2023-02-07 23:22:28 +00:00
# Deneb -- Networking
2022-03-10 05:31:11 +00:00
2023-02-07 23:22:28 +00:00
This document contains the consensus-layer networking specification for Deneb.
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The specification of these changes continues in the same format as the network specifications of previous upgrades, and assumes them as pre-requisite.
## Table of contents
<!-- TOC -->
<!-- START doctoc generated TOC please keep comment here to allow auto update -->
<!-- DON'T EDIT THIS SECTION, INSTEAD RE - RUN doctoc TO UPDATE -->
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- [Configuration ](#configuration )
- [Containers ](#containers )
- [`BlobSidecar` ](#blobsidecar )
- [`SignedBlobSidecar` ](#signedblobsidecar )
- [The gossip domain: gossipsub ](#the-gossip-domain-gossipsub )
- [Topics and messages ](#topics-and-messages )
- [Global topics ](#global-topics )
- [`beacon_block` ](#beacon_block )
- [`blob_sidecar_{index}` ](#blob_sidecar_index )
- [Transitioning the gossip ](#transitioning-the-gossip )
- [The Req/Resp domain ](#the-reqresp-domain )
- [Messages ](#messages )
- [BeaconBlocksByRange v2 ](#beaconblocksbyrange-v2 )
- [BeaconBlocksByRoot v2 ](#beaconblocksbyroot-v2 )
- [BlobSidecarsByRoot v1 ](#blobsidecarsbyroot-v1 )
- [BlobSidecarsByRange v1 ](#blobsidecarsbyrange-v1 )
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- [Design decision rationale ](#design-decision-rationale )
- [Why are blobs relayed as a sidecar, separate from beacon blocks? ](#why-are-blobs-relayed-as-a-sidecar-separate-from-beacon-blocks )
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<!-- END doctoc generated TOC please keep comment here to allow auto update -->
<!-- /TOC -->
## Configuration
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| Name | Value | Description |
|------------------------------------------|-----------------------------------|---------------------------------------------------------------------|
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| `MAX_REQUEST_BLOCKS_DENEB` | `2**7` (= 128) | Maximum number of blocks in a single request |
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| `MAX_REQUEST_BLOB_SIDECARS` | `2**7` (= 128) | Maximum number of blob sidecars in a single request |
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| `MIN_EPOCHS_FOR_BLOBS_SIDECARS_REQUESTS` | `2**12` (= 4096 epochs, ~18 days) | The minimum epoch range over which a node must serve blobs sidecars |
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## Containers
Free the blobs
This PR reintroduces and further decouples blocks and blobs in EIP-4844,
so as to improve network and processing performance.
Block and blob processing, for the purpose of gossip validation, are
independent: they can both be propagated and gossip-validated
in parallel - the decoupled design allows 4 important optimizations
(or, if you are so inclined, removes 4 unnecessary pessimizations):
* Blocks and blobs travel on independent meshes allowing for better
parallelization and utilization of high-bandwidth peers
* Re-broadcasting after validation can start earlier allowing more
efficient use of upload bandwidth - blocks for example can be
rebroadcast to peers while blobs are still being downloaded
* bandwidth-reduction techniques such as per-peer deduplication are more
efficient because of the smaller message size
* gossip verification happens independently for blocks and blobs,
allowing better sharing / use of CPU and I/O resources in clients
With growing block sizes and additional blob data to stream, the network
streaming time becomes a dominant factor in propagation times - on a
100mbit line, streaming 1mb to 8 peers takes ~1s - this process is
repeated for each hop in both incoming and outgoing directions.
This design in particular sends each blob on a separate subnet, thus
maximising the potential for parallelisation and providing a natural
path for growing the number of blobs per block should the network be
judged to be able to handle it.
Changes compared to the current design include:
* `BlobsSidecar` is split into individual `BlobSidecar` containers -
each container is signed individually by the proposer
* the signature is used during gossip validation but later dropped.
* KZG commitment verification is moved out of the gossip pipeline and
instead done before fork choice addition, when both block and sidecars
have arrived
* clients may verify individual blob commitments earlier
* more generally and similar to block verification, gossip propagation
is performed solely based on trivial consistency checks and proposer
signature verification
* by-root blob requests are done per-blob, so as to retain the ability
to fill in blobs one-by-one assuming clients generally receive blobs
from gossip
* by-range blob requests are done per-block, so as to simplify
historical sync
* range and root requests are limited to `128` entries for both blocks
and blobs - practically, the current higher limit of `1024` for blocks
does not get used and keeping the limits consistent simplifies
implementation - with the merge, block sizes have grown significantly
and clients generally fetch smaller chunks.
2023-02-07 09:55:51 +00:00
### `BlobSidecar`
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```python
Free the blobs
This PR reintroduces and further decouples blocks and blobs in EIP-4844,
so as to improve network and processing performance.
Block and blob processing, for the purpose of gossip validation, are
independent: they can both be propagated and gossip-validated
in parallel - the decoupled design allows 4 important optimizations
(or, if you are so inclined, removes 4 unnecessary pessimizations):
* Blocks and blobs travel on independent meshes allowing for better
parallelization and utilization of high-bandwidth peers
* Re-broadcasting after validation can start earlier allowing more
efficient use of upload bandwidth - blocks for example can be
rebroadcast to peers while blobs are still being downloaded
* bandwidth-reduction techniques such as per-peer deduplication are more
efficient because of the smaller message size
* gossip verification happens independently for blocks and blobs,
allowing better sharing / use of CPU and I/O resources in clients
With growing block sizes and additional blob data to stream, the network
streaming time becomes a dominant factor in propagation times - on a
100mbit line, streaming 1mb to 8 peers takes ~1s - this process is
repeated for each hop in both incoming and outgoing directions.
This design in particular sends each blob on a separate subnet, thus
maximising the potential for parallelisation and providing a natural
path for growing the number of blobs per block should the network be
judged to be able to handle it.
Changes compared to the current design include:
* `BlobsSidecar` is split into individual `BlobSidecar` containers -
each container is signed individually by the proposer
* the signature is used during gossip validation but later dropped.
* KZG commitment verification is moved out of the gossip pipeline and
instead done before fork choice addition, when both block and sidecars
have arrived
* clients may verify individual blob commitments earlier
* more generally and similar to block verification, gossip propagation
is performed solely based on trivial consistency checks and proposer
signature verification
* by-root blob requests are done per-blob, so as to retain the ability
to fill in blobs one-by-one assuming clients generally receive blobs
from gossip
* by-range blob requests are done per-block, so as to simplify
historical sync
* range and root requests are limited to `128` entries for both blocks
and blobs - practically, the current higher limit of `1024` for blocks
does not get used and keeping the limits consistent simplifies
implementation - with the merge, block sizes have grown significantly
and clients generally fetch smaller chunks.
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class BlobSidecar(Container):
block_root: Root
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index: BlobIndex # Index of blob in block
Free the blobs
This PR reintroduces and further decouples blocks and blobs in EIP-4844,
so as to improve network and processing performance.
Block and blob processing, for the purpose of gossip validation, are
independent: they can both be propagated and gossip-validated
in parallel - the decoupled design allows 4 important optimizations
(or, if you are so inclined, removes 4 unnecessary pessimizations):
* Blocks and blobs travel on independent meshes allowing for better
parallelization and utilization of high-bandwidth peers
* Re-broadcasting after validation can start earlier allowing more
efficient use of upload bandwidth - blocks for example can be
rebroadcast to peers while blobs are still being downloaded
* bandwidth-reduction techniques such as per-peer deduplication are more
efficient because of the smaller message size
* gossip verification happens independently for blocks and blobs,
allowing better sharing / use of CPU and I/O resources in clients
With growing block sizes and additional blob data to stream, the network
streaming time becomes a dominant factor in propagation times - on a
100mbit line, streaming 1mb to 8 peers takes ~1s - this process is
repeated for each hop in both incoming and outgoing directions.
This design in particular sends each blob on a separate subnet, thus
maximising the potential for parallelisation and providing a natural
path for growing the number of blobs per block should the network be
judged to be able to handle it.
Changes compared to the current design include:
* `BlobsSidecar` is split into individual `BlobSidecar` containers -
each container is signed individually by the proposer
* the signature is used during gossip validation but later dropped.
* KZG commitment verification is moved out of the gossip pipeline and
instead done before fork choice addition, when both block and sidecars
have arrived
* clients may verify individual blob commitments earlier
* more generally and similar to block verification, gossip propagation
is performed solely based on trivial consistency checks and proposer
signature verification
* by-root blob requests are done per-blob, so as to retain the ability
to fill in blobs one-by-one assuming clients generally receive blobs
from gossip
* by-range blob requests are done per-block, so as to simplify
historical sync
* range and root requests are limited to `128` entries for both blocks
and blobs - practically, the current higher limit of `1024` for blocks
does not get used and keeping the limits consistent simplifies
implementation - with the merge, block sizes have grown significantly
and clients generally fetch smaller chunks.
2023-02-07 09:55:51 +00:00
slot: Slot
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block_parent_root: Root # Proposer shuffling determinant
Free the blobs
This PR reintroduces and further decouples blocks and blobs in EIP-4844,
so as to improve network and processing performance.
Block and blob processing, for the purpose of gossip validation, are
independent: they can both be propagated and gossip-validated
in parallel - the decoupled design allows 4 important optimizations
(or, if you are so inclined, removes 4 unnecessary pessimizations):
* Blocks and blobs travel on independent meshes allowing for better
parallelization and utilization of high-bandwidth peers
* Re-broadcasting after validation can start earlier allowing more
efficient use of upload bandwidth - blocks for example can be
rebroadcast to peers while blobs are still being downloaded
* bandwidth-reduction techniques such as per-peer deduplication are more
efficient because of the smaller message size
* gossip verification happens independently for blocks and blobs,
allowing better sharing / use of CPU and I/O resources in clients
With growing block sizes and additional blob data to stream, the network
streaming time becomes a dominant factor in propagation times - on a
100mbit line, streaming 1mb to 8 peers takes ~1s - this process is
repeated for each hop in both incoming and outgoing directions.
This design in particular sends each blob on a separate subnet, thus
maximising the potential for parallelisation and providing a natural
path for growing the number of blobs per block should the network be
judged to be able to handle it.
Changes compared to the current design include:
* `BlobsSidecar` is split into individual `BlobSidecar` containers -
each container is signed individually by the proposer
* the signature is used during gossip validation but later dropped.
* KZG commitment verification is moved out of the gossip pipeline and
instead done before fork choice addition, when both block and sidecars
have arrived
* clients may verify individual blob commitments earlier
* more generally and similar to block verification, gossip propagation
is performed solely based on trivial consistency checks and proposer
signature verification
* by-root blob requests are done per-blob, so as to retain the ability
to fill in blobs one-by-one assuming clients generally receive blobs
from gossip
* by-range blob requests are done per-block, so as to simplify
historical sync
* range and root requests are limited to `128` entries for both blocks
and blobs - practically, the current higher limit of `1024` for blocks
does not get used and keeping the limits consistent simplifies
implementation - with the merge, block sizes have grown significantly
and clients generally fetch smaller chunks.
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proposer_index: ValidatorIndex
blob: Blob
kzg_commitment: KZGCommitment
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kzg_proof: KZGProof # Allows for quick verification of kzg_commitment
Free the blobs
This PR reintroduces and further decouples blocks and blobs in EIP-4844,
so as to improve network and processing performance.
Block and blob processing, for the purpose of gossip validation, are
independent: they can both be propagated and gossip-validated
in parallel - the decoupled design allows 4 important optimizations
(or, if you are so inclined, removes 4 unnecessary pessimizations):
* Blocks and blobs travel on independent meshes allowing for better
parallelization and utilization of high-bandwidth peers
* Re-broadcasting after validation can start earlier allowing more
efficient use of upload bandwidth - blocks for example can be
rebroadcast to peers while blobs are still being downloaded
* bandwidth-reduction techniques such as per-peer deduplication are more
efficient because of the smaller message size
* gossip verification happens independently for blocks and blobs,
allowing better sharing / use of CPU and I/O resources in clients
With growing block sizes and additional blob data to stream, the network
streaming time becomes a dominant factor in propagation times - on a
100mbit line, streaming 1mb to 8 peers takes ~1s - this process is
repeated for each hop in both incoming and outgoing directions.
This design in particular sends each blob on a separate subnet, thus
maximising the potential for parallelisation and providing a natural
path for growing the number of blobs per block should the network be
judged to be able to handle it.
Changes compared to the current design include:
* `BlobsSidecar` is split into individual `BlobSidecar` containers -
each container is signed individually by the proposer
* the signature is used during gossip validation but later dropped.
* KZG commitment verification is moved out of the gossip pipeline and
instead done before fork choice addition, when both block and sidecars
have arrived
* clients may verify individual blob commitments earlier
* more generally and similar to block verification, gossip propagation
is performed solely based on trivial consistency checks and proposer
signature verification
* by-root blob requests are done per-blob, so as to retain the ability
to fill in blobs one-by-one assuming clients generally receive blobs
from gossip
* by-range blob requests are done per-block, so as to simplify
historical sync
* range and root requests are limited to `128` entries for both blocks
and blobs - practically, the current higher limit of `1024` for blocks
does not get used and keeping the limits consistent simplifies
implementation - with the merge, block sizes have grown significantly
and clients generally fetch smaller chunks.
2023-02-07 09:55:51 +00:00
```
### `SignedBlobSidecar`
```python
class SignedBlobSidecar(Container):
message: BlobSidecar
signature: Signature
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```
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## The gossip domain: gossipsub
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Some gossip meshes are upgraded in the fork of Deneb to support upgraded types.
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### Topics and messages
Topics follow the same specification as in prior upgrades.
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The `beacon_block` topic is modified to also support deneb blocks and new topics are added per table below. All other topics remain stable.
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The specification around the creation, validation, and dissemination of messages has not changed from the Capella document unless explicitly noted here.
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The derivation of the `message-id` remains stable.
The new topics along with the type of the `data` field of a gossipsub message are given in this table:
| Name | Message Type |
| - | - |
Free the blobs
This PR reintroduces and further decouples blocks and blobs in EIP-4844,
so as to improve network and processing performance.
Block and blob processing, for the purpose of gossip validation, are
independent: they can both be propagated and gossip-validated
in parallel - the decoupled design allows 4 important optimizations
(or, if you are so inclined, removes 4 unnecessary pessimizations):
* Blocks and blobs travel on independent meshes allowing for better
parallelization and utilization of high-bandwidth peers
* Re-broadcasting after validation can start earlier allowing more
efficient use of upload bandwidth - blocks for example can be
rebroadcast to peers while blobs are still being downloaded
* bandwidth-reduction techniques such as per-peer deduplication are more
efficient because of the smaller message size
* gossip verification happens independently for blocks and blobs,
allowing better sharing / use of CPU and I/O resources in clients
With growing block sizes and additional blob data to stream, the network
streaming time becomes a dominant factor in propagation times - on a
100mbit line, streaming 1mb to 8 peers takes ~1s - this process is
repeated for each hop in both incoming and outgoing directions.
This design in particular sends each blob on a separate subnet, thus
maximising the potential for parallelisation and providing a natural
path for growing the number of blobs per block should the network be
judged to be able to handle it.
Changes compared to the current design include:
* `BlobsSidecar` is split into individual `BlobSidecar` containers -
each container is signed individually by the proposer
* the signature is used during gossip validation but later dropped.
* KZG commitment verification is moved out of the gossip pipeline and
instead done before fork choice addition, when both block and sidecars
have arrived
* clients may verify individual blob commitments earlier
* more generally and similar to block verification, gossip propagation
is performed solely based on trivial consistency checks and proposer
signature verification
* by-root blob requests are done per-blob, so as to retain the ability
to fill in blobs one-by-one assuming clients generally receive blobs
from gossip
* by-range blob requests are done per-block, so as to simplify
historical sync
* range and root requests are limited to `128` entries for both blocks
and blobs - practically, the current higher limit of `1024` for blocks
does not get used and keeping the limits consistent simplifies
implementation - with the merge, block sizes have grown significantly
and clients generally fetch smaller chunks.
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| `blob_sidecar_{index}` | `SignedBlobSidecar` (new) |
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#### Global topics
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Deneb introduces new global topics for blob sidecars.
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##### `beacon_block`
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The *type* of the payload of this topic changes to the (modified) `SignedBeaconBlock` found in deneb.
2022-11-08 18:44:41 +00:00
Free the blobs
This PR reintroduces and further decouples blocks and blobs in EIP-4844,
so as to improve network and processing performance.
Block and blob processing, for the purpose of gossip validation, are
independent: they can both be propagated and gossip-validated
in parallel - the decoupled design allows 4 important optimizations
(or, if you are so inclined, removes 4 unnecessary pessimizations):
* Blocks and blobs travel on independent meshes allowing for better
parallelization and utilization of high-bandwidth peers
* Re-broadcasting after validation can start earlier allowing more
efficient use of upload bandwidth - blocks for example can be
rebroadcast to peers while blobs are still being downloaded
* bandwidth-reduction techniques such as per-peer deduplication are more
efficient because of the smaller message size
* gossip verification happens independently for blocks and blobs,
allowing better sharing / use of CPU and I/O resources in clients
With growing block sizes and additional blob data to stream, the network
streaming time becomes a dominant factor in propagation times - on a
100mbit line, streaming 1mb to 8 peers takes ~1s - this process is
repeated for each hop in both incoming and outgoing directions.
This design in particular sends each blob on a separate subnet, thus
maximising the potential for parallelisation and providing a natural
path for growing the number of blobs per block should the network be
judged to be able to handle it.
Changes compared to the current design include:
* `BlobsSidecar` is split into individual `BlobSidecar` containers -
each container is signed individually by the proposer
* the signature is used during gossip validation but later dropped.
* KZG commitment verification is moved out of the gossip pipeline and
instead done before fork choice addition, when both block and sidecars
have arrived
* clients may verify individual blob commitments earlier
* more generally and similar to block verification, gossip propagation
is performed solely based on trivial consistency checks and proposer
signature verification
* by-root blob requests are done per-blob, so as to retain the ability
to fill in blobs one-by-one assuming clients generally receive blobs
from gossip
* by-range blob requests are done per-block, so as to simplify
historical sync
* range and root requests are limited to `128` entries for both blocks
and blobs - practically, the current higher limit of `1024` for blocks
does not get used and keeping the limits consistent simplifies
implementation - with the merge, block sizes have grown significantly
and clients generally fetch smaller chunks.
2023-02-07 09:55:51 +00:00
##### `blob_sidecar_{index}`
2022-11-15 17:29:03 +00:00
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This topic is used to propagate signed blob sidecars, one for each sidecar index. The number of indices is defined by `MAX_BLOBS_PER_BLOCK` .
2022-03-10 05:31:11 +00:00
Free the blobs
This PR reintroduces and further decouples blocks and blobs in EIP-4844,
so as to improve network and processing performance.
Block and blob processing, for the purpose of gossip validation, are
independent: they can both be propagated and gossip-validated
in parallel - the decoupled design allows 4 important optimizations
(or, if you are so inclined, removes 4 unnecessary pessimizations):
* Blocks and blobs travel on independent meshes allowing for better
parallelization and utilization of high-bandwidth peers
* Re-broadcasting after validation can start earlier allowing more
efficient use of upload bandwidth - blocks for example can be
rebroadcast to peers while blobs are still being downloaded
* bandwidth-reduction techniques such as per-peer deduplication are more
efficient because of the smaller message size
* gossip verification happens independently for blocks and blobs,
allowing better sharing / use of CPU and I/O resources in clients
With growing block sizes and additional blob data to stream, the network
streaming time becomes a dominant factor in propagation times - on a
100mbit line, streaming 1mb to 8 peers takes ~1s - this process is
repeated for each hop in both incoming and outgoing directions.
This design in particular sends each blob on a separate subnet, thus
maximising the potential for parallelisation and providing a natural
path for growing the number of blobs per block should the network be
judged to be able to handle it.
Changes compared to the current design include:
* `BlobsSidecar` is split into individual `BlobSidecar` containers -
each container is signed individually by the proposer
* the signature is used during gossip validation but later dropped.
* KZG commitment verification is moved out of the gossip pipeline and
instead done before fork choice addition, when both block and sidecars
have arrived
* clients may verify individual blob commitments earlier
* more generally and similar to block verification, gossip propagation
is performed solely based on trivial consistency checks and proposer
signature verification
* by-root blob requests are done per-blob, so as to retain the ability
to fill in blobs one-by-one assuming clients generally receive blobs
from gossip
* by-range blob requests are done per-block, so as to simplify
historical sync
* range and root requests are limited to `128` entries for both blocks
and blobs - practically, the current higher limit of `1024` for blocks
does not get used and keeping the limits consistent simplifies
implementation - with the merge, block sizes have grown significantly
and clients generally fetch smaller chunks.
2023-02-07 09:55:51 +00:00
The following validations MUST pass before forwarding the `sidecar` on the network, assuming the alias `sidecar = signed_blob_sidecar.message` :
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- _[REJECT]_ The sidecar is for the correct topic -- i.e. `sidecar.index` matches the topic `{index}` .
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- _[IGNORE]_ The sidecar is not from a future slot (with a `MAXIMUM_GOSSIP_CLOCK_DISPARITY` allowance) -- i.e. validate that `sidecar.slot <= current_slot` (a client MAY queue future blocks for processing at the appropriate slot).
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- _[IGNORE]_ The sidecar is from a slot greater than the latest finalized slot -- i.e. validate that `sidecar.slot > compute_start_slot_at_epoch(state.finalized_checkpoint.epoch)`
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- _[IGNORE]_ The blob's block's parent (defined by `sidecar.block_parent_root` ) has been seen (via both gossip and non-gossip sources) (a client MAY queue blocks for processing once the parent block is retrieved).
Free the blobs
This PR reintroduces and further decouples blocks and blobs in EIP-4844,
so as to improve network and processing performance.
Block and blob processing, for the purpose of gossip validation, are
independent: they can both be propagated and gossip-validated
in parallel - the decoupled design allows 4 important optimizations
(or, if you are so inclined, removes 4 unnecessary pessimizations):
* Blocks and blobs travel on independent meshes allowing for better
parallelization and utilization of high-bandwidth peers
* Re-broadcasting after validation can start earlier allowing more
efficient use of upload bandwidth - blocks for example can be
rebroadcast to peers while blobs are still being downloaded
* bandwidth-reduction techniques such as per-peer deduplication are more
efficient because of the smaller message size
* gossip verification happens independently for blocks and blobs,
allowing better sharing / use of CPU and I/O resources in clients
With growing block sizes and additional blob data to stream, the network
streaming time becomes a dominant factor in propagation times - on a
100mbit line, streaming 1mb to 8 peers takes ~1s - this process is
repeated for each hop in both incoming and outgoing directions.
This design in particular sends each blob on a separate subnet, thus
maximising the potential for parallelisation and providing a natural
path for growing the number of blobs per block should the network be
judged to be able to handle it.
Changes compared to the current design include:
* `BlobsSidecar` is split into individual `BlobSidecar` containers -
each container is signed individually by the proposer
* the signature is used during gossip validation but later dropped.
* KZG commitment verification is moved out of the gossip pipeline and
instead done before fork choice addition, when both block and sidecars
have arrived
* clients may verify individual blob commitments earlier
* more generally and similar to block verification, gossip propagation
is performed solely based on trivial consistency checks and proposer
signature verification
* by-root blob requests are done per-blob, so as to retain the ability
to fill in blobs one-by-one assuming clients generally receive blobs
from gossip
* by-range blob requests are done per-block, so as to simplify
historical sync
* range and root requests are limited to `128` entries for both blocks
and blobs - practically, the current higher limit of `1024` for blocks
does not get used and keeping the limits consistent simplifies
implementation - with the merge, block sizes have grown significantly
and clients generally fetch smaller chunks.
2023-02-07 09:55:51 +00:00
- _[REJECT]_ The proposer signature, `signed_blob_sidecar.signature` , is valid with respect to the `sidecar.proposer_index` pubkey.
- _[IGNORE]_ The sidecar is the only sidecar with valid signature received for the tuple `(sidecar.slot, sidecar.proposer_index, sidecar.index)` .
-- Clients MUST discard blocks where multiple sidecars for the same proposer and index have been observed.
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- _[REJECT]_ The sidecar is proposed by the expected `proposer_index` for the block's slot in the context of the current shuffling (defined by `block_parent_root` /`slot`).
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If the `proposer_index` cannot immediately be verified against the expected shuffling, the sidecar MAY be queued for later processing while proposers for the block's branch are calculated -- in such a case _do not_ `REJECT` , instead `IGNORE` this message.
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2023-02-14 13:18:29 +00:00
2022-03-10 05:31:11 +00:00
### Transitioning the gossip
See gossip transition details found in the [Altair document ](../altair/p2p-interface.md#transitioning-the-gossip ) for
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details on how to handle transitioning gossip topics for this upgrade.
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## The Req/Resp domain
### Messages
#### BeaconBlocksByRange v2
**Protocol ID:** `/eth2/beacon_chain/req/beacon_blocks_by_range/2/`
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The Deneb fork-digest is introduced to the `context` enum to specify Deneb beacon block type.
2022-03-10 05:31:11 +00:00
Per `context = compute_fork_digest(fork_version, genesis_validators_root)` :
[0]: # (eth2spec: skip)
| `fork_version` | Chunk SSZ type |
|--------------------------|-------------------------------|
| `GENESIS_FORK_VERSION` | `phase0.SignedBeaconBlock` |
| `ALTAIR_FORK_VERSION` | `altair.SignedBeaconBlock` |
| `BELLATRIX_FORK_VERSION` | `bellatrix.SignedBeaconBlock` |
2022-11-08 14:06:38 +00:00
| `CAPELLA_FORK_VERSION` | `capella.SignedBeaconBlock` |
2023-01-23 14:08:34 +00:00
| `DENEB_FORK_VERSION` | `deneb.SignedBeaconBlock` |
2022-03-10 05:31:11 +00:00
2023-02-10 09:44:31 +00:00
No more than `MAX_REQUEST_BLOCKS_DENEB` may be requested at a time.
Free the blobs
This PR reintroduces and further decouples blocks and blobs in EIP-4844,
so as to improve network and processing performance.
Block and blob processing, for the purpose of gossip validation, are
independent: they can both be propagated and gossip-validated
in parallel - the decoupled design allows 4 important optimizations
(or, if you are so inclined, removes 4 unnecessary pessimizations):
* Blocks and blobs travel on independent meshes allowing for better
parallelization and utilization of high-bandwidth peers
* Re-broadcasting after validation can start earlier allowing more
efficient use of upload bandwidth - blocks for example can be
rebroadcast to peers while blobs are still being downloaded
* bandwidth-reduction techniques such as per-peer deduplication are more
efficient because of the smaller message size
* gossip verification happens independently for blocks and blobs,
allowing better sharing / use of CPU and I/O resources in clients
With growing block sizes and additional blob data to stream, the network
streaming time becomes a dominant factor in propagation times - on a
100mbit line, streaming 1mb to 8 peers takes ~1s - this process is
repeated for each hop in both incoming and outgoing directions.
This design in particular sends each blob on a separate subnet, thus
maximising the potential for parallelisation and providing a natural
path for growing the number of blobs per block should the network be
judged to be able to handle it.
Changes compared to the current design include:
* `BlobsSidecar` is split into individual `BlobSidecar` containers -
each container is signed individually by the proposer
* the signature is used during gossip validation but later dropped.
* KZG commitment verification is moved out of the gossip pipeline and
instead done before fork choice addition, when both block and sidecars
have arrived
* clients may verify individual blob commitments earlier
* more generally and similar to block verification, gossip propagation
is performed solely based on trivial consistency checks and proposer
signature verification
* by-root blob requests are done per-blob, so as to retain the ability
to fill in blobs one-by-one assuming clients generally receive blobs
from gossip
* by-range blob requests are done per-block, so as to simplify
historical sync
* range and root requests are limited to `128` entries for both blocks
and blobs - practically, the current higher limit of `1024` for blocks
does not get used and keeping the limits consistent simplifies
implementation - with the merge, block sizes have grown significantly
and clients generally fetch smaller chunks.
2023-02-07 09:55:51 +00:00
2022-03-10 05:31:11 +00:00
#### BeaconBlocksByRoot v2
**Protocol ID:** `/eth2/beacon_chain/req/beacon_blocks_by_root/2/`
Per `context = compute_fork_digest(fork_version, genesis_validators_root)` :
[1]: # (eth2spec: skip)
2022-12-13 16:07:37 +00:00
| `fork_version` | Chunk SSZ type |
|--------------------------|-------------------------------|
| `GENESIS_FORK_VERSION` | `phase0.SignedBeaconBlock` |
| `ALTAIR_FORK_VERSION` | `altair.SignedBeaconBlock` |
2022-03-10 05:31:11 +00:00
| `BELLATRIX_FORK_VERSION` | `bellatrix.SignedBeaconBlock` |
2022-11-08 14:06:38 +00:00
| `CAPELLA_FORK_VERSION` | `capella.SignedBeaconBlock` |
2023-02-10 10:16:51 +00:00
| `DENEB_FORK_VERSION` | `deneb.SignedBeaconBlock` |
2022-03-10 05:31:11 +00:00
2023-02-10 09:44:31 +00:00
No more than `MAX_REQUEST_BLOCKS_DENEB` may be requested at a time.
2022-03-10 05:31:11 +00:00
Free the blobs
This PR reintroduces and further decouples blocks and blobs in EIP-4844,
so as to improve network and processing performance.
Block and blob processing, for the purpose of gossip validation, are
independent: they can both be propagated and gossip-validated
in parallel - the decoupled design allows 4 important optimizations
(or, if you are so inclined, removes 4 unnecessary pessimizations):
* Blocks and blobs travel on independent meshes allowing for better
parallelization and utilization of high-bandwidth peers
* Re-broadcasting after validation can start earlier allowing more
efficient use of upload bandwidth - blocks for example can be
rebroadcast to peers while blobs are still being downloaded
* bandwidth-reduction techniques such as per-peer deduplication are more
efficient because of the smaller message size
* gossip verification happens independently for blocks and blobs,
allowing better sharing / use of CPU and I/O resources in clients
With growing block sizes and additional blob data to stream, the network
streaming time becomes a dominant factor in propagation times - on a
100mbit line, streaming 1mb to 8 peers takes ~1s - this process is
repeated for each hop in both incoming and outgoing directions.
This design in particular sends each blob on a separate subnet, thus
maximising the potential for parallelisation and providing a natural
path for growing the number of blobs per block should the network be
judged to be able to handle it.
Changes compared to the current design include:
* `BlobsSidecar` is split into individual `BlobSidecar` containers -
each container is signed individually by the proposer
* the signature is used during gossip validation but later dropped.
* KZG commitment verification is moved out of the gossip pipeline and
instead done before fork choice addition, when both block and sidecars
have arrived
* clients may verify individual blob commitments earlier
* more generally and similar to block verification, gossip propagation
is performed solely based on trivial consistency checks and proposer
signature verification
* by-root blob requests are done per-blob, so as to retain the ability
to fill in blobs one-by-one assuming clients generally receive blobs
from gossip
* by-range blob requests are done per-block, so as to simplify
historical sync
* range and root requests are limited to `128` entries for both blocks
and blobs - practically, the current higher limit of `1024` for blocks
does not get used and keeping the limits consistent simplifies
implementation - with the merge, block sizes have grown significantly
and clients generally fetch smaller chunks.
2023-02-07 09:55:51 +00:00
#### BlobSidecarsByRoot v1
**Protocol ID:** `/eth2/beacon_chain/req/blob_sidecars_by_root/1/`
2022-11-08 18:41:48 +00:00
2023-02-10 10:16:51 +00:00
New in deneb.
2022-11-08 18:41:48 +00:00
Request Content:
Free the blobs
This PR reintroduces and further decouples blocks and blobs in EIP-4844,
so as to improve network and processing performance.
Block and blob processing, for the purpose of gossip validation, are
independent: they can both be propagated and gossip-validated
in parallel - the decoupled design allows 4 important optimizations
(or, if you are so inclined, removes 4 unnecessary pessimizations):
* Blocks and blobs travel on independent meshes allowing for better
parallelization and utilization of high-bandwidth peers
* Re-broadcasting after validation can start earlier allowing more
efficient use of upload bandwidth - blocks for example can be
rebroadcast to peers while blobs are still being downloaded
* bandwidth-reduction techniques such as per-peer deduplication are more
efficient because of the smaller message size
* gossip verification happens independently for blocks and blobs,
allowing better sharing / use of CPU and I/O resources in clients
With growing block sizes and additional blob data to stream, the network
streaming time becomes a dominant factor in propagation times - on a
100mbit line, streaming 1mb to 8 peers takes ~1s - this process is
repeated for each hop in both incoming and outgoing directions.
This design in particular sends each blob on a separate subnet, thus
maximising the potential for parallelisation and providing a natural
path for growing the number of blobs per block should the network be
judged to be able to handle it.
Changes compared to the current design include:
* `BlobsSidecar` is split into individual `BlobSidecar` containers -
each container is signed individually by the proposer
* the signature is used during gossip validation but later dropped.
* KZG commitment verification is moved out of the gossip pipeline and
instead done before fork choice addition, when both block and sidecars
have arrived
* clients may verify individual blob commitments earlier
* more generally and similar to block verification, gossip propagation
is performed solely based on trivial consistency checks and proposer
signature verification
* by-root blob requests are done per-blob, so as to retain the ability
to fill in blobs one-by-one assuming clients generally receive blobs
from gossip
* by-range blob requests are done per-block, so as to simplify
historical sync
* range and root requests are limited to `128` entries for both blocks
and blobs - practically, the current higher limit of `1024` for blocks
does not get used and keeping the limits consistent simplifies
implementation - with the merge, block sizes have grown significantly
and clients generally fetch smaller chunks.
2023-02-07 09:55:51 +00:00
```python
class BlobIdentifier(Container):
block_root: Root
index: uint64
```
2022-11-08 18:41:48 +00:00
```
(
2023-02-10 09:40:43 +00:00
List[BlobIdentifier, MAX_REQUEST_BLOBS_SIDECARS * MAX_BLOBS_PER_BLOCK]
2022-11-08 18:41:48 +00:00
)
```
Response Content:
```
(
2023-02-10 09:40:43 +00:00
List[BlobSidecar, MAX_REQUEST_BLOBS_SIDECARS * MAX_BLOBS_PER_BLOCK]
2022-11-08 18:41:48 +00:00
)
```
Free the blobs
This PR reintroduces and further decouples blocks and blobs in EIP-4844,
so as to improve network and processing performance.
Block and blob processing, for the purpose of gossip validation, are
independent: they can both be propagated and gossip-validated
in parallel - the decoupled design allows 4 important optimizations
(or, if you are so inclined, removes 4 unnecessary pessimizations):
* Blocks and blobs travel on independent meshes allowing for better
parallelization and utilization of high-bandwidth peers
* Re-broadcasting after validation can start earlier allowing more
efficient use of upload bandwidth - blocks for example can be
rebroadcast to peers while blobs are still being downloaded
* bandwidth-reduction techniques such as per-peer deduplication are more
efficient because of the smaller message size
* gossip verification happens independently for blocks and blobs,
allowing better sharing / use of CPU and I/O resources in clients
With growing block sizes and additional blob data to stream, the network
streaming time becomes a dominant factor in propagation times - on a
100mbit line, streaming 1mb to 8 peers takes ~1s - this process is
repeated for each hop in both incoming and outgoing directions.
This design in particular sends each blob on a separate subnet, thus
maximising the potential for parallelisation and providing a natural
path for growing the number of blobs per block should the network be
judged to be able to handle it.
Changes compared to the current design include:
* `BlobsSidecar` is split into individual `BlobSidecar` containers -
each container is signed individually by the proposer
* the signature is used during gossip validation but later dropped.
* KZG commitment verification is moved out of the gossip pipeline and
instead done before fork choice addition, when both block and sidecars
have arrived
* clients may verify individual blob commitments earlier
* more generally and similar to block verification, gossip propagation
is performed solely based on trivial consistency checks and proposer
signature verification
* by-root blob requests are done per-blob, so as to retain the ability
to fill in blobs one-by-one assuming clients generally receive blobs
from gossip
* by-range blob requests are done per-block, so as to simplify
historical sync
* range and root requests are limited to `128` entries for both blocks
and blobs - practically, the current higher limit of `1024` for blocks
does not get used and keeping the limits consistent simplifies
implementation - with the merge, block sizes have grown significantly
and clients generally fetch smaller chunks.
2023-02-07 09:55:51 +00:00
Requests sidecars by block root and index.
The response is a list of `BlobSidecar` whose length is less than or equal to the number of requests.
2023-02-14 12:32:18 +00:00
It may be less in the case that the responding peer is missing blocks or sidecars.
2022-11-08 18:41:48 +00:00
Free the blobs
This PR reintroduces and further decouples blocks and blobs in EIP-4844,
so as to improve network and processing performance.
Block and blob processing, for the purpose of gossip validation, are
independent: they can both be propagated and gossip-validated
in parallel - the decoupled design allows 4 important optimizations
(or, if you are so inclined, removes 4 unnecessary pessimizations):
* Blocks and blobs travel on independent meshes allowing for better
parallelization and utilization of high-bandwidth peers
* Re-broadcasting after validation can start earlier allowing more
efficient use of upload bandwidth - blocks for example can be
rebroadcast to peers while blobs are still being downloaded
* bandwidth-reduction techniques such as per-peer deduplication are more
efficient because of the smaller message size
* gossip verification happens independently for blocks and blobs,
allowing better sharing / use of CPU and I/O resources in clients
With growing block sizes and additional blob data to stream, the network
streaming time becomes a dominant factor in propagation times - on a
100mbit line, streaming 1mb to 8 peers takes ~1s - this process is
repeated for each hop in both incoming and outgoing directions.
This design in particular sends each blob on a separate subnet, thus
maximising the potential for parallelisation and providing a natural
path for growing the number of blobs per block should the network be
judged to be able to handle it.
Changes compared to the current design include:
* `BlobsSidecar` is split into individual `BlobSidecar` containers -
each container is signed individually by the proposer
* the signature is used during gossip validation but later dropped.
* KZG commitment verification is moved out of the gossip pipeline and
instead done before fork choice addition, when both block and sidecars
have arrived
* clients may verify individual blob commitments earlier
* more generally and similar to block verification, gossip propagation
is performed solely based on trivial consistency checks and proposer
signature verification
* by-root blob requests are done per-blob, so as to retain the ability
to fill in blobs one-by-one assuming clients generally receive blobs
from gossip
* by-range blob requests are done per-block, so as to simplify
historical sync
* range and root requests are limited to `128` entries for both blocks
and blobs - practically, the current higher limit of `1024` for blocks
does not get used and keeping the limits consistent simplifies
implementation - with the merge, block sizes have grown significantly
and clients generally fetch smaller chunks.
2023-02-07 09:55:51 +00:00
The response is unsigned, i.e. `BlobSidecar` , as the signature of the beacon block proposer
may not be available beyond the initial distribution via gossip.
2023-02-10 09:40:43 +00:00
No more than `MAX_REQUEST_BLOBS_SIDECARS * MAX_BLOBS_PER_BLOCK` may be requested at a time.
2022-11-08 18:41:48 +00:00
2023-02-10 10:16:51 +00:00
`BlobSidecarsByRoot` is primarily used to recover recent blobs (e.g. when receiving a block with a transaction whose corresponding blob is missing).
2022-11-08 18:41:48 +00:00
The response MUST consist of zero or more `response_chunk` .
Free the blobs
This PR reintroduces and further decouples blocks and blobs in EIP-4844,
so as to improve network and processing performance.
Block and blob processing, for the purpose of gossip validation, are
independent: they can both be propagated and gossip-validated
in parallel - the decoupled design allows 4 important optimizations
(or, if you are so inclined, removes 4 unnecessary pessimizations):
* Blocks and blobs travel on independent meshes allowing for better
parallelization and utilization of high-bandwidth peers
* Re-broadcasting after validation can start earlier allowing more
efficient use of upload bandwidth - blocks for example can be
rebroadcast to peers while blobs are still being downloaded
* bandwidth-reduction techniques such as per-peer deduplication are more
efficient because of the smaller message size
* gossip verification happens independently for blocks and blobs,
allowing better sharing / use of CPU and I/O resources in clients
With growing block sizes and additional blob data to stream, the network
streaming time becomes a dominant factor in propagation times - on a
100mbit line, streaming 1mb to 8 peers takes ~1s - this process is
repeated for each hop in both incoming and outgoing directions.
This design in particular sends each blob on a separate subnet, thus
maximising the potential for parallelisation and providing a natural
path for growing the number of blobs per block should the network be
judged to be able to handle it.
Changes compared to the current design include:
* `BlobsSidecar` is split into individual `BlobSidecar` containers -
each container is signed individually by the proposer
* the signature is used during gossip validation but later dropped.
* KZG commitment verification is moved out of the gossip pipeline and
instead done before fork choice addition, when both block and sidecars
have arrived
* clients may verify individual blob commitments earlier
* more generally and similar to block verification, gossip propagation
is performed solely based on trivial consistency checks and proposer
signature verification
* by-root blob requests are done per-blob, so as to retain the ability
to fill in blobs one-by-one assuming clients generally receive blobs
from gossip
* by-range blob requests are done per-block, so as to simplify
historical sync
* range and root requests are limited to `128` entries for both blocks
and blobs - practically, the current higher limit of `1024` for blocks
does not get used and keeping the limits consistent simplifies
implementation - with the merge, block sizes have grown significantly
and clients generally fetch smaller chunks.
2023-02-07 09:55:51 +00:00
Each _successful_ `response_chunk` MUST contain a single `BlobSidecar` payload.
2022-11-08 18:41:48 +00:00
2023-02-10 09:44:31 +00:00
Clients MUST support requesting sidecars since `minimum_request_epoch` , where `minimum_request_epoch = max(finalized_epoch, current_epoch - MIN_EPOCHS_FOR_BLOBS_SIDECARS_REQUESTS, DENEB_FORK_EPOCH)` . If any root in the request content references a block earlier than `minimum_request_epoch` , peers MAY respond with error code `3: ResourceUnavailable` or not include the blob in the response.
2022-11-08 18:41:48 +00:00
Free the blobs
This PR reintroduces and further decouples blocks and blobs in EIP-4844,
so as to improve network and processing performance.
Block and blob processing, for the purpose of gossip validation, are
independent: they can both be propagated and gossip-validated
in parallel - the decoupled design allows 4 important optimizations
(or, if you are so inclined, removes 4 unnecessary pessimizations):
* Blocks and blobs travel on independent meshes allowing for better
parallelization and utilization of high-bandwidth peers
* Re-broadcasting after validation can start earlier allowing more
efficient use of upload bandwidth - blocks for example can be
rebroadcast to peers while blobs are still being downloaded
* bandwidth-reduction techniques such as per-peer deduplication are more
efficient because of the smaller message size
* gossip verification happens independently for blocks and blobs,
allowing better sharing / use of CPU and I/O resources in clients
With growing block sizes and additional blob data to stream, the network
streaming time becomes a dominant factor in propagation times - on a
100mbit line, streaming 1mb to 8 peers takes ~1s - this process is
repeated for each hop in both incoming and outgoing directions.
This design in particular sends each blob on a separate subnet, thus
maximising the potential for parallelisation and providing a natural
path for growing the number of blobs per block should the network be
judged to be able to handle it.
Changes compared to the current design include:
* `BlobsSidecar` is split into individual `BlobSidecar` containers -
each container is signed individually by the proposer
* the signature is used during gossip validation but later dropped.
* KZG commitment verification is moved out of the gossip pipeline and
instead done before fork choice addition, when both block and sidecars
have arrived
* clients may verify individual blob commitments earlier
* more generally and similar to block verification, gossip propagation
is performed solely based on trivial consistency checks and proposer
signature verification
* by-root blob requests are done per-blob, so as to retain the ability
to fill in blobs one-by-one assuming clients generally receive blobs
from gossip
* by-range blob requests are done per-block, so as to simplify
historical sync
* range and root requests are limited to `128` entries for both blocks
and blobs - practically, the current higher limit of `1024` for blocks
does not get used and keeping the limits consistent simplifies
implementation - with the merge, block sizes have grown significantly
and clients generally fetch smaller chunks.
2023-02-07 09:55:51 +00:00
Clients MUST respond with at least one sidecar, if they have it.
2022-11-08 18:41:48 +00:00
Clients MAY limit the number of blocks and sidecars in the response.
2022-03-10 05:31:11 +00:00
2023-02-10 09:40:43 +00:00
#### BlobSidecarsByRange v1
2022-03-10 05:31:11 +00:00
Free the blobs
This PR reintroduces and further decouples blocks and blobs in EIP-4844,
so as to improve network and processing performance.
Block and blob processing, for the purpose of gossip validation, are
independent: they can both be propagated and gossip-validated
in parallel - the decoupled design allows 4 important optimizations
(or, if you are so inclined, removes 4 unnecessary pessimizations):
* Blocks and blobs travel on independent meshes allowing for better
parallelization and utilization of high-bandwidth peers
* Re-broadcasting after validation can start earlier allowing more
efficient use of upload bandwidth - blocks for example can be
rebroadcast to peers while blobs are still being downloaded
* bandwidth-reduction techniques such as per-peer deduplication are more
efficient because of the smaller message size
* gossip verification happens independently for blocks and blobs,
allowing better sharing / use of CPU and I/O resources in clients
With growing block sizes and additional blob data to stream, the network
streaming time becomes a dominant factor in propagation times - on a
100mbit line, streaming 1mb to 8 peers takes ~1s - this process is
repeated for each hop in both incoming and outgoing directions.
This design in particular sends each blob on a separate subnet, thus
maximising the potential for parallelisation and providing a natural
path for growing the number of blobs per block should the network be
judged to be able to handle it.
Changes compared to the current design include:
* `BlobsSidecar` is split into individual `BlobSidecar` containers -
each container is signed individually by the proposer
* the signature is used during gossip validation but later dropped.
* KZG commitment verification is moved out of the gossip pipeline and
instead done before fork choice addition, when both block and sidecars
have arrived
* clients may verify individual blob commitments earlier
* more generally and similar to block verification, gossip propagation
is performed solely based on trivial consistency checks and proposer
signature verification
* by-root blob requests are done per-blob, so as to retain the ability
to fill in blobs one-by-one assuming clients generally receive blobs
from gossip
* by-range blob requests are done per-block, so as to simplify
historical sync
* range and root requests are limited to `128` entries for both blocks
and blobs - practically, the current higher limit of `1024` for blocks
does not get used and keeping the limits consistent simplifies
implementation - with the merge, block sizes have grown significantly
and clients generally fetch smaller chunks.
2023-02-07 09:55:51 +00:00
**Protocol ID:** `/eth2/beacon_chain/req/blob_sidecars_by_range/1/`
2022-03-10 05:31:11 +00:00
2023-02-10 10:16:51 +00:00
New in deneb.
2022-03-10 05:31:11 +00:00
Request Content:
```
(
start_slot: Slot
count: uint64
)
```
Response Content:
Free the blobs
This PR reintroduces and further decouples blocks and blobs in EIP-4844,
so as to improve network and processing performance.
Block and blob processing, for the purpose of gossip validation, are
independent: they can both be propagated and gossip-validated
in parallel - the decoupled design allows 4 important optimizations
(or, if you are so inclined, removes 4 unnecessary pessimizations):
* Blocks and blobs travel on independent meshes allowing for better
parallelization and utilization of high-bandwidth peers
* Re-broadcasting after validation can start earlier allowing more
efficient use of upload bandwidth - blocks for example can be
rebroadcast to peers while blobs are still being downloaded
* bandwidth-reduction techniques such as per-peer deduplication are more
efficient because of the smaller message size
* gossip verification happens independently for blocks and blobs,
allowing better sharing / use of CPU and I/O resources in clients
With growing block sizes and additional blob data to stream, the network
streaming time becomes a dominant factor in propagation times - on a
100mbit line, streaming 1mb to 8 peers takes ~1s - this process is
repeated for each hop in both incoming and outgoing directions.
This design in particular sends each blob on a separate subnet, thus
maximising the potential for parallelisation and providing a natural
path for growing the number of blobs per block should the network be
judged to be able to handle it.
Changes compared to the current design include:
* `BlobsSidecar` is split into individual `BlobSidecar` containers -
each container is signed individually by the proposer
* the signature is used during gossip validation but later dropped.
* KZG commitment verification is moved out of the gossip pipeline and
instead done before fork choice addition, when both block and sidecars
have arrived
* clients may verify individual blob commitments earlier
* more generally and similar to block verification, gossip propagation
is performed solely based on trivial consistency checks and proposer
signature verification
* by-root blob requests are done per-blob, so as to retain the ability
to fill in blobs one-by-one assuming clients generally receive blobs
from gossip
* by-range blob requests are done per-block, so as to simplify
historical sync
* range and root requests are limited to `128` entries for both blocks
and blobs - practically, the current higher limit of `1024` for blocks
does not get used and keeping the limits consistent simplifies
implementation - with the merge, block sizes have grown significantly
and clients generally fetch smaller chunks.
2023-02-07 09:55:51 +00:00
```python
class BlobSidecars(Container):
block_root: Root
List[BlobSidecar, MAX_BLOBS_PER_BLOCK]
2023-02-10 09:40:43 +00:00
```
Free the blobs
This PR reintroduces and further decouples blocks and blobs in EIP-4844,
so as to improve network and processing performance.
Block and blob processing, for the purpose of gossip validation, are
independent: they can both be propagated and gossip-validated
in parallel - the decoupled design allows 4 important optimizations
(or, if you are so inclined, removes 4 unnecessary pessimizations):
* Blocks and blobs travel on independent meshes allowing for better
parallelization and utilization of high-bandwidth peers
* Re-broadcasting after validation can start earlier allowing more
efficient use of upload bandwidth - blocks for example can be
rebroadcast to peers while blobs are still being downloaded
* bandwidth-reduction techniques such as per-peer deduplication are more
efficient because of the smaller message size
* gossip verification happens independently for blocks and blobs,
allowing better sharing / use of CPU and I/O resources in clients
With growing block sizes and additional blob data to stream, the network
streaming time becomes a dominant factor in propagation times - on a
100mbit line, streaming 1mb to 8 peers takes ~1s - this process is
repeated for each hop in both incoming and outgoing directions.
This design in particular sends each blob on a separate subnet, thus
maximising the potential for parallelisation and providing a natural
path for growing the number of blobs per block should the network be
judged to be able to handle it.
Changes compared to the current design include:
* `BlobsSidecar` is split into individual `BlobSidecar` containers -
each container is signed individually by the proposer
* the signature is used during gossip validation but later dropped.
* KZG commitment verification is moved out of the gossip pipeline and
instead done before fork choice addition, when both block and sidecars
have arrived
* clients may verify individual blob commitments earlier
* more generally and similar to block verification, gossip propagation
is performed solely based on trivial consistency checks and proposer
signature verification
* by-root blob requests are done per-blob, so as to retain the ability
to fill in blobs one-by-one assuming clients generally receive blobs
from gossip
* by-range blob requests are done per-block, so as to simplify
historical sync
* range and root requests are limited to `128` entries for both blocks
and blobs - practically, the current higher limit of `1024` for blocks
does not get used and keeping the limits consistent simplifies
implementation - with the merge, block sizes have grown significantly
and clients generally fetch smaller chunks.
2023-02-07 09:55:51 +00:00
2022-03-10 05:31:11 +00:00
```
(
2023-02-10 09:40:43 +00:00
List[BlobSidecars, MAX_REQUEST_BLOB_SIDECARS]
2022-03-10 05:31:11 +00:00
)
```
Free the blobs
This PR reintroduces and further decouples blocks and blobs in EIP-4844,
so as to improve network and processing performance.
Block and blob processing, for the purpose of gossip validation, are
independent: they can both be propagated and gossip-validated
in parallel - the decoupled design allows 4 important optimizations
(or, if you are so inclined, removes 4 unnecessary pessimizations):
* Blocks and blobs travel on independent meshes allowing for better
parallelization and utilization of high-bandwidth peers
* Re-broadcasting after validation can start earlier allowing more
efficient use of upload bandwidth - blocks for example can be
rebroadcast to peers while blobs are still being downloaded
* bandwidth-reduction techniques such as per-peer deduplication are more
efficient because of the smaller message size
* gossip verification happens independently for blocks and blobs,
allowing better sharing / use of CPU and I/O resources in clients
With growing block sizes and additional blob data to stream, the network
streaming time becomes a dominant factor in propagation times - on a
100mbit line, streaming 1mb to 8 peers takes ~1s - this process is
repeated for each hop in both incoming and outgoing directions.
This design in particular sends each blob on a separate subnet, thus
maximising the potential for parallelisation and providing a natural
path for growing the number of blobs per block should the network be
judged to be able to handle it.
Changes compared to the current design include:
* `BlobsSidecar` is split into individual `BlobSidecar` containers -
each container is signed individually by the proposer
* the signature is used during gossip validation but later dropped.
* KZG commitment verification is moved out of the gossip pipeline and
instead done before fork choice addition, when both block and sidecars
have arrived
* clients may verify individual blob commitments earlier
* more generally and similar to block verification, gossip propagation
is performed solely based on trivial consistency checks and proposer
signature verification
* by-root blob requests are done per-blob, so as to retain the ability
to fill in blobs one-by-one assuming clients generally receive blobs
from gossip
* by-range blob requests are done per-block, so as to simplify
historical sync
* range and root requests are limited to `128` entries for both blocks
and blobs - practically, the current higher limit of `1024` for blocks
does not get used and keeping the limits consistent simplifies
implementation - with the merge, block sizes have grown significantly
and clients generally fetch smaller chunks.
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Requests blob sidecars in the slot range `[start_slot, start_slot + count)` ,
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leading up to the current head block as selected by fork choice.
Free the blobs
This PR reintroduces and further decouples blocks and blobs in EIP-4844,
so as to improve network and processing performance.
Block and blob processing, for the purpose of gossip validation, are
independent: they can both be propagated and gossip-validated
in parallel - the decoupled design allows 4 important optimizations
(or, if you are so inclined, removes 4 unnecessary pessimizations):
* Blocks and blobs travel on independent meshes allowing for better
parallelization and utilization of high-bandwidth peers
* Re-broadcasting after validation can start earlier allowing more
efficient use of upload bandwidth - blocks for example can be
rebroadcast to peers while blobs are still being downloaded
* bandwidth-reduction techniques such as per-peer deduplication are more
efficient because of the smaller message size
* gossip verification happens independently for blocks and blobs,
allowing better sharing / use of CPU and I/O resources in clients
With growing block sizes and additional blob data to stream, the network
streaming time becomes a dominant factor in propagation times - on a
100mbit line, streaming 1mb to 8 peers takes ~1s - this process is
repeated for each hop in both incoming and outgoing directions.
This design in particular sends each blob on a separate subnet, thus
maximising the potential for parallelisation and providing a natural
path for growing the number of blobs per block should the network be
judged to be able to handle it.
Changes compared to the current design include:
* `BlobsSidecar` is split into individual `BlobSidecar` containers -
each container is signed individually by the proposer
* the signature is used during gossip validation but later dropped.
* KZG commitment verification is moved out of the gossip pipeline and
instead done before fork choice addition, when both block and sidecars
have arrived
* clients may verify individual blob commitments earlier
* more generally and similar to block verification, gossip propagation
is performed solely based on trivial consistency checks and proposer
signature verification
* by-root blob requests are done per-blob, so as to retain the ability
to fill in blobs one-by-one assuming clients generally receive blobs
from gossip
* by-range blob requests are done per-block, so as to simplify
historical sync
* range and root requests are limited to `128` entries for both blocks
and blobs - practically, the current higher limit of `1024` for blocks
does not get used and keeping the limits consistent simplifies
implementation - with the merge, block sizes have grown significantly
and clients generally fetch smaller chunks.
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The response is unsigned, i.e. `BlobSidecarsByRange` , as the signature of the beacon block proposer
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may not be available beyond the initial distribution via gossip.
Before consuming the next response chunk, the response reader SHOULD verify the blobs sidecar is well-formatted and
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correct w.r.t. the expected KZG commitments through `validate_blobs_sidecar` .
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`BlobsSidecarsByRange` is primarily used to sync blobs that may have been missed on gossip and to sync within the `MIN_EPOCHS_FOR_BLOBS_SIDECARS_REQUESTS` window.
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The request MUST be encoded as an SSZ-container.
The response MUST consist of zero or more `response_chunk` .
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Each _successful_ `response_chunk` MUST contain a single `BlobsSidecar` payload.
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Clients MUST keep a record of signed blobs sidecars seen on the epoch range
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`[max(current_epoch - MIN_EPOCHS_FOR_BLOBS_SIDECARS_REQUESTS, DENEB_FORK_EPOCH), current_epoch]`
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where `current_epoch` is defined by the current wall-clock time,
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and clients MUST support serving requests of blobs on this range.
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Free the blobs
This PR reintroduces and further decouples blocks and blobs in EIP-4844,
so as to improve network and processing performance.
Block and blob processing, for the purpose of gossip validation, are
independent: they can both be propagated and gossip-validated
in parallel - the decoupled design allows 4 important optimizations
(or, if you are so inclined, removes 4 unnecessary pessimizations):
* Blocks and blobs travel on independent meshes allowing for better
parallelization and utilization of high-bandwidth peers
* Re-broadcasting after validation can start earlier allowing more
efficient use of upload bandwidth - blocks for example can be
rebroadcast to peers while blobs are still being downloaded
* bandwidth-reduction techniques such as per-peer deduplication are more
efficient because of the smaller message size
* gossip verification happens independently for blocks and blobs,
allowing better sharing / use of CPU and I/O resources in clients
With growing block sizes and additional blob data to stream, the network
streaming time becomes a dominant factor in propagation times - on a
100mbit line, streaming 1mb to 8 peers takes ~1s - this process is
repeated for each hop in both incoming and outgoing directions.
This design in particular sends each blob on a separate subnet, thus
maximising the potential for parallelisation and providing a natural
path for growing the number of blobs per block should the network be
judged to be able to handle it.
Changes compared to the current design include:
* `BlobsSidecar` is split into individual `BlobSidecar` containers -
each container is signed individually by the proposer
* the signature is used during gossip validation but later dropped.
* KZG commitment verification is moved out of the gossip pipeline and
instead done before fork choice addition, when both block and sidecars
have arrived
* clients may verify individual blob commitments earlier
* more generally and similar to block verification, gossip propagation
is performed solely based on trivial consistency checks and proposer
signature verification
* by-root blob requests are done per-blob, so as to retain the ability
to fill in blobs one-by-one assuming clients generally receive blobs
from gossip
* by-range blob requests are done per-block, so as to simplify
historical sync
* range and root requests are limited to `128` entries for both blocks
and blobs - practically, the current higher limit of `1024` for blocks
does not get used and keeping the limits consistent simplifies
implementation - with the merge, block sizes have grown significantly
and clients generally fetch smaller chunks.
2023-02-07 09:55:51 +00:00
Peers that are unable to reply to blob sidecar requests within the `MIN_EPOCHS_FOR_BLOBS_SIDECARS_REQUESTS`
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epoch range SHOULD respond with error code `3: ResourceUnavailable` .
Such peers that are unable to successfully reply to this range of requests MAY get descored
or disconnected at any time.
*Note*: The above requirement implies that nodes that start from a recent weak subjectivity checkpoint
MUST backfill the local blobs database to at least epoch `current_epoch - MIN_EPOCHS_FOR_BLOBS_SIDECARS_REQUESTS`
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to be fully compliant with `BlobsSidecarsByRange` requests.
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*Note*: Although clients that bootstrap from a weak subjectivity checkpoint can begin
participating in the networking immediately, other peers MAY
disconnect and/or temporarily ban such an un-synced or semi-synced client.
Clients MUST respond with at least the first blobs sidecar that exists in the range, if they have it,
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and no more than `MAX_REQUEST_BLOCKS_DENEB` sidecars.
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The following blobs sidecars, where they exist, MUST be sent in consecutive order.
Clients MAY limit the number of blobs sidecars in the response.
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An empty `BlobSidecar` is one that does not contain any blobs, but contains non-zero `beacon_block_root` , `beacon_block_slot` and a valid `kzg_aggregated_proof` .
Clients MAY NOT want to consider empty `BlobSidecar` s in rate limiting logic.
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The response MUST contain no more than `count` blobs sidecars.
Clients MUST respond with blobs sidecars from their view of the current fork choice
-- that is, blobs sidecars as included by blocks from the single chain defined by the current head.
Of note, blocks from slots before the finalization MUST lead to the finalized block reported in the `Status` handshake.
Clients MUST respond with blobs sidecars that are consistent from a single chain within the context of the request.
After the initial blobs sidecar, clients MAY stop in the process of responding
if their fork choice changes the view of the chain in the context of the request.
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## Design decision rationale
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### Why are blobs relayed as a sidecar, separate from beacon blocks?
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This "sidecar" design provides forward compatibility for further data increases by black-boxing `is_data_available()` :
with full sharding `is_data_available()` can be replaced by data-availability-sampling (DAS)
thus avoiding all blobs being downloaded by all beacon nodes on the network.
Such sharding design may introduce an updated `BlobsSidecar` to identify the shard,
but does not affect the `BeaconBlock` structure.
