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Protocol Pioneers: IoT and 6LoWPAN

Kevin Ashton named a world where objects report facts without a person typing them.

Physics Phoebe is your guide for this deck.

historyprotocolpioneers

Physics Phoebe, the module guide, in a scene from this chapter.

After studying this chapter

Learning objectives

You will be able to:

Explain: Mulligan's insight -- "IoT needs IPv6, but IPv6 needs compression to fit in IoT packets" -- solved the tension between universal Internet connectivity (Cerf's vision) and resource-constrained devices (IoT reality).
Explain: RFC 2119 defines the capitalized keywords MUST, SHOULD, and MAY, so a spec can state precisely what an implementation is required to do versus what is recommended or optional.
Explain: An author publishes an Internet-Draft; a working group discusses and revises it; if it reaches rough consensus it is published as an: RFC with a permanent number.

Major section

Kevin Ashton (1968-): Coined "Internet of Things"

The central panels connect missing physical-world information to the use of tags and sensors.

This connects computer records to physical movement, explaining why sensing matters beyond the database.
He noticed a frustrating pattern: stockouts -- shelves ran out of popular products (like brown lipstick) while warehouses had plenty of inventory.

Kevin Ashton, who coined the term Internet of Things in a 1999 P&G presentation.

Major section

Kevin Ashton (1968-): Coined "Internet of Things" (continued)

Shelves could detect when stock was low and automatically reorder.

The problem: Computers knew what inventory existed in databases, but they had no idea what was on store shelves.
Humans had to manually count products and update systems.
The name signals that anything can be connected, not just traditional electronic devices.

Major section

Geoff Mulligan: 6LoWPAN Pioneer

Its placement explains how the stack carries Internet packets on constrained devices.

IPv6 headers alone are 40 bytes -- plus 8 bytes for UDP.
Mesh Routing Support 6LoWPAN enables mesh networks where devices route packets for each other, extending network range without infrastructure.

Geoff Mulligan, who led IETF standardization of 6LoWPAN for IPv6 over low-power wireless.

Major section

What Mulligan Made Possible

Battery Life: 6LoWPAN's header compression reduces packet size, saving energy on battery-powered sensors.

Matter Devices: When you buy a Matter-certified smart light or lock, it uses Thread, which runs 6LoWPAN over IEEE 802.15.4.
Mulligan's insight -- "IoT needs IPv6, but IPv6 needs compression to fit in IoT packets" -- solved the tension between universal Internet connectivity (Cerf's vision) and resource-constrained devices (IoT reality).
That compression is Mulligan's contribution.

Major section

Deep Dive: How Internet Standards Become Interoperable

A protocol travels a defined path before it becomes a standard.

The pioneers who built the Internet did more than write code.
They created a way to agree on open standards so machines from different makers could interoperate.
RFCs also standardize how requirements are written.
A proprietary protocol would offer no such guarantee across vendors.

Major section

Deep Dive: How Internet Standards Become Interoperable (continued)

That precision removes ambiguity that would otherwise break interoperability.

Most core Internet protocols are published by the: IETF (Internet Engineering Task Force) as: RFCs (Requests for Comments), documents anyone can read and implement for free.
The IETF's guiding motto, credited to David Clark, is "rough consensus and running code.": Standards are not decreed from above.
The IETF has historically wanted to see multiple independent implementations interoperate before a specification advances.

Major section

Deep Dive: How Internet Standards Become Interoperable (continued)

That culture is why the Internet, and IoT on top of it, is built from interoperable protocols rather than one vendor's proprietary system.

An author publishes an Internet-Draft; a working group discusses and revises it; if it reaches rough consensus it is published as an: RFC with a permanent number.
Foundational protocols carry famous numbers: IP is RFC 791, TCP is RFC 793, SMTP is RFC 821, and FTP is RFC 959.
Because it is an open RFC using RFC 2119 language, a sensor vendor and a cloud vendor can implement CoAP independently and still expect their products to interoperate.

Major section

Deep Dive: How Internet Standards Become Interoperable (continued)

RFC 2119 defines the capitalized keywords MUST, SHOULD, and MAY, so a spec can state precisely what an implementation is required to do versus what is recommended or optional.

The "running code" half of the motto protects against paper standards that look fine but cannot be built or do not interoperate.
A spec is only real when two teams who never coordinated can build it from the text alone and have it work.
This matters intensely for IoT, where devices from dozens of makers must coexist for a decade.
Caught at a plugfest, the spec can be clarified before publication.

Deck summary

Key takeaways

The central panels connect missing physical-world information to the use of tags and sensors.

Shelves could detect when stock was low and automatically reorder.
Its placement explains how the stack carries Internet packets on constrained devices.
Battery Life: 6LoWPAN's header compression reduces packet size, saving energy on battery-powered sensors.
A protocol travels a defined path before it becomes a standard.

Retrieval practice

Recall check 1 of 3

Physics Phoebe says: answer from memory, then check your reasoning.

Q1Vint Cerf and Bob Kahn's TCP/IP design includes the end-to-end principle: reliability logic belongs in endpoints, not in the network core. Why is this principle important for IoT?

AIt makes networks faster by reducing processing in routers

BIt allows IoT devices to work over any network type

CIt prevents hackers from intercepting IoT data in the network core

DIt reduces IoT device costs by offloading processing to the cloud

Show answer

Answer: B Correct!

Retrieval practice

Recall check 2 of 3

Physics Phoebe says: answer from memory, then check your reasoning.

Q2Andy Stanford-Clark designed MQTT with 2-byte headers (vs. HTTP's 200+ byte headers) because he was monitoring oil pipelines via satellite. How does this design choice benefit modern IoT deployments?

AMQTT is always faster than HTTP for every web and device workload

BSmall headers reduce airtime and battery use on constrained sensor links

CSmall packets are harder to intercept, so MQTT removes the need for TLS

DMQTT works only on IPv4, while HTTP requires an IPv6 network

Show answer

Answer: B Correct!

Retrieval practice

Recall check 3 of 3

Physics Phoebe says: answer from memory, then check your reasoning.

Q3Place each contribution where it changes the communication path so you can distinguish a transmission foundation from a network protocol and an application service.

AShannon: Information Theory

BMetcalfe: Ethernet

CCerf and Kahn: TCP/IP

DBerners-Lee: HTTP and the Web

EMorse: Telegraph Signalling

Show answer

Answer: A distinguish a transmission foundation from a network protocol and an application service.

Q4Complete the HTTP request demonstrating Berners-Lee's Web protocol:

Aresponse = urequests.get('http://api.example.com/sensor')

Bresponse = urequests.post('http://api.example.com/sensor')

Cresponse = urequests.send('http://api.example.com/sensor')

Dresponse = urequests.connect('http://api.example.com/sensor')

Show answer

Answer: A HTTP GET retrieves resources from a server.

Print reference

Answers

Answer key.

B · Correct!
B · Correct!
A · distinguish a transmission foundation from a network protocol and an application service.
A · HTTP GET retrieves resources from a server.