| Internet Engineering Task Force (IETF) | M-K. Shin |
| Internet-Draft | ETRI |
| Intended status: Informational | M-J. Choi |
| Expires: October 6, 2016 | KNU |
| S. Lee | |
| ETRI | |
| April 4, 2016 |
Yang Data Model for Service Function Chaining Control Plane
draft-shin-sfc-control-plane-yang-01
This document defines Yang data model for control plane management of service function chaining based on [I-D.ietf-sfc-control-plane], which describes components and requirements of SFC control plane.
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Service Function Chaining (SFC) consists of SFC data plane and control plane from the aspect of architecture [I-D.ietf-sfc-architecture]. The document [I-D.ietf-sfc-control-plane] describes requirements for delivering information between SFC control elements and SFC functional elements. By capturing the information conveyed via a set of control interfaces in [I-D.ietf-sfc-control-plane], this document defines Yang data model of management operations performed in a SFC control plane. Note that the base Yang data model for the SFC data plane is already covered in [I-D.penno-sfc-yang].
This document uses the following terms and most of them were reproduced from [I-D.ietf-sfc-architecture] and [I-D.ietf-sfc-control-plane].
Ahead to defining separate sub-modules, overall module structure for the management of SFC control plane is examined. The overall modules consist of 8 sub-modules (groups). The overall module is devised on the basis of the requirements for conveying information between SFC control elements and SFC functional elements described in the document [I-D.ietf-sfc-control-plane].
Module: SFC-control-planes
This section covers general considerations for managing SFC control plane. The considerations are classified into topology, connectivity, performance, traffic classification, load balancing, and event handling.
First, topology discovery or maintenance is necessary in order to monitor whole or parts of SFP or SFC. Various topologies such as point-to-point and multi-points should be supported. Also, in order to show connectivity topology, the naming mechanism must be considered.
Second, a mechanism of checking connectivity to examine that the services of the given SF execute well or not. This is related to SFP maintenance and optimization.
Also, in order to support path optimization, the performance monitoring is necessary. Basically, the checking of availability and status of services included in SFC needs to be supported. Specifically, statistical data such as packet rates, bandwidth, CPU usage, etc., in accordance with SFP and SFC must be provided for path optimization and load balancing.
Next, traffic classification, reclassification and forwarding must be provided in SF level. This mechanism is performed based on policies.
In order to minimize the effects from faults, the load balancing or load sharing needs to be provided. The load balancing among multiple instances of the same SF. Fault handling, and event handling mechanism should be supported.
Finally, historical data of performance and faults must be stored in order to reliable SFC services.
<CODE BEGINS> file "sfc-control-planes@2015-10-15.yang"
module sfc-control-planes {
namespace "urn:etri:params:xml:ns:yang:sfc-cp";
prefix sfc-cp;
include path-maintenance {
revision-date 2015-10-15;
}
include path-optimization {
revision-date 2015-10-15;
}
include load-balancing {
revision-date 2015-10-15;
}
include sfc-topology {
revision-date 2015-10-15;
}
include policy {
revision-date 2015-10-15;
}
include history {
revision-date 2015-10-15;
}
include fault-handling {
revision-date 2015-10-15;
}
include event {
revision-date 2015-10-15;
}
organization "ETRI.";
contact
"M-K. Shin mkshin@etri.re.kr
M-J Choi mjchoi@kangwon.ac.kr";
description
"This Module define the management information of
the control plane as a total of nine modules.";
revision 2015-10-15{
reference
"draft-shin-sfc-control-plane-yang-00 -
Yang Data Model for Service Function Chaining Control Plane";
}
}
<CODE ENDS>
This module checks the aliveness of a SFP. This receives SFP name and returns aliveness result which is true or false value.
<CODE BEGINS> file "path-maintenance@2015-10-15.yang"
submodule path-maintenance {
belongs-to sfc-control-planes {
prefix sfc-control-planes;
}
organization "ETRI.";
contact
"M-K. Shin mkshin@etri.re.kr
M-J Choi mjchoi@kangwon.ac.kr";
description
"This module checks the aliveness of a SFP.
This receive SFP name and returns aliveness
result which is true or false value.";
revision 2015-10-15{
reference
"draft-shin-sfc-control-plane-yang-00 -
Yang Data Model for Service Function Chaining Control Plane";
}
container path-maintenance {
description
"This container checks the aliveness of a SFP.
This receive SFP name and returns aliveness result
which is true or false value.";
leaf sfp-name {
type string;
description
"The name of service function path.";
}
leaf aliveness-of-sfp {
type boolean;
description
"Aliveness flag of the service function.";
}
}
rpc check-path-aliveness {
description "Check a path aliveness.";
input {
leaf sfc-name {
type string;
description
"The name of service function path.";
}
}
output {
leaf Aliveness {
type boolean;
description
"Aliveness flag of the service function.";
}
}
}
}
<CODE ENDS>
This module constructs and maintains a SFP with a low stretch considering the topological locations and properties (e.g., latency, bandwidth) of SFI
<CODE BEGINS> file "path-optimization@2015-10-15.yang"
submodule path-optimization {
belongs-to sfc-control-planes {
prefix sfc-po;
}
organization "ETRI.";
contact
"M-K. Shin mkshin@etri.re.kr
M-J Choi mjchoi@kangwon.ac.kr";
description
"This module constructs and maintains a SFP with a low stretch
considering the topological locations and properties (e.g.,
latency, bandwidth) of SF.";
revision 2015-10-15 {
reference
"draft-shin-sfc-control-plane-yang-00 -
Yang Data Model for Service Function Chaining Control Plane";
}
container path-optimization {
description
"This container constructs and maintains a SFP with
a low stretch considering the topological locations and
properties (e.g., latency, bandwidth) of SF.";
leaf sfp-name {
type string;
description
"The name of service function path to be changed for
optimization.";
}
leaf optimized-sfp {
type string;
description
"The name of optimized service function path.";
}
leaf sfp-availability {
type boolean;
description
"The availability of the optimized service function path:
true or false.";
}
leaf load-status {
type uint8;
description
"A percentage value of load status.";
}
}
rpc find-optimized-sfp {
description
"Find an optimized service function path.";
input {
leaf sfp-name {
type string;
description
"The name of service function path to be changed for
optimization.";
}
}
output {
leaf optimized-sfp {
type string;
description
"The name of optimized service function path.";
}
leaf sfp-availability {
type string;
description
"The availability of the optimized service function path:
true or false.";
}
}
}
}
<CODE ENDS>
This module constructs and maintains SFPs to localize the traffic in the network considering load and administrative domain of SFIs.
<CODE BEGINS> file "load-balancing@2015-10-15.yang"
submodule load-balancing {
belongs-to sfc-control-planes{
prefix sfc-lb;
}
organization "ETRI.";
contact
"M-K. Shin mkshin@etri.re.kr
M-J Choi mjchoi@kangwon.ac.kr";
description
"This module constructs and maintains SFPs to localize the
traffic in the network considering load and administrative
domain of SFIs.";
revision 2015-10-15 {
reference
"draft-shin-sfc-control-plane-yang-00 -
Yang Data Model for Service Function Chaining Control Plane";
}
container load-balancing {
description
"This container constructs and maintains SFPs
to localize the traffic in the network considering load
and administrative domain of SFIs.";
leaf load-type {
type enumeration {
enum traffic{
description
"Traffic";
}
enum cpu{
description
"CPU";
}
enum memory{
description
"Memory";
}
}
description
"A resource type for load balancing.";
}
leaf source-sfp-name {
type string;
description
"The name of service function path with heavy load.";
}
leaf target-sfp-name {
type string;
description
"Another name of service function path for load
distribution.";
}
}
rpc perform-load-balance {
description
"Perform a load balancing.";
input {
leaf load-type {
type enumeration {
enum traffic{
description
"Traffic";
}
enum cpu{
description
"CPU";
}
enum memory{
description
"Memory";
}
}
description
"A resource type for load balancing.";
}
leaf source-sfp-name {
type string;
description
"The name of service function path with heavy load.";
}
}
output {
leaf target-sfp-name {
type string;
description
"Another name of service function path for load
distribution.";
}
}
}
}
<CODE ENDS>
This module shows the connectivity map of currently working SFCs, SFPs and SFIs.
<CODE BEGINS> file "sfc-topology@2015-10-15.yang"
submodule sfc-topology {
belongs-to sfc-control-planes {
prefix sfc-st;
}
organization "ETRI.";
contact
"M-K. Shin mkshin@etri.re.kr
M-J Choi mjchoi@kangwon.ac.kr";
description
"This module shows the connectivity map of currently working
SFCs, SFPs and SFIs.";
revision 2015-10-15 {
reference
"draft-shin-sfc-control-plane-yang-00 -
Yang Data Model for Service Function Chaining Control Plane";
}
container sfc-topology {
description
"This container shows the connectivity map of
currently working SFCs, SFPs and SFIs. ";
leaf name {
type string;
description
"The name of service function chain or service function
path or service function instances.";
}
list lists-of-sf-node {
key name;
description
"A list of service functions that compose the service
chain.";
leaf name {
type string;
description
"A list of service functions that compose the service
chain.";
}
leaf order {
type uint8;
description
"The order of the service functions.";
}
}
}
rpc show-sfc-topology {
description
"Display the topology of service function chain.";
input {
leaf sfc-name {
type string;
description
"The name of service function chain.";
}
}
output {
list lists-of-sf-node {
key name;
description
"A list of service functions that compose the service
chain.";
leaf name {
type string;
description
"A list of service functions that compose the service
chain.";
}
leaf order {
type uint8;
description
"The order of the service functions.";
}
}
}
}
}
<CODE ENDS>
Policies are used to bind an incoming flow to an appropriate SFP.
<CODE BEGINS> file "policy@2015-10-15.yang"
submodule policy {
belongs-to sfc-control-planes {
prefix sfc-p;
}
organization "ETRI.";
contact
"M-K. Shin mkshin@etri.re.kr
M-J Choi mjchoi@kangwon.ac.kr";
description
"Policies are used to bind an incoming flow to an appropriate
SFP.";
revision 2015-10-15 {
reference
"draft-shin-sfc-control-plane-yang-00 -
Yang Data Model for Service Function Chaining Control Plane";
}
container classification-policy-table {
description
"One SFC is selected by the classification function according to
the defined policy. The classification means service profile
matching of traffic flows for identification of appropriate
outbound forwarding actions.";
list classification-policy-table {
key flow-identifier;
description
"To classify the flow, flow identification is necessary.";
leaf flow-identifier {
type string;
description
"The flow identifier.";
}
leaf matching-condition {
type string;
description
"The flow matching condition.";
}
leaf priority {
type int32;
description
"Policy priority. The low value is high priority.";
}
leaf mapping-sfc-name {
type string;
description
"The mapped service function name of the flow.";
}
}
}
container forwarding-policy-table {
description
"This policy is used to select SFIs defined in SFC and
connect them. This policy is used in Service Function
Forwarder (SFF). A SFF is responsible for delivering traffic
received from the network to one or more connected service
functions according to the policy table.";
list Forwarding-Policy-Table {
key index;
description
"The index of forwarding policy table.";
leaf index {
type int32;
description
"The index of forwarding policy table.";
}
leaf sff-name {
type string;
description "Name of Service Function Forwarder ";
}
}
}
}
<CODE ENDS>
This module shows statistical information related performance and faults in accordance with SFCs and SFPs.
<CODE BEGINS> file "history@2015-10-15.yang"
submodule history {
belongs-to sfc-control-planes {
prefix sfc-h;
}
import ietf-yang-types {
prefix yang;
revision-date 2013-07-15;
}
organization "ETRI.";
contact
"M-K. Shin mkshin@etri.re.kr
M-J Choi mjchoi@kangwon.ac.kr";
description
"This module shows statistical information related performance
and faults in accordance with SFCs and SFPs.";
revision 2015-10-15 {
reference
"draft-shin-sfc-control-plane-yang-00 -
Yang Data Model for Service Function Chaining Control Plane";
}
container performance {
description
"It monitors and stores time series data related performance."
;
list Performance {
key name;
description
"The name of service function.";
leaf name {
type string;
description
"The name of service function.";
}
leaf time {
type yang:date-and-time;
description
"The performance monitoring date.";
}
leaf aliveness {
type boolean;
description
"The aliveness flag of the service function.";
}
container resource-utilization {
description
"To be defined.";
leaf packet-rate {
type uint8;
description
"Percentage of current package rate utilization.";
}
leaf bandwidth {
type uint8;
description
"Percentage of bandwidth utilization.";
}
leaf cpu-usage {
type uint8;
description
"Percentage of CPU utilization.";
}
leaf memory-usage {
type uint8;
description
"Percentage of memory utilization.";
}
leaf available-memory {
type uint8;
description
"Available memory size of the service function in MB.";
}
leaf rib {
type uint8;
description
"Percentage of Routing Information Table utilization.";
}
leaf fib {
type uint8;
description
"Percentage of Forwarding Information Table
utilization.";
}
leaf sf-ports-bandwidth {
type uint8;
description
"Percentage of the port's supported bandwidth
utilization.";
}
}
}
}
container fault {
description
"It monitors and stores time series data related to faults
and events." ;
list fault {
key fault-name;
description
"The name occurred fault.";
leaf fault-name {
type string;
description
"The name occurred fault.";
}
leaf fault-occurrence-time {
type yang:date-and-time;
description
"The time of the fault occurrence.";
}
leaf fault-type {
type string;
description
"The type of occurred fault.";
}
leaf fault-occurrence-location {
type string;
description
"The location of fault occurrence.";
}
leaf fault-handling-action {
type string;
description
"The fault handing action: drop, bypass, use alternate
node.";
}
}
}
}
<CODE ENDS>
This module first detects faults and handles the detected faults in accordance with the fault handling action.
<CODE BEGINS> file "fault-handling@2015-10-15.yang"
submodule fault-handling {
belongs-to sfc-control-planes {
prefix sfc-fh;
}
organization "ETRI.";
contact
"M-K. Shin mkshin@etri.re.kr
M-J Choi mjchoi@kangwon.ac.kr";
description
"This module first detects faults and handles the detected
faults in accordance with the fault handling action. ";
revision 2015-10-15 {
reference
"draft-shin-sfc-control-plane-yang-00 -
Yang Data Model for Service Function Chaining Control Plane";
}
container fault-handling {
description
"This Container first detects faults and handles the detected
faults in accordance with the fault handling action. ";
list fault-handling {
key fault-name;
description
"The name of occurred fault.";
leaf fault-name {
type string;
description
"The fault handing action: drop, bypass, use alternate
node.";
}
leaf fault-type {
type enumeration {
enum node{
description
"Node";
}
enum link{
description
"Link";
}
enum path-failures{
description
"Path";
}
}
description
"The type of occurred fault.";
}
leaf fault-handling-action {
type enumeration {
enum bypass{
description
"Bypass";
}
enum use-alternate-node{
description
"Alternate node";
}
enum use-alternate-chain{
description
"Alternate chain";
}
enum drop-traffic{
description
"Drop the traffic";
}
}
description
"The fault handing action: drop, bypass, use alternate
node.";
}
}
}
}
<CODE ENDS>
Events such as loops detection, long unavailable forwarding path time, out of service of SFIs are defined.
<CODE BEGINS> file "event@2015-10-15.yang"
submodule event {
belongs-to sfc-control-planes {
prefix sfc-e;
}
organization "ETRI.";
contact
"M-K. Shin mkshin@etri.re.kr
M-J Choi mjchoi@kangwon.ac.kr";
description
"Events such as loops detection, long unavailable
forwarding path time, out of service of SFIs.";
revision 2015-10-15 {
reference
"draft-shin-sfc-control-plane-yang-00 -
Yang Data Model for Service Function Chaining Control Plane";
}
notification event {
description
"Events such as loops detection, long unavailable forwarding
path time, out of service of SFIs.";
leaf event-type {
type string;
description
"Event type.";
}
leaf severity {
type string;
description
"The severity of the event.";
}
leaf event-explanation {
type string;
description
"The detailed explanation of the event.";
}
}
}
<CODE ENDS>
TBD.
TBD.
| [RFC2119] | Bradner, S., "Key words for use in RFCs to Indicate Requirement Levels", BCP 14, RFC 2119, DOI 10.17487/RFC2119, March 1997. |
| [I-D.ietf-sfc-architecture] | Halpern, J. and C. Pignataro, "Service Function Chaining (SFC) Architecture", Internet-Draft draft-ietf-sfc-architecture-11, July 2015. |
| [I-D.ietf-sfc-control-plane] | Li, H., Wu, Q., Huang, O., Boucadair, M., Jacquenet, C., Haeffner, W., Lee, S., Parker, R., Dunbar, L., Malis, A., Halpern, J., Reddy, T. and P. Patil, "Service Function Chaining (SFC) Control Plane Components & Requirements", Internet-Draft draft-ietf-sfc-control-plane-03, January 2016. |
| [I-D.lee-sfc-dynamic-instantiation] | Lee, S., Pack, S., Shin, M. and E. Paik, "SFC dynamic instantiation", Internet-Draft draft-lee-sfc-dynamic-instantiation-01, October 2014. |
| [I-D.penno-sfc-yang] | Penno, R., Quinn, P., Zhou, D. and J. Li, "Yang Data Model for Service Function Chaining", Internet-Draft draft-penno-sfc-yang-14, January 2016. |