Minor: tweaks to the discussion of network parameters and network map.

This commit is contained in:
Mike Hearn 2018-01-15 18:44:41 +01:00
parent 55b7035a44
commit d247e643ae

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@ -2,7 +2,7 @@ Network Map
===========
The network map is a collection of signed ``NodeInfo`` objects (signed by the node it represents and thus tamper-proof)
forming the set of reachable nodes in a compatbility zone. A node can receive these objects from two sources:
forming the set of reachable nodes in a compatibility zone. A node can receive these objects from two sources:
1. The HTTP network map service if the ``compatibilityZoneURL`` config key is specified.
2. The ``additional-node-infos`` directory within the node's directory.
@ -13,7 +13,7 @@ HTTP network map service
If the node is configured with the ``compatibilityZoneURL`` config then it first uploads its own signed ``NodeInfo``
to the server (and each time it changes on startup) and then proceeds to download the entire network map. The network map
consists of a list of ``NodeInfo`` hashes. The node periodically polls for the network map (based on the HTTP cache expiry
header) and any new hash entries are downloaded and cached. Entries which no longer exist are deleted from the node's cache.
header) and any new entries are downloaded and cached. Entries which no longer exist are deleted from the node's cache.
The set of REST end-points for the network map service are as follows.
@ -35,7 +35,7 @@ The ``additional-node-infos`` directory
Alongside the HTTP network map service, or as a replacement if the node isn't connected to one, the node polls the
contents of the ``additional-node-infos`` directory located in its base directory. Each file is expected to be the same
signed ``NodeInfo`` object that the network map service vends. These are automtically added to the node's cache and can
signed ``NodeInfo`` object that the network map service vends. These are automatically added to the node's cache and can
be used to supplement or replace the HTTP network map. If the same node is advertised through both mechanisms then the
latest one is taken.
@ -46,7 +46,7 @@ of every node that's part of this network.
Network parameters
------------------
Network parameters are a set of values that every node participating in the network needs to agree on and use to
Network parameters are a set of values that every node participating in the zone needs to agree on and use to
correctly interoperate with each other. If the node is using the HTTP network map service then on first startup it will
download the signed network parameters, cache it in a ``network-parameters`` file and apply them on the node.
@ -54,7 +54,7 @@ download the signed network parameters, cache it in a ``network-parameters`` fil
then the node will automatically shutdown. Resolution to this is to delete the incorrect file and restart the node so
that the parameters can be downloaded again.
.. note:: A future release will support the notion of network parameters changes.
.. note:: A future release will support the notion of phased rollout of network parameter changes.
If the node isn't using a HTTP network map service then it's expected the signed file is provided by some other means.
For such a scenario there is the network bootstrapper tool which in addition to generating the network parameters file
@ -66,13 +66,14 @@ The current set of network parameters:
not start.
:notaries: List of identity and validation type (either validating or non-validating) of the notaries which are permitted
in the compatibility zone.
:maxMessageSize: Maximum allowed P2P message size sent over the wire in bytes. Any message larger than this will be
split up.
:maxTransactionSize: Maximum permitted transaction size in bytes.
:maxMessageSize: Maximum allowed size in bytes of an individual message sent over the wire. Note that attachments are
a special case and may be fragmented for streaming transfer, however, an individual transaction or flow message
may not be larger than this value.
:modifiedTime: The time when the network parameters were last modified by the compatibility zone operator.
:epoch: Version number of the network parameters. Starting from 1, this will always increment whenever any of the
parameters change.
.. note:: ``maxTransactionSize`` is currently not enforced in the node, but will be in a later release.
More parameters may be added in future releases.
More parameters will be added in future releases to regulate things like allowed port numbers, how long a node can be
offline before it is evicted from the zone, whether or not IPv6 connectivity is required for zone members, required
cryptographic algorithms and rollout schedules (e.g. for moving to post quantum cryptography), parameters related to
SGX and so on.