing protocols themselves -- BGP/OSPF/RIP were
named (net1-6) but never taught in depth." Step 2's own routing
explanation names BGP as the mechanism coordinating internet-scale
routing but never explains how BGP itself actually decides paths,
handles failures, or negotiates between different networks' own
routing policies.

2. CDN and load-balancing behavior. "Real-world CDN and load-balancing
behavior (DNS or anycast routing returning different answers depending
on the requester's own location) is a genuine simplification
acknowledged here, not covered." This chapter's own Step 1 walks
through a single, simple DNS resolution returning one fixed IP address
-- but many real, large-scale websites use DNS or anycast techniques
that deliberately return DIFFERENT answers to different requesters
based on their location, load balancing, or other factors entirely
unaddressed by this capstone's own simplified walkthrough.

3. IPv6-specific behavior. "IPv6-specific resolution and routing
differences were only given a first look (net1-4) -- this entire
capstone traces the IPv4 case for simplicity." Every step in this
chapter's own journey specifically used an IPv4 example address
(203.0.113.10); the resolution and routing mechanics for an AAAA-based
IPv6 request, while conceptually similar, were never traced through in
the same level of detail this capstone gave to IPv4.

4. HTTP itself. "HTTP itself -- headers, caching, methods -- was
deliberately left uncovered, arguably web-development territory the
site already addresses elsewhere." Step 5 names that an HTTP GET
request gets sent and a response comes back, but never explains what's
actually inside that request or response beyond the fact that it
travels reliably over the already-established connection.

Why the reader's conclusion overstates the result:

This capstone successfully traces the core mechanical journey of a
single, typical HTTPS request through DNS, routing, the TCP handshake,
TLS, and the HTTP exchange -- a genuine and valuable foundation. But
"every website request on the internet" is a much broader claim than
what was actually covered, since real-world requests routinely involve
CDN/anycast complexity, IPv6, and internet-scale dynamic routing that
this course's own warn-box explicitly named as left out, not covered
implicitly.

WHY THIS WORKS AS AN ANSWER
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This lists all four specific gaps the chapter's own warn-box names,
rather than picking just one, and distinguishes what the capstone
genuinely does establish (the core mechanical journey for a typical
request) from the much broader claim the reader's conclusion makes.