Phoenix protocols#

Phoenix is an operating system made by JackMacWindows. As described in Phoenix networking, it implements custom networking akin to Rednet, with more layers in order to support inter-network communication inspired from TCP/IP.

To the user, as described in the Networking API, this is abstracted as a connected socket abstraction for both connected and disconnected transport protocols.

The layers are the following:

Layer

Protocols

Application

Address Resolution Protocol (Phoenix ARP)

Message Control Protocol (Phoenix MCP)

…

Transport

Phoenix Socket Protocol (PSP)

Network

Phoenix Internet Protocol (PIP)

Link

Phoenix Link Protocol (PLP)

See the following sections for details regarding every protocol.

Address Resolution Protocol (Phoenix ARP)#

Address Resolution Protocol (ARP) in Phoenix is a protocol for resolving IP addresses into computer IDs. It takes place on channel 0.

Packets in this protocol are tables with values depending on whether the packet is an ARP request or an ARP reply.

ARP requests have the following keys:

PhoenixNetworking (req.)

Identifies a Phoenix Networking packet. Set to true.

type (req.)

Identifies a Phoenix ARP packet. Set to "arp".

reply (req.)

Identifies a Phoenix ARP request, set to false.

source (req.)

Identifier of the source host, as a number.

sourceIP (opt.)

IP address of the source host, as a string.

destinationIP (req.)

IP address of the destination host, as a string.

ARP replies have the following keys:

PhoenixNetworking (req.)

Identifies a Phoenix Networking packet. Set to true.

type (req.)

Identifies a Phoenix ARP packet. Set to "arp".

reply (req.)

Identifies a Phoenix ARP reply, set to true.

source (req.)

Identifier of the source host, as a number.

sourceIP (req.)

IP address of the source host, as a string.

destination (req.)

Identifier of the destination host, as a number.

This is a copy of the source field from the request.

destinationIP (opt.)

IP address of the destination host, as a string.

This is a copy of the sourceIP field from the request, if present.

When receiving an ARP request, a host must reply if the following conditions are met:

  • destinationIP corresponds to the IP address of the interface or device on which the ARP request has been received.

  • Either sourceIP if unset, or is different from destinationIP.

The reply must copy source and sourceIP into the destination and destinationIP fields respectively, and source and sourceIP must be set to the current host’s numerical identifier and IP address.

This protocol must only be used for one use case: resolve an IP address into a numerical host identifier. It cannot be used to discover all neighbours and their IP addresses[1].

Phoenix Internet Protocol (PIP)#

Phoenix Internet Protocol (PIP) is protocol implementing a packet-switched network over Phoenix Link Protocol (PLP). It allows sending datagrams from one host to another, representing hosts as IPv4-like addresses.

Packets in this protocol are tables with the following properties:

PhoenixNetworking (req.)

Identifies a Phoenix Networking packet. Set to true.

type (req.)

Identifies a PIP packet. Set to "internet".

messageID

Identifier for the message, as a string or number.

This allows discarding duplicate messages.

source (req.)

IP address of the host sending a message.

destination (req.)

IP address of the host which should receive the message.

hopsLeft (req.)

Number of hops left.

payload (req.)

Payload of the protocol above, assumed to contain at least the following properties:

PhoenixNetworking

Identifiers a Phoenix Networking packet. Set to true.

type

Protocol or type of the carried payload.

In its simplest version, upon receiving a PIP packet, a host should read the payload if the destination corresponds to the host’s IP address, and discard it otherwise.

In order to know to which host to send an IP packet, i.e. determine the next “hop”, a host must have a routing table with rules depending on the destination and source. You can inspire yourself from Phoenix’s routing table format with routelist.

Message Control Protocol (Phoenix MCP)#

Message Control Protocol (MCP) in Phoenix is a protocol for determining if a host with a given IP address is up and accessible, or not.

Packets in this protocol are tables with the following properties:

PhoenixNetworking (req.)

Identifies a Phoenix Networking packet. Set to true.

type (req.)

Identifies an MCP packet. Set to "control".

messageType (req.)

Message type, as a string among the following:

"ping"

Indicates a ping request, which should be replied with a subsequent "pong" message.

"pong"

Indicates a reply to a previous ping request.

Note

If the original value from the destination host is known, hopsLeft from the surrounding PIP packet can help the host that emitted the ping determine the number of hosts.

By default, Phoenix uses 15 hops on its PIP packets.

"unreachable"

Indicates that a previous message was unable to be sent to the destination.

"timeout"

Indicates that a previous message was rerouted too many times, and was subsequently rejected.

error (opt.)

If set, can be a string providing additional information on why the message was sent.

This is targeted towards developers, and should not be parsed.

In its simplest form, upon receiving an MCP "ping" packet, a host should answer with an MCP "pong" packet.

Phoenix Socket Protocol (PSP)#

Phoenix Socket Protocol (PSP) is a protocol for establishing a connection over Phoenix Internet Protocol (PIP).

Todo

Write this!