Course audit report

Fundamentals of Communications and Networks

Done Role: Network Engineer 5 Findings Computer Networks — Tcp/ip Layered Protocol Stack
Auditor Done Market Fit Done Topics Done
Run another role
5 findings · 1 high 3 medium 1 low
Security risk Week 15 - VPNs.pptx slide 5

What the slide says

Most common VPN communications protocol standards: Point-to-Point Tunneling Protocol (PPTP) for individual client to server connections; Layer 2 Tunneling Protocol (L2TP) for individual client to server connections

Primary source ✓ Source checked

learn.microsoft.com ↗

Beginning with Windows Server 2025, new RRAS setups don't accept VPN connections based on PPTP and L2TP protocols.

What to learn instead

Do not present PPTP and L2TP as 'most common' VPN standards. Microsoft formally deprecated both in Windows Server and explicitly recommends against their use 'due to their lack of security features'. Teach IKEv2/IPsec, OpenVPN, WireGuard, and SSTP instead; if PPTP/L2TP are mentioned, frame them as legacy/insecure for historical context only (PPTP's MS-CHAPv2 has been broken since 2012).

Incorrect Week 12 _13 _ 14 - Application Layer.pptx slide 14

What the slide says

HTTP 1.1 [RFC 7320]

Primary source ✓ Source checked

www.rfc-editor.org ↗

URI Design and Ownership

What to learn instead

RFC 7320 is titled 'URI Design and Ownership' and has nothing to do with HTTP/1.1. The HTTP/1.1 messaging spec is currently RFC 9112 (which obsoletes RFC 7230); HTTP semantics are in RFC 9110. Update the citation to RFC 9110/9112 (or, if older material is desired, RFC 7230).

No longer works Week 12 _13 _ 14 - Application Layer.pptx slide 16

What the slide says

object can be HTML file, JPEG image, Java applet, audio file,…

Primary source ✓ Source checked

docs.oracle.com ↗

The Applet API is deprecated, no replacement.

What to learn instead

Remove 'Java applet' from the list of web-page object types. The Applet API was deprecated in JDK 9 (JEP 289), deprecated for removal in JDK 17 (JEP 398), and all major browsers have removed support for the NPAPI Java plug-in. Use HTML5/JavaScript/WebAssembly instead.

Outdated Week 15 - VPNs.pptx slide 5

What the slide says

IPsec is built into IPv6 standard and is implemented as an add-on to IPv4

Primary source ✓ Source checked

www.rfc-editor.org ↗

Previously, IPv6 mandated implementation of IPsec and recommended the key management approach of IKE. This document updates that recommendation by making support of the IPsec Architecture [RFC4301] a SHOULD for all IPv6 nodes.

What to learn instead

Update the slide to reflect that IPv6 no longer mandates IPsec. RFC 6434 (Dec 2011), and its successor RFC 8504, downgraded IPsec from MUST to SHOULD for IPv6 nodes. IPsec is available for both IPv4 and IPv6 but is not a built-in mandatory part of IPv6 in current standards.

Outdated Week 12 _13 _ 14 - Application Layer.pptx slide 42

What the slide says

RFC 2822 defines syntax for e-mail message itself

Primary source ✓ Source checked

www.rfc-editor.org ↗

Obsoletes: 2822

What to learn instead

Cite RFC 5322 (Internet Message Format, October 2008), which obsoletes RFC 2822. RFC 5322 has itself been updated by RFC 6854.

Course is a TCP/IP networking-fundamentals survey; every high-frequency DevOps/SRE demand (Docker, Kubernetes, Terraform, CI/CD, Prometheus/Grafana/Datadog, AWS, Linux, Bash, Git, Go, on-call/SLOs) is cross-domain to networking with zero partial coverage to extend, so no in-scope gaps can be surfaced under the extend-only and depth-bound rules.

No extendable gaps for this role

Stale only flags gaps that the course already partially covers. It won't push you toward Kubernetes when you're sitting in a Unicode course. For devops_sre, every high-frequency market demand is in a different area from what this course actually teaches.

Try a different target role on the run page, or run Stale on a course whose subject area overlaps the role you're aiming for.

What the curriculum actually teaches (25 skills)
  • TCP protocol mechanics (3-way handshake, sequence/ACK numbers, retransmission, fast retransmit) · Week 10 _ 11 - Transport Layer
    Slide 42: 'TCP 3-way handshake ... clientSocket.connect((serverName,serverPort))'; Slide 34: 'TCP fast retransmit ... arrival of three duplicate ACK causes the sender to retransmit its oldest unACKed segment'
  • TCP congestion control (AIMD, slow start, Tahoe/Reno, BBR, ECN) · Week 10 _ 11 - Transport Layer
    Slide 50: 'Cut in half on loss detected by triple duplicate ACK (TCP Reno) ... Cut to 1 MSS ... when loss detected by timeout (TCP Tahoe)'; Slide 59: 'BBR deployed on Google's (internal) backbone network'; Slide 60: 'Explicit congestion notification (ECN)'
  • TCP flow control (rwnd, receive buffer) · Week 10 _ 11 - Transport Layer
    Slide 39: 'TCP receiver advertises free buffer space in rwnd field in TCP header ... RcvBuffer size set via socket options (typical default is 4096 bytes)'
  • UDP (connectionless, header format, use cases: DNS/SNMP/HTTP/3) · Week 10 _ 11 - Transport Layer
    Slide 11: 'UDP use: streaming multimedia apps ... DNS, SNMP, HTTP/3'; Slide 16: 'UDP segment header ... source port # ... checksum'
  • HTTP/1.1 (persistent vs non-persistent, methods, status codes, conditional GET, web caches/proxies) · Week 12 _13 _ 14 - Application Layer
    Slide 23: 'Persistent HTTP (HTTP1.1): server leaves connection open after sending response'; Slide 26: 'POST method ... GET method ... HEAD method ... PUT method'; Slide 28: '200 OK ... 301 Moved Permanently ... 404 Not Found'; Slide 29: 'A Web cache—also called a proxy server'
  • DNS (hierarchical name servers, root/.com/.edu, hostname-to-IP resolution, DNSSEC) · Week 12 _13 _ 14 - Application Layer
    Slide 48: 'client queries root server to find .com DNS server ... client queries .com DNS server to get amazon.com DNS server'; Slide 50: 'DNSSEC – provides security (authentication, message integrity)'
  • Email protocols (SMTP RFC 5321, IMAP RFC 3501) · Week 12 _13 _ 14 - Application Layer
    Slide 38: 'SMTP RFC (5321) uses TCP to reliably transfer email message from client ... to server, port 25'; Slide 43: 'IMAP: Internet Mail Access Protocol [RFC 3501]'
  • FTP (control/data connections, port 21/20, ASCII commands) · Week 12 _13 _ 14 - Application Layer
    Slide 34: 'FTP client contacts FTP server at port 21 ... server opens 2nd TCP connection (for file) to client ... TCP data connection port 20'
  • P2P / BitTorrent (chunks, tracker, tit-for-tat) · Week 12 _13 _ 14 - Application Layer
    Slide 53: 'P2P file distribution: BitTorrent ... file divided into 256Kb chunks ... tracker: tracks peers'
  • Video streaming concepts (CDNs, jitter buffer, playout) · Week 12 _13 _ 14 - Application Layer
    Slide 61: 'continuous playout constraint ... but network delays are variable (jitter), so will need client-side buffer'
  • IP datagram, IPv4 32-bit addressing, dotted-decimal notation · Week 8 _ 9 - Network Layer
    Slide 26: 'IP address: 32-bit identifier associated with each host or router interface ... dotted-decimal IP address notation'
  • CIDR / subnetting / longest prefix matching · Week 8 _ 9 - Network Layer
    Slide 32: 'CIDR: Classless InterDomain Routing ... address format: a.b.c.d/x'; Slide 15: 'Longest prefix matching ... use longest address prefix that matches destination address'
  • NAT (private address space, port translation, NAT table) · Week 8 _ 9 - Network Layer
    Slide 40: 'private IP address space (10/8, 172.16/12, 192.168/16 prefixes)'; Slide 41: 'replace (source IP address, port #) ... with (NAT IP address, new port #)'
  • IPv6 (128-bit addresses, transition tunneling) · Week 8 _ 9 - Network Layer
    Slide 44: 'IPv6 increases the size of the IP address from 32 to 128 bits'; Slide 47: 'tunneling: IPv6 datagram carried as payload in IPv4 datagram'
  • Router data plane vs control plane (incl. SDN concept) · Week 8 _ 9 - Network Layer
    Slide 5: 'two control-plane approaches: traditional routing algorithms ... software-defined networking (SDN): implemented in (remote) servers'
  • Ethernet (frame structure, MAC addresses, CSMA/CD with binary backoff) · Week 6 _ 7 - Link Layer and LANs
    Slide 28: 'Ethernet CSMA/CD algorithm ... after mth collision, chooses K at random from {0,1,2, …, 2m-1}'; Slide 51: 'addresses: 6 byte source, destination MAC addresses'
  • ARP (IP→MAC resolution, ARP table, broadcast FF-FF-FF-FF-FF-FF) · Week 6 _ 7 - Link Layer and LANs
    Slide 38: 'B's MAC address not in A's ARP table, so A uses ARP to find B's MAC address ... Ethernet frame (sent to FF-FF-FF-FF-FF-FF)'
  • Multiple access protocols (TDMA, FDMA, CSMA/CD, CSMA/CA, polling, token passing) · Week 6 _ 7 - Link Layer and LANs
    Slide 32: 'CSMA/CD used in Ethernet ... CSMA/CA used in 802.11 ... taking turns: polling from central site, token passing'
  • Error detection (parity, Internet checksum, CRC) · Week 6 _ 7 - Link Layer and LANs
    Slide 15: 'Cyclic Redundancy Check (CRC) ... can detect all burst errors less than r+1 bits ... widely used in practice (Ethernet, 802.11 WiFi)'
  • Physical-layer signals (analog/digital, sine waves, bandwidth in Hz) · Week 4 _ 5 - Physical Layer wired and wireless connectivity
    Slide 25: 'The range of frequencies contained in a composite signal is its bandwidth'; Slide 30: '1 can be encoded as a positive voltage and a 0 as zero voltage'
  • Signal impairment (attenuation, distortion, thermal/induced/crosstalk/impulse noise) · Week 4 _ 5 - Physical Layer wired and wireless connectivity
    Slide 41: 'Attenuation ... is the loss of energy'; Slide 44: 'Thermal noise ... Induced noise ... Crosstalk ... Impulse noise'
  • Network performance metrics (bandwidth in bps, throughput, latency components, jitter) · Week 4 _ 5 - Physical Layer wired and wireless connectivity, Week 1 - Introduction to Data Communication
    Slide 52 (Wk 4/5): 'Latency is made of four components: propagation time, transmission time, queuing time, processing delay'; Slide 57 (Wk 4/5): 'Jitter is a problem if different packets of data encounter different delays'
  • Network types and topologies (LAN/WAN/MAN/PAN; mesh/star/bus/ring) · Week 1 - Introduction to Data Communication
    Slide 19: 'Personal Area Network (1-10m) ... Local Area Network ... Metropolitan Area Network ... Wide Area Network'; Slides 14–17 cover Mesh/Star/Bus/Ring
  • VPNs (IPsec, SSL, MPLS, PPTP, L2TP, tunneling) · Week 15 - VPNs
    Slide 3: 'VPN uses virtual connections based on IPsec/SSL ... Most network providers also offer private VPNs based on MPLS'; Slide 5: 'PPTP ... L2TP ... IPsec for network-to-network connectivity'
  • SNMP (mentioned as a UDP-based application) · Week 10 _ 11 - Transport Layer
    Slide 11: 'UDP use: ... SNMP'; Slides 13–15 use 'SNMP server / SNMP client' as the running example for UDP transport-layer actions

No prescriptions are issued. The Market-fit agent surfaced zero in-scope gaps (gaps: []). The course is an undergraduate TCP/IP networking-fundamentals survey, and every high-frequency DevOps/SRE demand in the postings — Docker (100%, post_061–post_072), Bash (100%, post_061–post_072), Python (92%), Git (92%), Linux/Kubernetes/Monitoring (83%), Terraform/CI-CD/AWS (75%), Prometheus/GitHub Actions/On-call/Go (67%), Helm/Datadog (58%), Jenkins/Grafana/SLOs/Ansible (50%), GitLab CI/ArgoCD/Vault/Incident Response (42%) — is a cross-domain tooling/operations skill with no partial coverage in any of the seven course weeks to extend. Under Rule 1 (extend-only) and Rule 2 (respect the conceptual depth bound of a top-down networking survey), none of these tools can be honestly grafted onto Weeks 1, 4/5, 6/7, 8/9, 10/11, 12/13/14, or 15 without inventing a wholly new topic or pushing the course past its stated depth.

These zero prescriptions close 0% of the DevOps/SRE market gap from within this course's scope — which is the correct answer, not a failure of the analysis. The course is doing its job (teaching the TCP/IP stack); the DevOps/SRE skills the market wants belong in separate courses on Linux systems administration, containers/orchestration, infrastructure-as-code, CI/CD, and SRE practice. Recommending that this networking course bolt on Docker, Kubernetes, Terraform, or Prometheus would violate the extend-only rule, the depth bound, and the course's pedagogical intent. The honest curricular recommendation is upstream of Topics: add dedicated DevOps/SRE coursework to the program, and keep this course focused on protocol mechanics. Note also that the Auditor's flagged VPN content (PPTP/L2TP as 'most common', IPsec mandatory in IPv6, RFC 7320/2822 citations, Java applets) should be corrected per the suggested replacements — but those are correctness fixes, not market-driven prescriptions, so they do not appear here.