Internet DRAFT - draft-yao-coinrg-generic-framework
draft-yao-coinrg-generic-framework
Computing in the Network Research Group K. Yao
Internet-Draft S. Xu
Intended status: Informational Z. Li
Expires: 14 September 2023 China Mobile
W. Wu
Peking University
13 March 2023
A Generic COIN framework in controlled environments
draft-yao-coinrg-generic-framework-00
Abstract
There have been a lot of academic research and industrial practice in
the area of COIN, but most of them are case-by-case design and
currently they also rely heavily on programmable network devices,
which lacks some generality and scalability, thus will impede the
development of COIN. This document summarizes the computing
primitives/operations/semantics that can be implemented inside the
network, through analysis of different COIN use cases, and proposes a
generic framework of COIN in the controlled environments. Enabling
technologies related to the framework and the standardization
landscape are also analyzed in the document.
Status of This Memo
This Internet-Draft is submitted in full conformance with the
provisions of BCP 78 and BCP 79.
Internet-Drafts are working documents of the Internet Engineering
Task Force (IETF). Note that other groups may also distribute
working documents as Internet-Drafts. The list of current Internet-
Drafts is at https://datatracker.ietf.org/drafts/current/.
Internet-Drafts are draft documents valid for a maximum of six months
and may be updated, replaced, or obsoleted by other documents at any
time. It is inappropriate to use Internet-Drafts as reference
material or to cite them other than as "work in progress."
This Internet-Draft will expire on 14 September 2023.
Copyright Notice
Copyright (c) 2023 IETF Trust and the persons identified as the
document authors. All rights reserved.
Yao, et al. Expires 14 September 2023 [Page 1]
Internet-Draft Computing in the Network Research Group March 2023
This document is subject to BCP 78 and the IETF Trust's Legal
Provisions Relating to IETF Documents (https://trustee.ietf.org/
license-info) in effect on the date of publication of this document.
Please review these documents carefully, as they describe your rights
and restrictions with respect to this document. Code Components
extracted from this document must include Revised BSD License text as
described in Section 4.e of the Trust Legal Provisions and are
provided without warranty as described in the Revised BSD License.
Table of Contents
1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . 2
2. Conventions Used in This Document . . . . . . . . . . . . . . 3
2.1. Terminology . . . . . . . . . . . . . . . . . . . . . . . 3
2.2. Requirements Language . . . . . . . . . . . . . . . . . . 3
3. Generic Framework . . . . . . . . . . . . . . . . . . . . . . 3
4. Enabling Technologies . . . . . . . . . . . . . . . . . . . . 5
4.1. The Scheduling Layer . . . . . . . . . . . . . . . . . . 5
4.2. The Control Layer . . . . . . . . . . . . . . . . . . . . 5
4.3. The Infrastructure Layer . . . . . . . . . . . . . . . . 5
5. Research challenges and other considerations . . . . . . . . 6
6. Security Considerations . . . . . . . . . . . . . . . . . . . 7
7. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 7
8. Normative References . . . . . . . . . . . . . . . . . . . . 7
Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . 7
1. Introduction
Programmable network devices(PNDs) including programmable switches
and SmartNICs have inspired a lot of research work in the area of
COIN. Like In-band Network Telemetry(INT), Network functions
offloading(LBs, Firewalls), etc. However, technically, we argue that
these use cases are not strictly “computing” in the network, since
they are hardware implementation of network functions which
traditionally implemented in servers so as to accelerate or enhance
these network functions. The “network” in COIN is also ambiguous.
Narrowly, it refers to network devices like PNDs, but broadly, it
refers to network elements in different contexts. In edge computing
or fog computing, these network elements refer to ubiquitous
heterogeneous edge devices, but in controlled environments like data
centers, network elements refer to normal network devices. And in
this draft, we just limit the scope of the discussion inside the
controlled environment, which is consistent with most of the existing
work.
To make the work in COIN move further, there is a need to reach a
consensus on the definition of COIN. Despite there is an ongoing
draft about the terminology of COIN in the group, we want to share
Yao, et al. Expires 14 September 2023 [Page 2]
Internet-Draft Computing in the Network Research Group March 2023
our thoughts. Computing in the network is “to offload application-
specific functions to network elements, so as to accelerate
applications”. These application-specific functions are described by
series of computing primitives/operations/semantics that could be
supported by network elements, and they explain about what to
“compute” in the network. A very illustrative example is In-network
Aggregation(INA) for distributed machine learning model training.
The aggregation operation is implemented in network devices, which
could accelerate the entire model training process.A lot of research
have investigated what kind of computing primitives can be offloaded
to network devices, but there still lack a systematic summarization
of these application-specific primitives. We think that application-
specific functions can be generalized to be several types of
computing primitives which could be further standardized, thus COIN
will not depend on PNDs for implementation, but normal network
devices that support these general primitives could take the work.
Further, current research on how COIN could accelerate applications
usually depend on a case-by-case hardware software co-design scheme,
which lacks generality and scalability for the development of COIN.
There is a need to design a generic framework of COIN, for one thing,
to make COIN a common capability of the network, for another, to
lower the application development barriers.
Based on the analysis above, this document classifies several kinds
of computing primitives which could be standardized, and proposes a
generic framework of COIN, which can be scaled and promoted in the
controlled environment.
2. Conventions Used in This Document
2.1. Terminology
PND Programmable Network Device
2.2. Requirements Language
The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT",
"SHOULD", "SHOULD NOT", "RECOMMENDED", "NOT RECOMMENDED", "MAY", and
"OPTIONAL" in this document are to be interpreted as described in BCP
14[RFC2119][RFC8174] when, and only when, they appear in all
capitals, as shown here.
3. Generic Framework
The generic COIN framework contains three logical layers: Scheduling
layer(S), Control layer(C), and Infrastructure layer(I).
Yao, et al. Expires 14 September 2023 [Page 3]
Internet-Draft Computing in the Network Research Group March 2023
+---------------------------------------------------------------------+
| Scheduling Layer |
| +---------------------------------------------------------------+ |
| | Scheduler | |
| | | |
| | Resource (Host and COIN） | |
| | Job Decomposition (Task Scheduling Policy ) | |
| +---------------------------------------------------------------+ |
+---------------------------------------------------------------------+
|Host Task |COIN Task
+---------------------------------------------------------------------+
| Control Layer | | |
| | | |
| +----------------v------------+ +---------------v-------------+ |
| | Host Controller | | COIN Controller | |
| | （ optional） -----> | |
| | Collaboration COIN Task Installation | |
| | Host Task Installation | | Routing | |
| | End-Network Collaboration <-----+ End-Network Collaboration | |
| +-----------------------------+ +-----------------------------+ |
+---------------------------------------------------------------------+
| Host Management | Device Management
| Host Task Control | COIN Task Control
| |
+-----------------+---------------------------------------------------+
| Infrastructure Layer | |
| | | |
| +------------v---------+ +-----------v----------------+ |
| | Host | | Network Device | |
| | | | | |
| +---------------- -----+ +----------------------------+ |
+---------------------------------------------------------------------+
Figure 1: Figure 1: Generic COIN Framework
The scheduling layer (S) decomposes a job into host tasks and COIN
tasks according to the host and COIN resources and scheduling policy.
These tasks are then distributed to the control layer.
The control layer (C) is divided into host controller and COIN
controller, both of them can be centralized or distributed. Host
Controller is optional, which is deployed on demand according to the
application scenario. A host controller is mainly responsible for
host task deployment and control. The COIN controller is mainly
responsible for network management, COIN task deployment and control,
and routing. The host controller and the COIN controller are
combined to realize the end-network cooperation.
Yao, et al. Expires 14 September 2023 [Page 4]
Internet-Draft Computing in the Network Research Group March 2023
The infrastructure layer (I) includes the host and network equipment,
including the relevant routing protocols and reliability protocols to
realize COIN.
4. Enabling Technologies
4.1. The Scheduling Layer
Task decomposition is the first step to achieve end-network
collaborative in-network computing. Through appropriate scheduling
policy, reasonable resource allocation can be achieved and better
task performance can be achieved. With the addition of in-network
computing technology, it is necessary to consider not only the host
resources, but also the in-network computing resources.
4.2. The Control Layer
End-network collaborative control realized by the host controller and
the COIN controller.
Network side:
* Network equipment management, including network equipment status,
load condition, network equipment computing capacity and resource,
etc.
* Network topology management, including network topology update,
link status monitoring, etc.
* Routing, selecting an optimal path for in-network computing and
forwarding.
Host side:
* Cooperate with the host application to do the COIN processing,
including completing the overall calculation task with the network
side, and reliability control.
4.3. The Infrastructure Layer
Network equipment implements the standard COIN primitive.
A set of unified COIN primitives makes COIN more easier to achieve
docking and promotion. Some research work
[NetRPC][Netcompute]summarize common COIN primitives and data
structures. We refer to these research work and choose some major
COIN primitives out of these work. ValStr_Agg is used in
applications like distributed machine learning training, Asyn_Val_Agg
Yao, et al. Expires 14 September 2023 [Page 5]
Internet-Draft Computing in the Network Research Group March 2023
is used in big data analysis applications where map-reduce is needed.
K-V is used for caching, and consensus is used for synchronization
within distributed systems. Heterogeneous network devices can have
different internal implementations of the same COIN primitives, but
the services provided externally need to be unified. There is a need
to standardize these COIN primitives for generic use cases. Of
course, due to equipment differences, there may be differences in
calculation accuracy for some primitives. These differences need to
be considered in task decomposition and routing.
+------------+--------------+-------------------------------------+
| Type |Data Structure| Primitives |
+------------------------------------------------------------------
| ValStr_Agg | Array | Map.get, Map.add, Map.clear |
+------------------------------------------------------------------
|Asyn_Val_Agg| Map | Map.get, Map.add, Stream.modify |
+------------------------------------------------------------------
| K-V | Map | Map.get, Map.add |
+------------------------------------------------------------------
| consensus | Integer | Map.get, Map.add, Map.clear |
+------------+--------------+-------------------------------------+
Figure 2: Figure 2: COIN Primitives
COIN transformation of application program on host side.
Network cannot guarantee that the computing task can be completed
during each transmission process, so the host side applications need
to be COIN aware and be able to flexibly process the data that has
been in-network processed or not.
5. Research challenges and other considerations
* End and network collaboration. Due to the limited resources within
network devices, there is a need to design some fallback mechanisms
when tasks cannot be fully accomplished within the network, and they
should be finished at the end devices. Relative algorithms,
protocols should be considered for implementation.
* COIN reliability and correctness. On the premise that tasks can be
offloaded to network devices for computing, the correctness and
reliability of the work should be considered. There should be some
mechanisms designed to maintain that the COIN results is consistent
with that when tasks are fully accomplished at end devices. Besides,
reliable data transmission in COIN should be elaborately designed,
since many applications have very strict QoS requirements.
Yao, et al. Expires 14 September 2023 [Page 6]
Internet-Draft Computing in the Network Research Group March 2023
6. Security Considerations
TBD.
7. IANA Considerations
TBD.
8. Normative References
[Netcompute]
Dan R. K. Ports, Jacob Nelson, "When Should The Network Be
The Computer?", May 2019,
<https://doi.org/10.1145/3317550.3321439>.
[NetRPC] Zhao, B., Wu, W., & Xu, W., "NetRPC: Enabling In-Network
Computation in Remote Procedure Calls", December 2022,
<https://doi.org/10.48550/arXiv.2212.08362>.
[RFC2119] Bradner, S., "Key words for use in RFCs to Indicate
Requirement Levels", BCP 14, RFC 2119,
DOI 10.17487/RFC2119, March 1997,
<https://www.rfc-editor.org/info/rfc2119>.
[RFC8174] Leiba, B., "Ambiguity of Uppercase vs Lowercase in RFC
2119 Key Words", BCP 14, RFC 8174, DOI 10.17487/RFC8174,
May 2017, <https://www.rfc-editor.org/info/rfc8174>.
Authors' Addresses
Kehan Yao
China Mobile
Beijing
100053
China
Email: yaokehan@chinamobile.com
Shiping Xu
China Mobile
Beijing
100053
China
Email: xushiping@chinamobile.com
Yao, et al. Expires 14 September 2023 [Page 7]
Internet-Draft Computing in the Network Research Group March 2023
Zhiqiang Li
China Mobile
Beijing
100053
China
Email: lizhiqiangyjy@chinamobile.com
Wenfei Wu
Peking University
Beijing
100871
China
Email: wenfeiwu@pku.edu.cn
Yao, et al. Expires 14 September 2023 [Page 8]
