The document discusses decentralization trends in computing and argues against fully decentralizing the internet with permissionless blockchains. It provides historical context on peer-to-peer networks and their problems with free riding and instability. While blockchains created enthusiasm for applications like cryptocurrencies, the document outlines issues with permissionless blockchains like performance limitations and security fragility. It advocates for edge-centric computing with permissioned blockchains that are disentangled from cryptocurrencies to address scalability while spreading trust and control between participants rather than relying on central entities.

1. Please, do not decentralize
the Internet with
(permissionless) blockchains
Pedro García López, Alberto Montresor,
Anwitaman Datta

2. Table of Contents
• Motivation
• History of P2P Networks
• Blockchain hype and problems
• Edge-centric computing and permissioned
blockchains
• Conclusions
2

3. MOTIVATION

4. Edge-centric Computing:
Vision and Challenges
4
IEE P2P Steering Committee
“In many aspects of human activity, there has
been a continuous struggle between the forces of
centralization and decentralization. Computing
exhibits the same phenomenon; we have gone
from mainframes to PCs and local networks in
the past, and over the last decade we have seen a
centralization and consolidation of services and
applications in data centers and clouds.”

5. HISTORY OF P2P
NETWORKS

6. P2P origins
6

7. Distributed Hash Tables
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8. Distributed Hash Tables
• Open Services [OpenDHT]
• File sharing [CFS, OceanStore, PAST]
• Web cache [Squirrel, Coral]
• Censor-resistant stores [Eternity, FreeNet]
• Application-layer multicast [Narada, Scribe]
• Event notification [Scribe]
• Streaming [SplitStream]
• Naming systems [ChordDNS, INS]
• Query and indexing [Kademlia]
• Communication primitives [I3]
• Backup store [HiveNet]
• Web archive [Herodotus]

9. P2P euphoria
• Diaspora
• FreedomBox
• Yacy Search engine
• ArkOS
• IPFS
• BitTorrent
• Wuala
• Spotify
• Skype

10. P2P decline

11. Problems of Open P2P
Networks
• Free riding and incentives
• Performance problems due to instability,
heterogeneity and churn
• Security and fragility of open networks
and peers
• System Complexity and maintenance
11
Economical Rice Podcast

12. BLOCKCHAIN HYPE
AND PROBLEMS

13. Blockchain basics
13
Lexology.com

14. Cryptocurrencies
14

15. Blockchain euphoria
• Initial Coin Offering (ICO)
●
> 1000 (2018)
●
Ethereum raised $18m in 2014
●
Block.one raised $4bn for the EOS blockchain
●
Telegram raised $1.7bn for their cryptocurrency
●
Tron bought the BitTorrent company for $140m
●
FileCoin’s ICO received $200m million from accredited investors
• Decentralized apps
●
DTube (Decentralized Youtube)
●
Graphite Docs (decentralized Google Docs)
●
Hearth (decentralized Dropbox and Web
hosting service)
●
Props (decentralized video streaming)
●
FileCoin (decentralized storage)
●
OpenBazaar (decentralized eBay)
15

16. Problems of Permissionless
Blockchain Networks
• Incentives
●
People are no longer mining Bitcoin on their home laptops
●
The increasing resources required from participant nodes is
expelling normal users
• Performance
●
Off-chain protocols, trusted groups, centralization, ...
• Security and fragility
●
Attacks: DAO, Ethereum Classic, Dapps and EVMs
• System Complexity and maintenance
●
Solidity, code complexity and size, updates
16

17. Problems of Permissionless
Blockchain Networks
• They cannot become a universal substrate
for a decentralized Internet
• Volatile cryptocurrencies cannot compete
with Cloud stable pricing
• Scalable services require disaggregation
compute/storage, content distribution
networks, and partitioned shared-nothing
services
17

18. Disparate communities
18

19. EDGE-CENTRIC
COMPUTING AND
PERMISSIONED
BLOCKCHAINS

20. Edge-centric computing v2
20
The constant struggle between the forces of
centralization and decentralization is inherent
to the human nature and history. In the end,
there is always a competition for power
involving control and trust.
In a centralized system, the participants must
trust a central entity, which can effectively
exercise control over them. In a decentralized
system, both trust and control are spread
between the participants.

21. Edge-centric Computing:
Vision and Challenges
21

22. Edge-centric Computing v2
22

23. Permissioned Blockchains
• Authenticated servers and controlled networks
• Crash fault-tolerant (CFT) and byzantine fault
tolerant (BFT) consensus protocols
• Disentangled from Cryptocurrencies
• Support for Smart contracts, decentralized Identity
• Blockchain as a Service
23

24. Challenges
• Hybrid architectures
●
DPKI ? Solid ?
• Blockchain islands
• Interoperability
●
Decentralized Identity
• Control is in the edge
• Trust is in the chains
• Smart contracts ?
24

25. THANK YOU!
This project has received funding from the European Union’s Horizon 2020 research
and innovation programme under grant agreement No 825184.