Deltanet: a clean slate network architecture
why the name?
The “delta” in Deltanet refers to a river delta. The way topology information flows from the core to the edges of the Deltanet is like the way a river delta has channels that split and rejoin as the water flows towards the sea.
layers
Like the Internet, the Deltanet’s layers are not strictly self-contained. For instance, in both casees layer 3 depends on auxiliary application-layer protocols: BGP in the Internet, and DNTDP in the Deltanet. The layering model fits more comfortably as a guide to packet structure: each layer adds a header to the packet.
The OSI layers do not fit the Internet particularly well, and they fit the Deltanet worse. For instance, layers 4 and 5 correspond to QUIC, which has the opposite layering to TLS-over-TCP. As an attempt to reduce confusion I have given the layers different names.
| layer | name | functions |
|---|---|---|
| 2 | link | underlying network and protocols that adapt it to the Deltanet |
| 3 | node | packet forwarding; establish FIB and local RIB; propagate RIB |
| 4 | connection | construct paths; end-to-end authentication and encryption |
| 5 | stream | multipath congestion control; multiplexed data transfer |
| 6 | n/a | n/a |
| 7 | application | e.g. HTTP, DNTDP, … |
key differences from the Internet
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no addresses: instead there are cryptographic identifiers and paths
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paths are chosen by source routing, not by routers in the network
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valley-free and loop-free paths are enforced with only local knowledge
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a name lookup is necessary to discover the path to a service
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networks, routers, hosts, and ports are unified as “nodes”
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nodes are normally multihomed and connections are normally multipath
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connections bypass link failures without relying on the routing protocol
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DNTDP is a link-state protocol, not distance-vector like BGP
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the RIB is built from the FIB instead of the other way round
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the RIB distributes path characteristics: there’s no need for MTU discovery
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error reporting is out-of-band and aggregated, not in-band like ICMP
glossary
- DNTDP: Deltanet topology distribution protocol
- FIB: forwarding information base
- RIB: routing information base