none L. Qiang
Internet-Draft Huawei
Intended status: Informational A. Galis
Expires: March 29, 2018 University College London
L. Geng
China Mobile
K. Makhijani
Huawei
P. Martinez-Julia
NICT
H. Flinck
Nokia
September 25, 2017
Technology Independent Information Model for Network Slicing
draft-qiang-coms-netslicing-information-model-00
Abstract
This document provides a technology independent information model for
transport network slicing.
Status of This Memo
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Table of Contents
1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . 2
2. Terminology . . . . . . . . . . . . . . . . . . . . . . . . . 3
3. Network Slice Tree Structure . . . . . . . . . . . . . . . . 3
3.1. atomic-component . . . . . . . . . . . . . . . . . . . . 5
3.1.1. connectivity-cateogry . . . . . . . . . . . . . . . . 6
3.1.2. storage-cateogry . . . . . . . . . . . . . . . . . . 7
3.1.3. compute-categoty . . . . . . . . . . . . . . . . . . 8
3.2. predefined-function-block . . . . . . . . . . . . . . . . 8
3.3. global-attributes . . . . . . . . . . . . . . . . . . . . 8
4. Opeartions . . . . . . . . . . . . . . . . . . . . . . . . . 10
5. Security Considerations . . . . . . . . . . . . . . . . . . . 11
6. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 11
7. Acknowledgements . . . . . . . . . . . . . . . . . . . . . . 11
8. Informative References [TBD] . . . . . . . . . . . . . . . . 11
Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . 11
1. Introduction
Considering the business logic of network slicing as shown in Fig.
Figure 1. At the top layer, tenants describe the service that they
want through a service model, and this service model dose not bind to
any specific implementation technology. At the bottom layer,
multiple technologies are available to be used to support the network
slicing service. Between the common service model and lots of
available implementation technologies, there is a gap which needs a
technology independent information model. During the implementation
process, the most appropriate technology will be selected according
to the SLA, and the management/operations on the information model
also will be translated into the language understood by the select
technology (or directly translated into a set of network parameters
configurations).
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Service Model
Tenant<---------->Network Slicing Service Provider
^
|
|
|Management/Operations
+---------------------v-----------------------+
| Technology Independent NS Information Model |
+---------------------^-----------------------+
|Mapping to Specific Technology
|
|
+----------+-----------+------------+
| | | |
| | | | NS-Oriented Extension in
| | | | Each Specific Technology
| | | |
+---v--+ +--v---+ +--v---+ +---v--+ Available
| ACTN | |DetNet| | VPN | | SR | ... Implementation
+------+ +------+ +------+ +------+ Technologies
Figure 1: Technology Independent NS Information Model
2. Terminology
The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT",
"SHOULD", "SHOULD NOT", "RECOMMENDED", "MAY", and "OPTIONAL" in this
document are to be interpreted as described in [RFC2119].
Other network slicing related words used in this document are
interpreted as description in [COMS-PS].
Yang language is used to represent the transport network slice
information model.
3. Network Slice Tree Structure
Following is the tree structure of network slice.
module: ietf-coms-information-model
+--rw network-slice
+--rw atomic-component
| +--rw connectivity-category
| | +--rw node-list
| | | +--rw node*
| | | +--rw node-id string
| | | +--rw location? string
| | | +--rw port* [port-id]
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| | | | +--rw port-id string
| | | | +--rw port-rate? int32
| | | | +--rw packet-loss-probability? uint8
| | | | +--rw packet-loss-threshold? unit8
| | | | +--rw received-packets? int32
| | | | +--rw sent-packets? int32
| | | +--rw forwarding-policy
| | | +--rw match? string
| | | +--rw action? string
| | | +--rw priority? string
| | | +--rw counter? int64
| | +--rw link-list
| | +--rw link* [link-id]
| | +--rw link-id string
| | +--rw src-node
| | | +--rw node-id string
| | +--rw src-port
| | | +--rw port-id string
| | +--rw dst-node
| | | +--rw node-id string
| | +--rw src-port
| | | +--rw port-id string
| | +--rw link-bandwidth-agreement? string
| | +--rw link-throughput? string
| | +--rw link-throughput-threshold? string
| | +--rw link-latency-agreement? string
| | +--rw link-latency? string
| | +--rw link-jitter-agreement? string
| | +--rw link-jitter? string
| | +--rw link-jitter-threshold? string
| | +--rw physical-path-restriction
| | +--rw mandatory-physical-device*
| | +--rw exclusive-physical-device*
| +--rw storage-category
| | +--rw storage-unit* [storage-unit-id]
| | +--rw storage-unit-id string
| | +--rw size? int64
| | +--rw ingress-rate? string
| | +--rw egress-rate? string
| | +--rw read-write-mode? enumeration
| | +--rw access-mode? enumeration
| | +--rw redundancy? boolean
| | +--rw location? string
| +--rw compute-category
| +--rw compute-unit* [compute-unit-id]
| +--rw compute-unit-id string
| +--rw alu-number? int8
| +--rw speed? string
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| +--rw cache-size? string
| +--rw access-mode? enumeration
| +--rw location? string
+--rw predefined-function-block
| +--rw sdn-controller
| | +--rw ActiveOF
| | | +--rw OFServer* [ServerName]
| | | +--rw ServerName string
| | | +--rw IPAddress? IPAddressType
| | | +--rw Port? PortType
| | +--rw PassiveOF
| | +--rw OFPort? PortType
| +--rw firewall
| +--rw vswitch
| +--rw load-balancer
+--rw global-attributes
+--rw qos-agreement
| +--rw max-latency? string
| +--rw min-bandwidth? string
| +--rw max-jitter? string
| +--rw max-packet-loss-probability? uint8
+--rw qos-monitored-result
| +--rw slice-level-latency? string
| +--rw slice-level-bandwidth? string
| +--rw slice-level-jitter? string
| +--rw slice-level-packet-loss-probability? uint8
+--rw topology-requirement
| +--rw node-list
| +--rw link-list
+--rw reliability-level? unit8
+--rw resource-reservation-level? unit8
+--rw availability? string
+--rw availability-threshold? string
+--rw access-control
+--rw match? string
+--rw action? string
+--rw priority? string
+--rw counter? int64
3.1. atomic-component
The atomic-component refers to the basic resources to construct a
network slice. According to the different capabilities provided,
atomic-component could be further divided into three cateogries:
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o connectivity-cateogry: resources to provide connectivity, include
nodes and links.
o storage-cateogry: resources to provide storage, such as RAM, ROM,
etc.
o compute-categoty: resource to provide compute, such as CPU, GPU,
etc.
Different cateogries of atomic-components could exist independently,
they also can be bound together when necessary. For example, bind a
storage unit to a connectivity node.
3.1.1. connectivity-cateogry
3.1.1.1. node
For easy going, some attributes of node are explained as follows:
location: a string which indicates a geographical area, the node must
be mapped to the physical device(s) inside this indicated
geographical area.
forwarding policy: could be the routing table or flow table or other
information indicates the forwarding policy of this node.
port rate: the packet forwarding capability of a port for this node
in the unit of pps (packet per second).
packet-loss-probability: a statistical value which reflects the
probability of packet loss.
packet-loss-threshold: a threshold of the packet loss probability.
If the value of packet-loss-probability is larger than packet-loss-
threshold, should actively notify the management system.
received-packets: a statistical value which reflects the number of
received packets in a period of time.
sent-packets: a statistical value which reflects the number of sent
packets in a period of time.
3.1.1.2. link
Some attributes of link are explained as follows:
src-node: the source node the link.
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src-port: the port of the source node.
dst-node: the destination node of the link.
dst-port: the port of the destination node.
link-bandwidth-agreement: specify the bandwidth requirement for this
link. If this parameter does not be set specifically, then the link
will be constructed according to the default bandwidth calculated by
algorithm.
link-throughput: the current throughput of this link.
link-throughput-threshold: a threshold for link throughput. If the
value of link-throughput is smaller than link-throughput-threshold,
should actively notify the management system.
link-latency-agreement: specify the latency requirement for this
link. If this parameter does not be set specifically, then the link
will be constructed according to the default latency calculated by
algorithm.
link-latency: the current latency of this link.
link-jitter-agreement: specify the jitter requirement for this link.
If this parameter does not be set specifically, then the link will be
constructed according to the default jitter calculated by algorithm.
link-jitter: the current jitter of this link.
link-jitter-threshold: a threshold for link jitter. If the value of
link-jitter is larger than link-jitter-threshold, should actively
notify the management system.
mandatory-physical-device*: a list of physical devices that must be
passed by the mapped physical path of this link.
exclusive-physical-device*: a list of physical devices that cannot be
passed by the mapped physical path of this link.
3.1.2. storage-cateogry
read-write-mode: there are three options include read only, write
only, and read & write.
access-mode: two options include shared or dedicated.
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redundancy: bool value indicate wheter the storage unit has back-up
or not.
location: the location of the storage unite, could be used to bind to
a connectivity node.
3.1.3. compute-categoty
alu-number: the number of arithmetic logic unit
access-mode: two options include shared or dedicated.
location: the location of the storage unite, could be used to bind to
a connectivity node.
3.2. predefined-function-block
Some typical features could be packaged into function blocks in
advance, such as SDN controller, firewall, vSwitch, load balancer,
etc.
3.3. global-attributes
The global-attributes refers to a set of attributes in the whole
network slice level. Some explanations are provided as follows for
easy going:
qos-agreement: spcify some global QoS metrics of a whole network
slice.
qos-monitored-result: the monitored results of the global QoS
metrics.
topology-requirement: should be able to support a variety of topology
construction methods, such as: 1) given the complete topology
information (i.e., the whole nodes and links lists); 2) only given
some key information (e.g., edge nodes, converge nodes).
reliability-level: the ability of a network slice to be in a stable
state. In this document, the main method to achieve reliability is
"backup". If necessary, other methods also can be extended based on
the current definition. The detailed definition of Reliability_Level
is provided in Table 1.
resource-reservation-level: classify different resource reservation
levels of a network slice. This attribute is related to the slice
isolation but is not strictly bound. The detailed definition is
provided in Table 2.
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availability: a statistical value which reflects the probability for
a network slice instance to work with expected SLA in a period of
time (e.g., 99.999% of time).
availability-threshold: a threshold of the availability. If the
value of Availability is smaller than Availability_Threshold, should
actively notify the management system.
access-control: llustrate each role can take what kind of operations
on the network slice.
+=======+=====================================+========================+
| | | |
| Value | Explanation | Note |
| | | |
+=======+=====================================+========================+
| | | |
| 0 | No specific reliability requirement | The lowest reliability |
| | | level |
+-------+-------------------------------------+------------------------+
| | | |
| 1 | Each path has a backup path | Path reliability |
| | | |
+-------+-------------------------------------+------------------------+
| | | |
| 2 | Each node/link has a backup node/ | Logical resource |
| | link | reliability |
+-------+-------------------------------------+------------------------+
| | | |
| 3 | Each node/link has a backup node/ | Physical resource |
| | link, and the primary and backup | reliability |
| | nodes/links must be mapped to | |
| | different physical devices/paths | |
| | (the mapped two physical paths | |
| | couldn't have any shared device) | |
| | | |
+=======+=====================================+========================+
Table 1: Explanation of reliability-level
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+=======+=====================================+========================+
| | | |
| Value | Explanation | Note |
| | | |
+=======+=====================================+========================+
| | | |
| 0 | No specific resource reservation | The lowest resource |
| | requirement | reservation level, the |
| | | network slice instance |
| | | will share and compete |
| | | for resource with other|
| | | network slice instances|
| | | |
+-------+-------------------------------------+------------------------+
| | | |
| 1 | A certain of resource reservation, | Shared and |
| | the free reserved resources could be| non-preemptive |
| | used by other slice instances, and | |
| | unable to be retrieved if other | |
| | slic instances are using them | |
| | | |
+-------+-------------------------------------+------------------------+
| | | |
| 2 | More stringent resource reservation,| Shared and preemptive |
| | the free reserved resources could be| |
| | used by other slice instances, and | |
| | will be retrieved if the network | |
| | slice needs them | |
| | | |
+-------+-------------------------------------+------------------------+
| | | |
| 3 | The reserved resources couldn't be | The highest resource |
| | used by other slice instances, even | reservation level, |
| | if these resources are free | exclusive |
| | | |
+=======+=====================================+========================+
Table 2: Explanation of resource-reservation-level
4. Opeartions
The defined information model should be able to support the following
operations on network slices. Except for support the operations on a
complete network slice, each element insides a network slice also
should be able to be operated specifically.
o construct: construct a network slicee
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o delete: delete a network slice
o modify: modify a constructed network slice
o set_element_value: set the value of an indicated element in a
network slice
o get_element_value: get the value of an indicated element in a
network slice
o monitor: monitor the status of a network slice
o enable_report: enable the active report to the subscribes/
management system when the monitored status changes beyond
expectation
5. Security Considerations
TBD
6. IANA Considerations
There is no IANA action required by this document.
7. Acknowledgements
TBD
8. Informative References [TBD]
[COMS-PS] "NS Framework", <https://www.ietf.org/id/
draft-geng-coms-problem-statement-00.txt>.
[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>.
Authors' Addresses
Li Qiang
Huawei
Email: qiangli3@huawei.com
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Alex Galis
University College London
Email: a.galis@ucl.ac.uk
Liang Geng
China Mobile
Email: gengliang@chinamobile.com
Kiran Makhijani
Huawei
Email: Kiran.Makhijani@huawei.com
Pedro Martinez-Julia
NICT
Email: pedro@nict.go.jp
Hannu Flinck
Nokia
Email: hannu.flinck@nokia.com
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