Benchmarking Workgroup S. Wu
Internet-Draft Juniper Networks
Intended status: Informational May 18, 2018
Expires: November 19, 2018
Network Service Layer Abstract Model
draft-xwu-bmwg-nslam-01
Abstract
While the networking technologies have evolved over the years, the
layered approach has been dominant in many network solutions. Each
layer may have multiple interchangeable, competing alternatives that
deliver a similar set of functionality. In order to provide an
objective benchmarking data among various implementations, the need
arises for a common abstract model for each network service layer,
with a set of required and optional specifications in respective
layers. Many overlay and or underlay solutions can be described
using these models.
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
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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 November 19, 2018.
Copyright Notice
Copyright (c) 2018 IETF Trust and the persons identified as the
document authors. All rights reserved.
This document is subject to BCP 78 and the IETF Trust's Legal
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carefully, as they describe your rights and restrictions with respect
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to this document. Code Components extracted from this document must
include Simplified BSD License text as described in Section 4.e of
the Trust Legal Provisions and are provided without warranty as
described in the Simplified BSD License.
Table of Contents
1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . 2
1.1. Terminology . . . . . . . . . . . . . . . . . . . . . . . 3
1.2. Purpose of The Document . . . . . . . . . . . . . . . . . 3
1.3. Conventions Used in This Document . . . . . . . . . . . . 3
2. Network Service Framework . . . . . . . . . . . . . . . . . . 4
2.1. Node . . . . . . . . . . . . . . . . . . . . . . . . . . 4
2.2. Topology . . . . . . . . . . . . . . . . . . . . . . . . 6
2.3. Infrastructure . . . . . . . . . . . . . . . . . . . . . 7
2.4. Services . . . . . . . . . . . . . . . . . . . . . . . . 8
3. Service Models . . . . . . . . . . . . . . . . . . . . . . . 9
3.1. Layer 2 Ethernet Service Model . . . . . . . . . . . . . 9
3.2. Layer 3 Service Model . . . . . . . . . . . . . . . . . . 10
3.3. Infrastructure Service Model . . . . . . . . . . . . . . 10
3.4. Node Level Features . . . . . . . . . . . . . . . . . . . 11
3.5. Common Service Specification . . . . . . . . . . . . . . 11
3.6. Common Network Events . . . . . . . . . . . . . . . . . . 12
3.6.1. Event Attributes . . . . . . . . . . . . . . . . . . 12
3.6.2. Hardware Related . . . . . . . . . . . . . . . . . . 13
3.6.3. Software Component . . . . . . . . . . . . . . . . . 13
3.6.4. Protocol Events . . . . . . . . . . . . . . . . . . . 14
3.6.5. Redundancy Failover . . . . . . . . . . . . . . . . . 14
4. Use of Network Service Layer Abstract Model . . . . . . . . . 14
5. Acknowledgements . . . . . . . . . . . . . . . . . . . . . . 15
6. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 15
7. Security Considerations . . . . . . . . . . . . . . . . . . . 15
8. References . . . . . . . . . . . . . . . . . . . . . . . . . 15
8.1. Normative References . . . . . . . . . . . . . . . . . . 15
8.2. Informative References . . . . . . . . . . . . . . . . . 15
Author's Address . . . . . . . . . . . . . . . . . . . . . . . . 16
1. Introduction
This document provides a reference model for common network service
framework. The main purpose is to abstract service model for each
network layer with a small set of key specifications. This is
essential to characterize the capability and capacity of a production
network, a target network design. A complete service model mainly
includes
Infrastructure - devices, links, and other equipment.
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Services - network applications provisioned. It is often defined
as device configuration and or resource allocation.
Capacity - A set of objects dynamically created for both control
and forwarding planes, such as routes, traffic, subscribers and
etc. In some cases, the amount and types of traffic may impact
control plane objects, such as multicast or ethernet networks.
Performance Metrics - infrastructure resource utilization.
1.1. 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 RFC 2119 [RFC2119].
1.2. Purpose of The Document
Many efforts to YANG model and OpenConfig collaboration are well
under way. This document specifies a higher layer abstraction that
reuses a small subset of YANG keywords for service description
purpose. It SHALL NOT be used for production provisioning purpose.
Instead, it can be adopted for design spec, capacity planning,
product benchmarking and test setup.
The specification described in this document SHALL be used for
outline service requirements from customer perspective, instead of
network implementation mechanism from operators perspective.
1.3. Conventions Used in This Document
Descriptive terms can quickly become overloaded. For consistency,
the following definitions are used.
o Node - The name for an attrubute.
o Brackets "[" and "]" enclose list keys.
o Abbreviations before data node names: "rw" means configuration
data (read-write), and "ro" means state data (read-only).
o Parentheses enclose choice and case nodes, and case nodes are also
marked with a colon (":").
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2. Network Service Framework
The network service layer abstract model is illustrated by Figure 1.
This shows a stack of components to enable end-to-end services. Not
all components are required for a given service. A common use case
is to pick one component as target service with a detailed profile,
with the remaining components as supporting technologies using
default profiles.
Network Service Layer Abstract Model
+---+-+-+-+---+-+-+-+-+
| S |L|L| | |L| |L| |
| E |2|2|V| E |3|M|U|6|
| R |V|C|P| V |V|V|B|P|
| V |P|K|L| P |P|P|G|E|
| I |N|T|S| N |N|N|P| |
| C +-+-+-+-+-+-+-+-+-+
| E | L2SVC | L3SVC |
+---+-------+---------+
| | BGP |
| I +-----------------+
| N | Transport |
| F +-----------------+
| R | IGP |
| A +-----------------+
| | Bridging |
+---+---------+-------+
| T | | Active|
| O | Logical |Standby|
| P +---------+ M-Home|
| O | Physical| L/B |
+---+-+-+-+-+-+-+-+-+-+
| N |I| | | | |C| | |I|
| O |N|F|Q| | |G|N|N|S|
| D |T|A|O|F|G|S|S|S|S|
| E |F|B|S|W|R|S|R|F|U|
+---+-+-+-+-+-+-+-+-+-+
Figure 1
2.1. Node
A network node or a network device processes and forwards traffic
based on predefined or dynamically learned policies. This section
covers standalone features like the following:
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o INTF - Network interfaces that provides internal or external
connectivity to adjacent devices. Only physical properties of the
interfaces are of concern in this level. The interfaces can be
physical or logical, wired or wireless.
o FAB - Fabric capacity. It provides redundancy and cross connect
within the same network device among various linecards or
interfaces
o QOS - Quality of Services. Traffic queuing, buffering, and
congestion management technologies are used in this level
o FW - Firewall filters or access control list. This commonly
refers to stateless packet inspection and filtering. Stateful
firewall is out of scope of this document. Number of filters
daisy chained on a given protocol family, number of terms within
same filter, and depth of packet inspection can all affect speed
and latency of traffic forwarding. It also provides necessary
security protection of node, where protocol traffic may be
affected.
o GR - Graceful Restart per protocol. It needs to cooperate with
adjacent node
o CGSS - Controller Graceful / Stateful Switchover. A network
device often has two redundant controllers to minimize the
disruption in event of catastrophic failure on the primary
controller. This is accomplished via real time state
synchronization from the primary to the backup controller. It,
however, should be used along with either NSR or NSF to achieve
optimal redundancy.
o NSR - Non-Stop Routing - hitless failover of route processor. It
maintains an active copy of route information base (RIB) as well
as state for protocol exchange so that the protocol adjacency is
not reset.
o NSF - Non-Stop Forwarding for layer 2 traffic, including layer 2
protocols such as spanning tree state
o ISSU - In Service Software Upgrade - Sub-second traffic loss in
many modern routing platforms. The demand for this feature
continues to grow from the field. Some study shows that the
downtime due to software upgrade is greater than that caused by
unplanned outages.
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2.2. Topology
Placement of network devices and corresponding links plays an
important role for optimal traffic forwarding. There are two types
of topologies:
o Physical Topology - Actual physical connectivity via fiber, coax,
cat5 or even wireless. That could be a ring, bus, star or matrix
topology. Even though all can be modeled using point-to-point
connections.
o Logical Topology - With aggregated ethernet, extended dot1q
tunneling, or VxLAN, a logical or virtual topology can be easily
created spanning across geography boundaries. Recent development
of multi-chassis, virtual-chassis, node-slicing technologies, and
multiple logical units within a single physical node have enabled
logical topology deployment more flexible and agile.
With various topology, the following functionalities need to be taken
into consideration for feature design and validation.
o Active-Standby - 1:1 or 1:n support. The liveness detection is
essential to trigger failover.
o M-Home - Multi-homing support. A customer edge (CE) device can be
homed to 2 or more Provider Edge (PE) devices at the same time.
This is a common redundancy design in layer 2 service offering
o L/B - Load Balancing - When multiple diverse paths exist for a
given destination, it is important to achieve load balancing based
on multiple criteria, such as per packet, or per prefix.
Sometimes, cascading effect can make issues more complex and
harder to resolve
The topology, regardless of physical or virtual, can be better
depicted using a collection of nodes and point-to-point links. Some
broadcast network, or ring topology, can also be abstracted using
same collection of point-to-point links. For example, in a wireless
LAN network, each client is a node with wireless LAN NIC as its
physical interface. The access point is the node, at which all WLAN
cients terminate with airwaves. The Service Set IDentifier (SSID) on
this access point can be considered as part of broadcast domain with
many pseudo-ports taking airwave terminations from clients.
The default link id can use srcnode-dstnode-linkseq to uniquely
identify a link in this topology. If this is a link connecting two
ports on the same node, it can use link-id of srcnode-srcnode-
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linkseq-portseq. Additional attributes of the node can be added with
proper placement for auto topology diagram.
Network Topology Definition
node-id-1 {
maker: maker_name,
model: model_name,
controller: controller-type,
mgmt_ip: mgmt_ip_address,
links: {
link-id-1 {
name: link_name,
connector: 'sfpp',
attr: ['10G', 'Ethernet'],
node_dst: destination node-id,
link_seq: sequence number for links between the node pair
...
}
}
...
}
node-id-2 {
...
}
Figure 2
2.3. Infrastructure
Network infrastructure here refers to a list of protocols and
policies for a data center network, an enterprise network, or a core
backbone in a service provider network.
o Bridging - Spanning Tree Protocol (STP) and its various flavors,
802.1q tunneling, Q-in-Q, VRRP and etc
o IGP - Interior Gateway Protocol - some common choices are OSPF,
IS-IS, RIP, RIPng. For multicast, choices are PIM and its various
flavors including MSDP, Bootstrap, DVMRP
o Transport - Tunnel technologies including
* MPLS - Multi-Protocol Label Switching - most commonly used in
service provider network
+ LDP - Label distribution protocol - including mLDP and LDP
Tunneling through RSVP LSPs
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+ RSVP - Resource Reservation Protocol - including P2MP and
its various features like Fast ReRoute - FRR.
* IPSec - IPSec Tunnel with AH or ESP
* GRE - Generic Routing Encapsulation (GRE) tunnels provides a
flexible direct adjacency between two remote routers
* VxLAN - In data center interconnect (DCI) solutions, VxLAN
encapsulation provides data plane for layer 2 frames
o BGP - Define families and their sub-SAFI deployed, as well as
route reflector topology.
2.4. Services
Previous sections mostly outline an operator's implementation of the
network, while customers may not necessarily care about these. This
section defines service profiles from customer's view.
o Layer 2 Services
* Layer 2 VPN - RFC 6624
* Martini Layer 2 Circuit - RFC 4906
* Virtual Private LAN Services - RFC 4761
* Ethernet VPN - RFC 7432
o Layer 3 Services
* Type 5 Route for EVPN - draft-ietf-bess-evpn-prefix-
advertisement-05
* Layer 3 VPN - RFC 4364
* Labled Unicast BGP - RFC 3107
* Draft Rosen MVPN - RFC 6037
* NG MVPN - RFC 6513
* 6PE - RFC 4798
In next section, an abstract model is proposed to identify key
metrics for both layer 2 and layer 3 model
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3. Service Models
A service model is a high level abstraction of network deployment
from bottom up. It defines a set of common key characteristics of
customer traffic profile in both control and forwarding planes. The
network itself should be considered as a blackbox and deliver the
services regardless of types of network equipment vendor or network
technologies.
The abstraction removes some details like specific IP address
assignment, and favors address range and its distribution. The goal
is to describe aggregated network behavior instead of granular
network element configuration. It is up to implementation to map
aggregated metrics to actual configuration for the network devices,
protocol emulator and traffic genrator.
A single network may be comprised of multiple instances of service
models defined below.
3.1. Layer 2 Ethernet Service Model
The metrics outlined below are for layer 2 network services typically
within a data center, data center interconnect, metro ethernet, or
layer 2 domain over WAN or even inter-carrier.
o service-type: identityref, ELAN, ELINE, ETREE
o sites-per-instance: uint32, an average number of sites a layer 2
instance may span across
o global-mac-count: uint32, Global MAC from all attachment circuits,
local and remote. This is probably the most important metric that
determines the capacity requirements in layer 2 for both control
and forwarding planes
o interface-mac-max: uint32, maximum number of locally learned MAC
addresses per logical interface, aka attachment circuit
o single-home-segments: uint32, number of single homed ethernet
segments per service instance
o multi-home-segments: uint32, number of multi homed ethernet
segments per layer 2 service instance
o service-instance-count: uint32, total number of layer 2 service
instances. Typically, one customer is
o traffic-type: list, {known-unicast: %, multicast, %, broadcast: %,
unknown-unicast: %}
o traffic-frame-size: list, predefined mixture of traffic frame size
distribution
o traffic-load: speed of traffic being sent towards the network.
This can be defined as frame per second (fps), or actual speed in
bps. This is particular important whenever some component along
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forwarding path is implemented in software, the throughput might
be affected significantly at high speed
o traffic-flow: A distribution of flows. This may affect efficient
use of load-balancing techniques and resource consumption. More
details discussed in later section of this document.
o layer3-gateway-count: uint32, number of layer 2 service instances
that also provide layer 3 gateway service
o arpnp-table-size: uint32. This is only relevant with presence of
layer 3 gateway
Integrated routing and bridging (IRB) and EVPN Type 5 route have
blurred boundaries between layer 2 and layer 3 services.
3.2. Layer 3 Service Model
This section outlines traffic type, layer 3 protocol families, layer
3 prefixes distribution, layer 3 traffic flow and packet size
distributions.
o proto-family: protocol family are defined with three sub-
attributes. The list may grow as the complexity
* proto - list: inet, inet6, iso
* type - list: unicast, mcast, segment, labeled
* vpn - list, true, false
o prefix-count, uint32, total unique prefixes
o prefix-distrib, list of prefix length size and percentage. This
could be a distribution pattern, such as uniform, random. Or
simply top representation of prefix lengths
o bgp-path-count, uint32, total BGP paths
o bgp-path-distrib, top representation of number of paths per prefix
o traffic-frame-size, similar to traffic-frame-size in layer 2
model. The focus is on the MTU size on each protocol interfaces
and the impact of fragmentation
o traffic-flow, similar to traffic-flow in layer 2 model, it focuses
on a set of labels, source and destination addresses as well as
ports
o traffic-load, similar to traffic-load in layer 2 model
o ifl-count, uint32,
o vpn-count, uint32,
3.3. Infrastructure Service Model
o bgp-peer-ext-count, uint32, number of eBGP peers
o bgp-peer-int-count, uint32, number of iBGP peers
o bgp-path-mtu, list, true or false. Larger path mtu helps
convergence
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o bgp-hold-time-distrib, list of top hold-time values and their
respective percentage out of all peers.
o bgp-as-path-distrib, list of top as-path lengths and their
respective percentage of all BGP paths
o bgp-community-distrib, list of top community size and their
respective percentage out of all BGP paths
o mpls-sig, list, MPLS signaling protocol, rsvp or ldp
o rsvp-lsp-count-ingress, uint32, total ingress lsp count
o rsvp-lsp-count-transit, uint32, total transit lsp count
o rsvp-lsp-count-egress, uint32, total egress lsp count
o ldp-fec-count, uint32, total forwarding equivalence class
o rsvp-lsp-protection, list, link-node, link, frr
o ospf-interface-type, list, point-to-point, broadcast, non-
broadcast multi-access
o ospf-lsa-distrib, list. OSPF Link Statement Advertisement
distribution is comprised of those for core router in backbone
area, and internal router in non-Backbone areas. A common
modeling can include number of LSAs per OSPF LSA type
o ospf-route-count, list, total OSPF routes in both backbone and
non-backbone areas
o isis-lsp-distrib, list, similar to ospf-lsa-distrib
o isis-route-count, list, total IS-IS routes in both level-1 and
level-2 areas
TODO: bridging, OAM, EOAM, BFD and etc
3.4. Node Level Features
TODO: node level feature set
3.5. Common Service Specification
For most network services, regardless of layer 2 or layer 3, protocol
families, the following needs to be considered when measuring network
capacity and baseline.
o rib-learning-time, uint32 in seconds. This indicates show quickly
the route processor learns routing objects either locally and
remotely
o fib-learning-time. In large routing system, forwarding engine
residing on separate hardware from controller, takes additional
time to install all forwarding entries learned by controller.
o convergence-time, this is could be as a result of many events,
such as uplink failure, ae member link failure, fast reroute,
local repair, upstream node failure and etc
o multihome-failover-time, this refers to traffic convergence in a
topology where a customer edge (CE) device is connected to two or
more provider edge (PE) devices.
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o issu-dark-window-size. Unlike NSR, the goal of ISSU is not zero
packet loss. Instead, there will be a few seconds, or in some
cases, sub-second dark window where it sees both total packet loss
for both transit and or host bound protocol traffic.
o cpu-util, total CPU utilization of the controllers in stead state
o cpu-util-peak, Peak CPU utilization on the controller in event of
failure, and convergence
o mem-util, total memory utilization of the controllers in steady
state
o mem-util-peak, total memory utilization on the controller in event
of failure and convergence
o processes, list of top processes running on the controllers with
their CPU and memory utilization.
o lc-cpu-util, top CPU utilization on the line cards
o lc-cpu-util-peak, maximum peak CPU utilization among all line
cards in event of failure and convergence
o lc-mem-util, top memory utilization on the line cards
o lc-mem-util-peak, maximum peak memory utilization among all line
cards in event of failure and convergence
o throughout, in both pps and bps. This is measured with zero
packet loss. For virtualized environment, throughput is sometimes
measured with a small loss tolerance given the nature of shared
resource
o traffic performance, in both pps and bps. It is measured the rate
of traffic received by pumping oversubscribed traffic at ingress
o latency in us. this is more important within a local data center
environment rather than DCI over wide area network. Use of
extensive firewall filter or access control lists may affect
latency
o Out of Order Packet - This can happen in intra-node or over ECMP
where different paths have large latency/delay variations.
The list of metrics can be used for network monitoring during network
resiliency test. This is to understand how quickly a network service
can restore during various events and failures
3.6. Common Network Events
A list of events is defined to characterize network resiliency.
These attributes require that the provider networks have diverse
paths and node redundancy built-in. They directly affect service
level agreement and network availability.
3.6.1. Event Attributes
Each network or system event may each be defined with the following
aspects
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o event-iteration, uint16, event to be repeated
o event-interval, unit16, seconds in between consecutive events
o event-dist, list, random, equal, or other type of event scheduling
o event-timeout, uint16, seconds when a single event is expected to
complete
o event-convergence, uint16, seconds before the network can be
recovered
3.6.2. Hardware Related
Some hardware failures can not easily replicated, or even simulated
in a lab environment, like the memory errors. A system or network
should be equipped to monitor, detect and contain the impact to avoid
global catastrohpic failure that may proagate beyond a single node or
the regional network.
o hw-mod-yank: hardware module removal and insertion.
o hw-interface: Transceiver on/off or any other simulated link
failures.
o hw-storage: storage failure, ether local or network attached.
o hw-power: unplanned power failure.
o hw-controller: Controller failure
o hw-memory: memory errors
3.6.3. Software Component
o sw-daemon-watchdog-loss: Induced CPU hog that trigger watchdog
failure
o sw-daemon-restart-graceful: Graceful software daemon restart.
o sw-daemon-restart-kill: The process is killed and the daemon was
forced to restart
o sw-daemon-panic: Sometimes a panic can introduced to trigger a
coredump of software daemon along with restart.
o sw-os-panic: network operating system may panic under various
situations. Many network products with a console access support
OS panic with a special sequence keystroke. Sometimes it may also
generate a coredump for further debug
o sw-upgrade: In many provider networks, the most downtime actually
come from scheduled maintenance, especially software or firmware
upgrade to provide better feature set or as a result of security
patch. It is important to understand the downtime requirement for
a routine software upgrade on a given network device or the
devices in the network. This often presents a challenge to the
access network.
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3.6.4. Protocol Events
o protocol-keepalive-loss: Loss of keepalive, such as hellos for
routing-protocols like OSPF and BGP
o oam-keepalive-loss: there are many OAM protocols, such as EOAM,
MPLS OAM, LACP, one of their main purposes is to detect
reachability. This is different from routing protocols keepalive
o protocol-adjacency-reset: clear all protocol neighbors and any
routes or link states learned from the neighbor
o protocol-db-purge: remove all database objects learned from a
particular neighbor, or a group of neighbors, or all neigbors.
The database maybe original set of state learned from neighbors,
or the consolidated database.
3.6.5. Redundancy Failover
The network protocols and design have a lot of redundancy built-in.
It is important to benchmark their effectiveness.
o ha-lag-links: measure packet loss in milliseconds when member
link(s) of a link aggregation group is torn down. In case of
protected interface, traffic should failover seamlessly to the
backup interface in event of primary link failure
o ha-controller: In a system with redundant controller, measure the
network recovery time when the primary controller fails. If the
advanced non-stop routing/forwarding is enabled, the network
should only experience zero or sub-second traffic loss.
o ha-multihome: in addition to device level redundancy, many
protocols support network layer redundancy though multihoming such
as EVPN.
o ha-mpls-frr: MPLS RSVP Fast ReRoute provides core network
redundancy
o ha-uplink: the core network is typically designed to provide path
diversity for edge devices, at either layer 2 and layer 3
connectivity. The resiliency of network is measured by how fast
the system detects the failure and reroute the traffic
4. Use of Network Service Layer Abstract Model
The primary goal is to characterize and document a complex network
using a simplified service model. While eliminating many details
such as address assignment, actual route or mac entries, it retains a
set of key network information, including services, scale, and
performance profiles. This can be used to validate how well each
underlying solution performs when delivering same set of services.
The model can also be used to build a virtualized topology with both
static and dynamic scale closely resemble to a real network. This
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eases network design and benchmarking, and helps capacity planning by
studying the impact with changes to a specific dimension.
5. Acknowledgements
The authors appreciate and acknowledge comments from Al Morton and
others based on initial discussions.
6. IANA Considerations
This memo includes no request to IANA.
All drafts are required to have an IANA considerations section (see
Guidelines for Writing an IANA Considerations Section in RFCs
[RFC5226] for a guide). If the draft does not require IANA to do
anything, the section contains an explicit statement that this is the
case (as above). If there are no requirements for IANA, the section
will be removed during conversion into an RFC by the RFC Editor.
7. Security Considerations
All drafts are required to have a security considerations section.
See RFC 3552 [RFC3552] for a guide.
8. References
8.1. Normative References
[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>.
[RFC3552] Rescorla, E. and B. Korver, "Guidelines for Writing RFC
Text on Security Considerations", BCP 72, RFC 3552,
DOI 10.17487/RFC3552, July 2003,
<https://www.rfc-editor.org/info/rfc3552>.
[RFC5226] Narten, T. and H. Alvestrand, "Guidelines for Writing an
IANA Considerations Section in RFCs", RFC 5226,
DOI 10.17487/RFC5226, May 2008,
<https://www.rfc-editor.org/info/rfc5226>.
8.2. Informative References
[L2SM] B. Wu et al, "A Yang Data Model for L2VPN Service
Delivery", 2017, <https://www.ietf.org/id/
draft-ietf-l2sm-l2vpn-service-model-02.txt>.
Wu Expires November 19, 2018 [Page 15]
Internet-Draft NSLAM May 2018
[RFC8049] Litkowski, S., Tomotaki, L., and K. Ogaki, "YANG Data
Model for L3VPN Service Delivery", RFC 8049,
DOI 10.17487/RFC8049, February 2017,
<https://www.rfc-editor.org/info/rfc8049>.
Author's Address
Sean Wu
Juniper Networks
2251 Corporate Park Dr.
Suite #200
Herndon, VA 20171
US
Phone: +1 571 203 1898
Email: xwu@juniper.net
Wu Expires November 19, 2018 [Page 16]