Wiki source code of Networks
Version 30.1 by Zenna Elfen on 2026/01/05 19:46
Hide last authors
| author | version | line-number | content |
|---|---|---|---|
 |
19.1 | 1 | (% class="jumbotron" %) |
| 2 | ((( | ||
| 3 | (% class="container" %) | ||
| 4 | ((( | ||
| |
20.1 | 5 | = Peer-for-Peer Networks = |
| |
19.1 | 6 | |
| |
20.1 | 7 | P4P, short for Peer-4-Peer (which in turn is short for Peer-for-Peer) are a family of networks which build on principles of local-first, peer-2-peer, open-source, routing agnostic (offline-first) and mutual-aid principles. The above is a lot of terms which in and of themselves carry a lot of meaning, yet when combined they enable censorship-resistant, resilient and adaptive, sustainable and energy-efficient communication infrastructures. |
| |
19.1 | 8 | ))) |
| 9 | ))) | ||
| 10 | |||
| |
27.1 | 11 | |
| |
28.1 | 12 | |
| 13 | |||
| |
29.1 | 14 | |
| 15 | |||
| |
30.1 | 16 | |
| 17 | |||
| 18 | (% class="col-xs-12 col-sm-6" %) | ||
| |
27.1 | 19 | ((( |
| 20 | {{box title="==== Contents ==== | ||
| 21 | |||
| 22 | ====== ======"}} | ||
| |
28.1 | 23 | {{toc depth="5"/}} |
| |
27.1 | 24 | {{/box}} |
| 25 | ))) | ||
| 26 | |||
| 27 | |||
| |
3.1 | 28 | (% class="box" %) |
| 29 | ((( | ||
| |
11.1 | 30 | This page contains an overview of all P4P Networks in this wiki and their building blocks. |
| 31 | |||
| 32 | You can also [[add a P4P Network>>doc:Projects.WebHome]] or have a look at the [[P4P Applications>>doc:P4P.Applications.WebHome]]. | ||
| |
3.1 | 33 | ))) |
| |
1.1 | 34 | |
| |
24.1 | 35 | |
| |
25.1 | 36 | |
| 37 | |||
| |
1.1 | 38 | |
| |
26.1 | 39 | |
| |
25.1 | 40 | ((( |
| |
11.1 | 41 | == Building Blocks of P4P Networks == |
| |
9.1 | 42 | |
| 43 | |||
| |
11.1 | 44 | (% class="box" %) |
| 45 | ((( | ||
| |
15.1 | 46 | To fully assemble a P4P network one needs a few different building blocks, below is an overview of 15 of those building blocks. Lost in translation? Take a look at the [[terminology>>doc:P4P.Definitions.WebHome]]. |
| |
11.1 | 47 | ))) |
| 48 | |||
| 49 | |||
| |
15.1 | 50 | ==== **1. Data Synchronization** ==== |
| |
11.1 | 51 | |
| |
13.1 | 52 | > Synchronization answers **how updates flow between peers** and how they determine what data to exchange. This layer is about **diffing, reconciliation, order, causality tracking, and efficient exchange**, not persistence or user-facing collaboration semantics. |
| |
11.1 | 53 | |
| |
15.1 | 54 | * //How do peers detect differences and synchronize state?// |
| 55 | * Examples: Range-Based Set Reconciliation, RIBLT, Gossip-based sync, State-based vs op-based sync, Lamport/Vector/HLC clocks, Braid Protocol | ||
| |
11.1 | 56 | |
| 57 | |||
| 58 | |||
| |
15.1 | 59 | ==== **2. Collaborative Data Structures & Conflict Resolution** ==== |
| |
11.1 | 60 | |
| |
13.1 | 61 | > This layer defines **how shared data evolves** when multiple peers edit concurrently. It focuses on **conflict-free merging, causality, and consistency of meaning**, not transport or storage. CRDTs ensure deterministic convergence, while event-sourced or stream-driven models maintain a history of all changes and derive consistent state from it. |
| 62 | |||
| |
15.1 | 63 | * //How do peers collaboratively change shared data and merge conflicts?// |
| 64 | * Examples: CRDTs (Yjs, Automerge), OT, Event Sourcing, Stream Processing, Version Vectors, Peritext | ||
| |
13.1 | 65 | |
| 66 | |||
| 67 | |||
| |
15.1 | 68 | ==== **3. Data Storage & Replication** ==== |
| |
13.1 | 69 | |
| 70 | > This layer focuses on **durability, consistency, and redundancy**. It handles write-paths, crash-resilience, and replication semantics across nodes. It is the “database/storage engine” layer where **data lives and survives over time**, independent of sync or merging logic. | ||
| 71 | |||
| |
15.1 | 72 | * //How is data persisted locally and replicated between peers?// |
| 73 | * Examples: SQLite, IndexedDB, LMDB, Hypercore (append-only logs), WALs, Merkle-DAGs (IPFS/IPLD), Blob/media storage | ||
| |
13.1 | 74 | |
| 75 | |||
| 76 | |||
| |
15.1 | 77 | ==== **4. Peer & Content Discovery** ==== |
| 78 | |||
| |
13.1 | 79 | > Discovery occurs in two phases: |
| 80 | > 1. **Peer Discovery** → finding _any_ nodes | ||
| 81 | > 2. **Topic Discovery** → finding _relevant_ nodes or resources | ||
| 82 | > These mechanisms enable decentralized bootstrapping and interest-based overlays. | ||
| 83 | |||
| |
15.1 | 84 | * //How do peers find each other, and how do they discover content in the network?// |
| 85 | * Examples: DHTs (Kademlia, Pastry), mDNS, DNS-SD, Bluetooth scanning, QR bootstrapping, static peer lists, Interest-based routing, PubSub discovery (libp2p), Rendezvous protocols | ||
| |
13.1 | 86 | |
| 87 | |||
| 88 | |||
| |
15.1 | 89 | ==== **5. Identity & Trust** ==== |
| |
13.1 | 90 | |
| 91 | > Identity systems ensure reliable mapping between peers and cryptographic keys. They underpin authorization, federated trust, and secure overlays. | ||
| 92 | |||
| |
15.1 | 93 | * //How peers identify themselves, authenticate, and establish trustworthy relationships?// |
| 94 | * Examples: PKI, Distributed Identities (DIDs), Web-of-Trust, TOFU (SSH-style), Verifiable Credentials (VCs), Peer key fingerprints (libp2p PeerIDs), Key transparency logs | ||
| |
13.1 | 95 | |
| 96 | |||
| |
16.1 | 97 | |
| |
15.1 | 98 | ==== **6. Transport Layer** ==== |
| |
13.1 | 99 | |
| |
15.1 | 100 | > This layer provides logical connections and flow control. QUIC and WebRTC bring modern congestion control and encryption defaults; Interpeer explores transport beyond IP assumptions. |
| |
13.1 | 101 | |
| |
16.1 | 102 | * //How do peers establish end-to-end byte streams and reliable delivery?// |
| |
15.1 | 103 | * Examples: TCP, UDP, QUIC, SCTP, WebRTC DataChannels, Interpeer transport stack |
| |
13.1 | 104 | |
| 105 | |||
| |
16.1 | 106 | |
| |
15.1 | 107 | ==== **7. Underlying Transport (Physical/Link Layer)** ==== |
| 108 | |||
| 109 | > Highly relevant for **offline-first / edge networks**, device-to-device communication, and mesh networks and relates to the hardware which facilitates connections. | ||
| 110 | |||
| |
16.1 | 111 | * //How does data move across the medium?// |
| |
15.1 | 112 | * Examples: Ethernet, Wi-Fi Direct / Wi-Fi Aware (post-AWDL), Bluetooth Mesh, LoRa, NFC, Cellular, CSMA/CA, TDMA, FHSS |
| 113 | |||
| |
16.1 | 114 | |
| 115 | |||
| |
15.1 | 116 | ==== **8. Session & Connection Management** ==== |
| 117 | |||
| 118 | > Manages **connection lifecycle**, including authentication handshakes, reconnection after drops, and session continuation—especially important in lossy or mobile networks. | ||
| 119 | |||
| |
16.1 | 120 | * //How are connections initiated, authenticated, resumed, and kept alive?// |
| |
15.1 | 121 | * Examples: TLS handshake semantics, Noise IK/XX patterns, session tokens, keep-alive heartbeats, reconnection strategies, session resumption tickets |
| 122 | |||
| 123 | |||
| |
16.1 | 124 | |
| |
15.1 | 125 | ==== **9. Content Addressing** ==== |
| 126 | |||
| 127 | > Content addressing ensures **immutability, verifiability, and deduplication**. Identity of data = cryptographic hash, enabling offline-first and tamper-evident systems. | ||
| 128 | |||
| |
16.1 | 129 | * //How is data addressed and verified by content, not location?// |
| |
15.1 | 130 | * Examples: IPFS CIDs, BitTorrent infohashes, Git hashes, SHA-256 addressing, Named Data Networking (NDN) |
| 131 | |||
| |
16.1 | 132 | |
| 133 | |||
| |
15.1 | 134 | ==== **10. P2P Connectivity** ==== |
| 135 | |||
| |
16.1 | 136 | > Connectivity ensures peers bypass NATs/firewalls to reach each other. |
| |
15.1 | 137 | |
| |
16.1 | 138 | * //How can two peers connect directly across networks, firewalls, and NATs?// |
| |
15.1 | 139 | * Examples: IPv6 direct, NAT Traversal, STUN, TURN, ICE (used in WebRTC), UDP hole punching, UPnP |
| 140 | |||
| |
16.1 | 141 | |
| 142 | |||
| |
15.1 | 143 | ==== **11. Session & Connection Management** ==== |
| 144 | |||
| 145 | > Manages **connection lifecycle**, including authentication handshakes, reconnection after drops, and session continuation. | ||
| 146 | |||
| |
16.1 | 147 | * //How are connections initiated, authenticated, resumed, and kept alive?// |
| |
15.1 | 148 | * Examples: TLS handshake semantics, Noise IK/XX patterns, session tokens, keep-alive heartbeats, reconnection strategies, session resumption tickets |
| 149 | |||
| |
16.1 | 150 | |
| 151 | |||
| |
15.1 | 152 | ==== **12. Message Format & Serialization** ==== |
| 153 | |||
| 154 | > Serialization ensures **portable data representation**, forward-compatible schemas, and efficient messaging. IPLD provides content-addressed structuring for P2P graph data. | ||
| 155 | |||
| |
16.1 | 156 | * //How is data encoded, structured, and made interoperable between peers?// |
| |
15.1 | 157 | * Examples: CBOR, Protocol Buffers, Cap’n Proto, JSON, ASN.1, IPLD schemas, Flatbuffers |
| 158 | |||
| |
16.1 | 159 | |
| 160 | |||
| |
15.1 | 161 | ==== **13. File / Blob Synchronization** ==== |
| 162 | |||
| 163 | > Bulk data syncing has **different trade-offs** than small collaborative state (chunking, deduplication, partial transfer, resume logic). Critical for media and archival P2P use-cases. | ||
| 164 | |||
| |
16.1 | 165 | //How are large objects transferred and deduplicated efficiently across peers?// |
| |
15.1 | 166 | Examples: BitTorrent chunking, IPFS block-store, NDN segments, rsync-style delta sync, ZFS send-receive, streaming blob transfers |
| 167 | |||
| |
16.1 | 168 | |
| |
15.1 | 169 | ==== **14. Local Storage & Processing Primitives** ==== |
| 170 | |||
| 171 | > Provides durable on-device state and local computation (event sourcing, materialization, compaction). Enables offline-first writes and deterministic replay. | ||
| 172 | |||
| |
16.1 | 173 | * //How do nodes persist, index, and process data locally—without external servers?// |
| |
15.1 | 174 | * Examples: RocksDB, LevelDB, SQLite, LMDB, local WALs/append-only logs, embedded stream processors (NATS Core JetStream mode, Actyx-like edge runtimes), Kafka-like libraries |
| 175 | |||
| 176 | |||
| |
16.1 | 177 | |
| |
15.1 | 178 | ==== **15. Crash Resilience & Abortability** ==== |
| 179 | |||
| 180 | > Ensures P2P apps don’t corrupt state on crashes. Tied to **local storage & stream-processing**, and critical in offline-first and distributed update pipelines. Abortability is the updated term for Atomicity as part of the ACID abbreviation. | ||
| 181 | |||
| |
16.1 | 182 | * //How do nodes recover and maintain correctness under failure?// |
| |
15.1 | 183 | * Examples: WALs, idempotent ops, partial log replay, transactional journaling, write fences |
| 184 | |||
| 185 | |||
| 186 | |||
| 187 | |||
| |
11.1 | 188 | == Distributed Network Types == |
| 189 | |||
| 190 | |||
| 191 | [[Flowchart depicting distributed network variants, under development. Building on work from Z. Elfen, 2024: ~[~[https:~~~~/~~~~/doi.org/10.17613/naj7d-6g984~>~>https://doi.org/10.17613/naj7d-6g984~]~]>>image:P4P_Typology.png||alt="Flowchart depicting typologies of distributed networks, such as Friend-2-Friend, Grassroots Networks, Federated Networks, Local-First, P2P and P4P Networks" data-xwiki-image-style-alignment="center" height="649" width="639"]] | ||
| 192 | |||
| 193 | |||
| |
25.1 | 194 | |
| |
24.1 | 195 | ))) |
| |
11.1 | 196 | |
| 197 | |||
| |
21.1 | 198 | ((( |
| |
24.1 | 199 | == Overview of P4P Networks == |
| |
25.1 | 200 | |
| |
22.1 | 201 | {{include reference="Projects.WebHome"/}} |
| 202 | ))) | ||
| 203 | |||
| |
23.1 | 204 |