NFVRG R. Szabo
Internet-Draft Z. Qiang
Intended status: Informational Ericsson
Expires: April 21, 2016 M. Kind
Deutsche Telekom AG
October 19, 2015
Towards recursive virtualization and programming for network and cloud
resources
draft-unify-nfvrg-recursive-programming-02
Abstract
The introduction of Network Function Virtualization (NFV) in carrier-
grade networks promises improved operations in terms of flexibility,
efficiency, and manageability. NFV is an approach to combine network
and compute virtualizations together. However, network and compute
resource domains expose different virtualizations and programmable
interfaces. In [I-D.unify-nfvrg-challenges] we argued for a joint
compute and network virtualization by looking into different compute
abstractions.
In this document we analyze different approaches to orchestrate a
service graph with transparent network functions relying on a public
telecommunication network and ending in a commodity data center. We
show that a recursive compute and network joint virtualization and
programming has clear advantages compared to other approaches with
separated control between compute and network resources. In
addition, the joint virtualization will have cost and performance
advantages by removing additional virtualization overhead. The
discussion of the problems and the proposed solution is generic for
any data center use case; however, we use NFV as an example.
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This Internet-Draft will expire on April 21, 2016.
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Table of Contents
1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . 2
2. Terms and Definitions . . . . . . . . . . . . . . . . . . . . 3
3. Use Cases . . . . . . . . . . . . . . . . . . . . . . . . . . 4
3.1. Black Box DC . . . . . . . . . . . . . . . . . . . . . . . 4
3.1.1. Black Box DC with L3 tunnels . . . . . . . . . . . . . . 5
3.1.2. Black Box DC with external steering . . . . . . . . . . . 6
3.2. White Box DC . . . . . . . . . . . . . . . . . . . . . . . 8
3.3. Conclusions . . . . . . . . . . . . . . . . . . . . . . . . 9
4. Recursive approach . . . . . . . . . . . . . . . . . . . . . 10
4.1. Virtualization . . . . . . . . . . . . . . . . . . . . . . 11
4.1.1. The virtualizer's data model . . . . . . . . . . . . . . 13
5. Relation to ETSI NFV . . . . . . . . . . . . . . . . . . . . 20
6. Examples . . . . . . . . . . . . . . . . . . . . . . . . . . 23
6.1. Infrastructure reports . . . . . . . . . . . . . . . . . . 24
6.2. Simple requests . . . . . . . . . . . . . . . . . . . . . . 29
7. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 31
8. Security Considerations . . . . . . . . . . . . . . . . . . . 31
9. Acknowledgement . . . . . . . . . . . . . . . . . . . . . . . 32
10. Informative References . . . . . . . . . . . . . . . . . . . 32
Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . 32
1. Introduction
To a large degree there is agreement in the research community that
rigid network control limits the flexibility of service creation. In
[I-D.unify-nfvrg-challenges]
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o we analyzed different compute domain abstractions to argue that
joint compute and network virtualization and programming is needed
for efficient combination of these resource domains;
o we described challenges associated with the combined handling of
compute and network resources for a unified production
environment.
Our goal here is to analyze different approaches to instantiate a
service graph with transparent network functions into a commodity
Data Center (DC). More specifically, we analyze
o two black box DC set-ups, where the intra-DC network control is
limited to some generic compute only control programming
interface;
o a white box DC set-up, where the intra-DC network control is
exposed directly to for a DC external control to coordinate
forwarding configurations;
o a recursive approach, which illustrates potential benefits of a
joint compute and network virtualization and control.
The discussion of the problems and the proposed solution is generic
for any data center use case; however, we use NFV as an example.
2. Terms and Definitions
We use the terms compute and "compute and storage" interchangeably
throughout the document. Moreover, we use the following definitions,
as established in [ETSI-NFV-Arch]:
NFV: Network Function Virtualization - The principle of separating
network functions from the hardware they run on by using virtual
hardware abstraction.
NFVI: NFV Infrastructure - Any combination of virtualized compute,
storage and network resources.
VNF: Virtualized Network Function - a software-based network
function.
MANO: Management and Orchestration - In the ETSI NFV framework
[ETSI-NFV-MANO], this is the global entity responsible for
management and orchestration of NFV lifecycle.
Further, we make use of the following terms:
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NF: a network function, either software-based (VNF) or appliance-
based.
SW: a (routing/switching) network element with a programmable
control plane interface.
DC: a data center is an interconnection of Compute Nodes (see below)
with a data center controller, which offers programmatic resource
control interface to its clients.
CN: a server, which is controlled by a DC control plane and provides
execution environment for virtual machine (VM) images such as
VNFs.
3. Use Cases
Service Function Chaining (SFC) looks into the problem how to deliver
end-to-end services through the chain of network functions (NFs).
Many of such NFs are envisioned to be transparent to the client,
i.e., they intercept the client connection for adding value to the
services without the knowledge of the client. However, deploying
network function chains in DCs with Virtualized Network Functions
(VNFs) are far from trivial [I-D.ietf-sfc-dc-use-cases]. For
example, different exposures of the internals of the DC will imply
different dynamisms in operations, different orchestration
complexities and may yield for different business cases with regards
to infrastructure sharing.
We investigate different scenarios with a simple NF forwarding graph
of three VNFs (o->VNF1->VNF2->VNF3->o), where all VNFs are deployed
within the same DC. We assume that the DC is a multi-tier leaf and
spine (CLOS) and that all VNFs of the forwarding graph are bump-in-
the-wire NFs, i.e., the client cannot explicitly access them.
3.1. Black Box DC
In Black Bock DC set-ups, we assume that the compute domain is an
autonomous domain with legacy (e.g., OpenStack) orchestration APIs.
Due to the lack of direct forwarding control within the DC, no native
L2 forwarding can be used to insert VNFs running in the DC into the
forwarding graph. Instead, explicit tunnels (e.g., VxLAN) must be
used, which need termination support within the deployed VNFs.
Therefore, VNFs must be aware of the previous and the next hops of
the forwarding graph to receive and forward packets accordingly.
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3.1.1. Black Box DC with L3 tunnels
Figure 1 illustrates a set-up where an external VxLAN termination
point in the SDN domain is used to forward packets to the first NF
(VNF1) of the chain within the DC. VNF1, in turn, is configured to
forward packets to the next SF (VNF2) in the chain and so forth with
VNF2 and VNF3.
In this set-up VNFs must be capable of handling L3 tunnels (e.g.,
VxLAN) and must act as forwarders themselves. Additionally, an
operational L3 underlay must be present so that VNFs can address each
other.
Furthermore, VNFs holding chain forwarding information could be
untrusted user plane functions from 3rd party developers.
Enforcement of proper forwarding is problematic.
Additionally, compute only orchestration might result in sub-optimal
allocation of the VNFs with regards to the forwarding overlay, for
example, see back-forth use of a core switch in Figure 1.
In [I-D.unify-nfvrg-challenges] we also pointed out that within a
single Compute Node (CN) similar VNF placement and overlay
optimization problem may reappear in the context of network interface
cards and CPU cores.
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| A A
+---+ | S |
|SW1| | D |
+---+ | N | P
/ \ V | H
/ \ | Y
| | A | S
+---+ +-+-+ | | I
|SW | |SW | | | C
,+--++.._ _+-+-+ | | A
,-" _|,,`.""-..+ | C | L
_,,,--"" | `. |""-.._ | L |
+---+ +--++ `+-+-+ ""+---+ | O |
|SW | |SW | |SW | |SW | | U |
+---+ ,'+---+ ,'+---+ ,'+---+ | D |
| | ,-" | | ,-" | | ,-" | | | |
+--+ +--+ +--+ +--+ +--+ +--+ +--+ +--+ | |
|CN| |CN| |CN| |CN| |CN| |CN| |CN| |CN| | |
+--+ +--+ +--+ +--+ +--+ +--+ +--+ +--+ V V
| | |
+-+ +-+ +-+ A
|V| |V| |V| | L
|N| |N| |N| | O
|F| |F| |F| | G
|1| |3| |2| | I
+-+ +-+ +-+ | C
+---+ --1>-+ | | +--<3---------------<3---+ | | A
|SW1| +-2>-----------------------------2>---+ | L
+---+ <4--------------+ V
<<=============================================>>
IP tunnels, e.g., VxLAN
Figure 1: Black Box Data Center with VNF Overlay
3.1.2. Black Box DC with external steering
Figure 2 illustrates a set-up where an external VxLAN termination
point in the SDN domain is used to forward packets among all the SFs
(VNF1-VNF3) of the chain within the DC. VNFs in the DC need to be
configured to receive and send packets between only the SDN endpoint,
hence are not aware of the next hop VNF address. Shall any VNFs need
to be relocated, e.g., due to scale in/out as described in
[I-D.zu-nfvrg-elasticity-vnf], the forwarding overlay can be
transparently re-configured at the SDN domain.
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Note however, that traffic between the DC internal SFs (VNF1, VNF2,
VNF3) need to exit and re-enter the DC through the external SDN
switch. This, certainly, is sub-optimal an results in ping-pong
traffic similar to the local and remote DC case discussed in
[I-D.zu-nfvrg-elasticity-vnf].
| A A
+---+ | S |
|SW1| | D |
+---+ | N | P
/ \ V | H
/ \ | Y
| | ext port A | S
+---+ +-+-+ | | I
|SW | |SW | | | C
,+--++.._ _+-+-+ | | A
,-" _|,,`.""-..+ | C | L
_,,,--"" | `. |""-.._ | L |
+---+ +--++ `+-+-+ ""+---+ | O |
|SW | |SW | |SW | |SW | | U |
+---+ ,'+---+ ,'+---+ ,'+---+ | D |
| | ,-" | | ,-" | | ,-" | | | |
+--+ +--+ +--+ +--+ +--+ +--+ +--+ +--+ | |
|CN| |CN| |CN| |CN| |CN| |CN| |CN| |CN| | |
+--+ +--+ +--+ +--+ +--+ +--+ +--+ +--+ V V
| | |
+-+ +-+ +-+ A
|V| |V| |V| | L
|N| |N| |N| | O
|F| |F| |F| | G
|1| |3| |2| | I
+-+ +-+ +-+ | C
+---+ --1>-+ | | | | | | A
|SW1| <2-----+ | | | | | L
| | --3>---------------------------------------+ | |
| | <4-------------------------------------------+ |
| | --5>------------+ | |
+---+ <6----------------+ V
<<=============================================>>
IP tunnels, e.g., VxLAN
Figure 2: Black Box Data Center with ext Overlay
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3.2. White Box DC
Figure 3 illustrates a set-up where the internal network of the DC is
exposed in full details through an SDN Controller for steering
control. We assume that native L2 forwarding can be applied all
through the DC until the VNFs' port, hence IP tunneling and tunnel
termination at the VNFs are not needed. Therefore, VNFs need not be
forwarding graph aware but transparently receive and forward packets.
However, the implications are that the network control of the DC must
be handed over to an external forwarding controller (see that the SDN
domain and the DC domain overlaps in Figure 3). This most probably
prohibits clear operational separation or separate ownerships of the
two domains.
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| A A
+---+ | S |
|SW1| | D |
+---+ | N | P
/ \ | | H
/ \ | | Y
| | ext port | A | S
+---+ +-+-+ | | | I
|SW | |SW | | | | C
,+--++.._ _+-+-+ | | | A
,-" _|,,`.""-..+ | | C | L
_,,,--"" | `. |""-.._ | | L |
+---+ +--++ `+-+-+ ""+---+ | | O |
|SW | |SW | |SW | |SW | | | U |
+---+ ,'+---+ ,'+---+ ,'+---+ V | D |
| | ,-" | | ,-" | | ,-" | | | |
+--+ +--+ +--+ +--+ +--+ +--+ +--+ +--+ | |
|CN| |CN| |CN| |CN| |CN| |CN| |CN| |CN| | |
+--+ +--+ +--+ +--+ +--+ +--+ +--+ +--+ V V
| | |
+-+ +-+ +-+ A
|V| |V| |V| | L
|N| |N| |N| | O
|F| |F| |F| | G
|1| |3| |2| | I
+-+ +-+ +-+ | C
+---+ --1>-+ | | +--<3---------------<3---+ | | A
|SW1| +-2>-----------------------------2>---+ | L
+---+ <4--------------+ V
<<=============================================>>
L2 overlay
Figure 3: White Box Data Center with L2 Overlay
3.3. Conclusions
We have shown that the different solutions imply different operation
and management actions. From network operations point of view, it is
not desirable to run and manage similar functions several times (L3
blackbox DC case) - especially if the networking overlay can be
easily managed upfront by using a programmatic interface, like with
the external steering in black and whitebox DC scenarios.
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4. Recursive approach
We argued in [I-D.unify-nfvrg-challenges] for a joint software and
network programming interface. Consider that such joint software and
network abstraction (virtualization) exists around the DC with a
corresponding resource programmatic interface. A software and
network programming interface could include VNF requests and the
definition of the corresponding network overlay. However, such
programming interface is similar to the top level services
definition, for example, by the means of a VNF Forwarding Graph.
Figure 4 illustrates a joint domain virtualization and programming
setup. In Figure 4 "[x]" denotes ports of the virtualized data plane
while "x" denotes port created dynamically as part of the VNF
deployment request. Over the joint software and network
virtualization VNF placement and the corresponding traffic steering
could be defined in an atomic, which is orchestrated, split and
handled to the next levels (see Figure 5) in the hierarchy for
further orchestration. Such setup allows clear operational
separation, arbitrary domain virtualization (e.g., topology details
could be omitted) and constraint based optimization of domain wide
resources.
|
+-----------------------[x]--------------------+ A
|Domain 0 | | |O
| +--------[x]----------+ | |V
| | / \ | | |E
|Big Switch | -<--- --->-- | | |R
|with | / BiS-BiS \ | | |A
|Big Software | | +-->-+ +-->-+ | | | |R
|(BiS-BiS) | | | | | | | | | |C
| +--x-x----x-x----x-x--+ | |H
| | | | | | | | |I
| +-+ +-+ +-+ | |N
| |V| |V| |V| | |G V
| |N| |N| |N| | | N
| |F| |F| |F| | | F
| |1| |2| |3| | |
| +-+ +-+ +-+ | | F
| | | G
+----------------------------------------------+ V
Figure 4: Recursive Domain Virtualization and Joint VNF FG
programming: Overarching View
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+-------------------------|-----------------------------+ A
| +----------------------[x]---------------------+ AV | |
| | Domain 1 / \ | |N | |
| | | A | |F | |
| | Big Switch (BS) | | | | | |O
| | V | | |F | |V
| | / \ | |G | |E
| +-----------------[x]--------[x]---------------+ V1 | |R
| | | | |A
| +------------------|----------|----------------+ A | |R
| |Domain 2 | A | | | |C
| | V | | | | |H
| | +---[x]--------[x]----+ | |V | |I
| |Big Switch | / BiS-BiS \ | | |N | |N
| |with | / \ | | |F | |G
| |Big Software | | +-->-+ +-->-+ | | | | | |
| |(BiS-BiS) | | | | | | | | | |F | |V
| | +--x-x----x-x----x-x--+ | |G | |N
| | | | | | | | | |2 | |F
| | +-+ +-+ +-+ | | | |
| | |V| |V| |V| | | | |F
| | |N| |N| |N| | | | |G
| | |F| |F| |F| | | | |
| | |1| |2| |3| | | | |
| | +-+ +-+ +-+ | | | |
| +----------------------------------------------+ V | |
+-------------------------------------------------------+ V
Figure 5: Recursive Domain Virtualization and Joint VNF FG
programming: Domain Views
4.1. Virtualization
Let us first define the joint software and network abstraction
(virtualization) as a Big Switch with Big Software (BiS-BiS). A BiS-
BiS is a node abstraction, which incorporates both software and
networking resources with an associated joint software and network
control API (see Figure 6).
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API o __
| \
Software Ctrler \
API O-------------+ \ \
| \ \
Compute Ctrler \ |
| \ |
| +---------------------+ |
| | | | Joint Software &
| | {vCPU | | Network Ctrl API
| | memory | | o
| | storage} | | |
| | | | +---------------------+
| | | | | {{vCPU |
| |Compute Node | \ [1 memory 3]
| | | ==> | storage} |
| +----------x----------+ / [2 {port rate 4]
\ | | | switching delay}} |
+----------x----------+ | +---------------------+
| | | Big Switch &
[1 {port rate 3] | Big Software (BiS-BiS)
| switching delay} | | with joint
[2 4] / Software & Network Ctrler
| Network Element | /
+---------------------+ /
__/
Figure 6: Big Switch with Big Software definition
The configuration over a BiS-BiS allows the atomic definition of NF
placements and the corresponding forwarding overlay as a Network
Function - Forwarding Graph (NF-FG). The embedment of NFs into a
BiS-BiS allows the inclusion of NF ports into the forwarding overlay
definition (see ports a, b, ...,f in Figure 7). Ports 1,2, ..., 4
are seen as infrastructure ports while NF ports are created and
destroyed with NF placements.
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Step 1: Placement of NFs
Step 2: Interconnect NFs __ Step 1: Placement of NFs
\ with the forwarding
Compute Node \ overlay definition
+---------------------+ \
| +-+ +-+ +-+ | \ +-+ +-+ +-+
| |V| |V| |V| | | |V| |V| |V|
| |N| |N| |N| | | |N| |N| |N|
| |F| |F| |F| | | |F| |F| |F|
| |1| |2| |3| | | |1| |2| |3|
| +-+ +-+ +-+ | | +-+ +-+ +-+
| | +---.| |.---+ | | \ | | | | | |
| +------\ /------+ | ==> +--a-b----c-d----e-f--+
+----------x----------+ / | | | | | | | |
| | [1->+ +-->-+ +-->-+ | 3]
+----------x----------+ | | | |
| / \ | | [2 +->4]
[1->----->- -->---+ 3] | | |
| | | | +---------------------+
[2 +->4] / Big Switch with
| Network Element | / Big Software (BiS-BiS)
+---------------------+ /
__/
Figure 7: Big Switch with Big Software definition with a Network
Function - Forwarding Graph (NF-FG)
4.1.1. The virtualizer's data model
4.1.1.1. Tree view
module: virtualizer
+--rw virtualizer
+--rw id? string
+--rw name? string
+--rw nodes
| +--rw node* [id]
| +--rw id string
| +--rw name? string
| +--rw type string
| +--rw ports
| | +--rw port* [id]
| | +--rw id string
| | +--rw name? string
| | +--rw port_type string
| | +--rw port_data? string
| +--rw links
| | +--rw link* [src dst]
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| | +--rw id? string
| | +--rw name? string
| | +--rw src port-ref
| | +--rw dst port-ref
| | +--rw resources
| | +--rw delay? string
| | +--rw bandwidth? string
| +--rw resources
| | +--rw cpu string
| | +--rw mem string
| | +--rw storage string
| +--rw NF_instances
| | +--rw node* [id]
| | +--rw id string
| | +--rw name? string
| | +--rw type string
| | +--rw ports
| | | +--rw port* [id]
| | | +--rw id string
| | | +--rw name? string
| | | +--rw port_type string
| | | +--rw port_data? string
| | +--rw links
| | | +--rw link* [src dst]
| | | +--rw id? string
| | | +--rw name? string
| | | +--rw src port-ref
| | | +--rw dst port-ref
| | | +--rw resources
| | | +--rw delay? string
| | | +--rw bandwidth? string
| | +--rw resources
| | +--rw cpu string
| | +--rw mem string
| | +--rw storage string
| +--rw capabilities
| | +--rw supported_NFs
| | +--rw node* [id]
| | +--rw id string
| | +--rw name? string
| | +--rw type string
| | +--rw ports
| | | +--rw port* [id]
| | | +--rw id string
| | | +--rw name? string
| | | +--rw port_type string
| | | +--rw port_data? string
| | +--rw links
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| | | +--rw link* [src dst]
| | | +--rw id? string
| | | +--rw name? string
| | | +--rw src port-ref
| | | +--rw dst port-ref
| | | +--rw resources
| | | +--rw delay? string
| | | +--rw bandwidth? string
| | +--rw resources
| | +--rw cpu string
| | +--rw mem string
| | +--rw storage string
| +--rw flowtable
| +--rw flowentry* [port match action]
| +--rw port port-ref
| +--rw match string
| +--rw action string
| +--rw resources
| +--rw delay? string
| +--rw bandwidth? string
+--rw links
+--rw link* [src dst]
+--rw id? string
+--rw name? string
+--rw src port-ref
+--rw dst port-ref
+--rw resources
+--rw delay? string
+--rw bandwidth? string
Figure 8: Virtualizer's YANG data model: tree view
4.1.1.2. YANG Module
<CODE BEGINS> file "virtualizer.yang"
module virtualizer {
namespace "http://fp7-unify.eu/framework/virtualizer";
prefix virt;
organization "EU-FP7-UNIFY";
contact "Robert Szabo <robert.szabo@ericsson.com>";
description "data model for joint software and network
virtualization and resource control";
revision 2015-06-27 {
reference "Initial version";
}
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// REUSABLE GROUPS
grouping id-name {
description "used for key (id) and naming";
leaf id {
type string;
description "For unique key id";}
leaf name {
type string;
description "Descriptive name";}
}
grouping node-type {
description "For node type defintion";
leaf type{
type string;
mandatory true;
description "to identify nodes (infrastructure or NFs)";
}
}
// PORTS
typedef port-ref {
type string;
description "path to a port; can refer to ports at multiple
levels in the hierarchy";
}
grouping port {
description "Port definition: used for infrastructure and NF
ports";
uses id-name;
leaf port_type {
type string;
mandatory true;
description "Port type identification: abstract is for
technology independent ports and SAPs for technology specific
ports";}
leaf port_data{
type string;
description "Opaque data for port specific types";
}
}
grouping ports {
description "Collection of ports";
container ports {
description "see above";
list port{
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key "id";
uses port;
description "see above";
}
}
}
// FORWARDING BEHAVIOR
grouping flowentry {
leaf port {
type port-ref;
mandatory true;
description "path to the port";
}
leaf match {
type string;
mandatory true;
description "matching rule";
}
leaf action {
type string;
mandatory true;
description "forwarding action";
}
container resources{
uses link-resource;
description "network resources assigned to forwarding entry";
}
description "SDN forwarding entry";
}
grouping flowtable {
container flowtable {
description "Collection of flowentries";
list flowentry {
key "port match action";
description "Index list of flowentries";
uses flowentry;
}
}
description "See container description";
}
// LINKS
grouping link-resource {
description "Core networking characteristics / resources
(bandwidth, delay)";
leaf delay {
type string;
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description "Delay value with unit; e.g. 5ms";
}
leaf bandwidth {
type string;
description "Bandwithd value with unit; e.g. 10Mbps";
}
}
grouping link {
description "Link between src and dst ports with attributes";
uses id-name;
leaf src {
type port-ref;
description "relative path to the source port";
}
leaf dst {
type port-ref;
description "relative path to the destination port";
}
container resources{
uses link-resource;
description "Link resources (attributes)";
}
}
grouping links {
description "Collection of links in a virtualizer or a node";
container links {
description "See above";
list link {
key "src dst";
description "Indexed list of links";
uses link;
}
}
}
// CAPABILITIES
grouping capabilities {
description "For capability reporting: currently supported NF
types";
container supported_NFs { // supported NFs are enumerated
description "Collecction of nodes as supported NFs";
list node{
key "id";
description "see above";
uses node;
}
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}
// TODO: add other capabilities
}
// NODE
grouping software-resource {
description "Core software resources";
leaf cpu {
type string;
mandatory true;
description "In virtual CPU (vCPU) units";
}
leaf mem {
type string;
mandatory true;
description "Memory with units, e.g., 1Gbyte";
}
leaf storage {
type string;
mandatory true;
description "Storage with units, e.g., 10Gbyte";
}
}
grouping node {
description "Any node: infrastructure or NFs";
uses id-name;
uses node-type;
uses ports;
uses links;
container resources{
description "Software resources offer/request of the node";
uses software-resource;
}
}
grouping infra-node {
description "Infrastructure nodes wich can contain other nodes
as NFs";
uses node;
container NF_instances {
description "Hosted NFs";
list node{
key "id";
uses node;
description "see above";
}
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}
container capabilities {
description "Supported NFs as capability reports";
uses capabilities;
}
uses flowtable;
}
//======== Virtualizer ====================
container virtualizer {
description "Definition of a virtualizer instance";
uses id-name;
container nodes{
description "infra nodes, which embeds NFs and report
capabilities";
list node{
key "id";
uses infra-node;
description "see above";
}
}
uses links;
}
}
<CODE ENDS>
Figure 9: Virtualizer's YANG data model
5. Relation to ETSI NFV
According to the ETSI MANO framework [ETSI-NFV-MANO], an NFVO is
split into two functions:
o the orchestration of NFVI resources across multiple VIMs,
fulfilling the Resource Orchestration functions;
o The NFVO uses the Resource Orchestration functionality to provide
services that support accessing NFVI resources in an abstracted
manner independently of any VIMs, as well as governance of VNF
instances sharing resources of the NFVI infrastructure
Similarly, a VIM is split into two functions:
o Orchestrating the allocation/upgrade/release/reclamation of NFVI
resources (including the optimization of such resources usage),
and
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o managing the association of the virtualised resources to the
physical compute, storage, networking resources.
The functional split is shown in Figure 13.
+-------------------+
|NVFO |
| +--------------+ |
| |NFVO: | |
| |Service | |
| |Lifecycle | |
| |Management | |
| +------+-------+ |
| | |
| +------+-------+ |
| |NFVO: | |
| |Resrouce | |
| |Orchestration | |
| +--+---+----+--+ |
+-----|---|----|----+
/ | \
/---------/ | \------------\
/ | \
+-------------|-----+ +--------|----------+ +------|------------+
|VIM | | |VIM | | |VIM | |
| +----------+---+ | | +-----+--------+ | | +---+----------+ |
| |VIM: | | | |VIM: | | | |VIM: | |
| |Orchestration | | | |Orchestration | | | |Orchestration | |
| |& | | | |& | | | |& | |
| |Optimization | | | |Optimization | | | |Optimization | |
| +------+-------+ | | +------+-------+ | | +------+-------+ |
| | | | | | | | |
| +------+-------+ | | +------+-------+ | | +------+-------+ |
| |VIM: | | | |VIM: | | | |VIM: | |
| |Virtualized 2 | | | |Virtualized 2 | | | |Virtualized 2 | |
| |Pys mapping | | | |Pys mapping | | | |Pys mapping | |
| +--------------+ | | +--------------+ | | +--------------+ |
+-------------------+ +-------------------+ +-------------------+
Figure 10: Functional decomposition of the NFVO and the VIM according
to the ETSI MANO
If the Joint Software and Network Control API (Joint API) could be
used between all the functional components working on the same
abstraction, i.e., from the north of the VIM Virtualized to physical
mapping component to the south of the NFVO: Service Lifecycle
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Management as shown in Figure 11, then a more flexible virtualization
programming architecture could be created as shown in Figure 12.
+-------------------+
|NVFO |
| +--------------+ |
| |NFVO: | |
| |Service | |
| |Lifecycle | |
| |Management | |
| +------+-------+ |
| | | <-- Joint API
| +------+-------+ |
| |NFVO: | |
| |Resrouce | |
| |Orchestration | |
| +--+---+-------+ |
+-----|---|---------+
/ |
/---------/ | <-- Joint API
/ |
+-------------|-----+ +--------|----------+
|VIM | | |VIM | |
| +----------+---+ | | +-----+--------+ |
| |VIM: | | | |VIM: | |
| |Orchestration | | | |Orchestration | |
| |& | | | |& | |
| |Optimization | | | |Optimization | |
| +------+-------+ | | +------+-------+ |
| | | | | | <-- Joint API
| +------+-------+ | | +------+-------+ |
| |VIM: | | | |VIM: | |
| |Virtualized 2 | | | |Virtualized 2 | |
| |Pys mapping | | | |Pys mapping | |
| +--------------+ | | +--------------+ |
+-------------------+ +-------------------+
Figure 11: Functional decomposition of the NFVO and the VIM with the
Joint Software and Network control API
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+--------------+
| |
|Orchestration |
Domain 4 | |
+--+-----------+
**********************|******************
* +--------------+ |
* |NFVO: | |
* |Service | |
* |Lifecycle | |
* |Management | |
* +-------+------+ /
* | / <-- Joint API
* +-+---------+--+
* | |
* |Orchestration |
******************** * | |
+--------------+ * * +--+---+-------+ Domain 3
|NFVO: | * ********|***|*************************
|Service | * / |
|Lifecycle | /---------/ |
|Management | / * |
+---------+----+ | * |
| | * | <-- Joint API
+--+-------+---+* |
| |* |
|Orchestration |* |
| |* |
| |* |
+------+-------+* |
| * *********|********** <-- Joint API
+------+-------+* * +------+-------+ *
|VIM: |* * |VIM: | *
|Virtualized 2 |* * |Virtualized 2 | *
|Pys mapping |* * |Pys mapping | *
+--------------+* * +--------------+ *
Domain 1 * * Domain 2 *
************************* * *
Figure 12: Joint Software and Network Control API: Recurring Flexible
Architecture
6. Examples
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6.1. Infrastructure reports
Figure 13 and Figure 14 show a single node infrastructure report.
The example shows a BiS-BiS with two ports, out of which Port 0 is
also a Service Access Point 0 (SAP0).
20 CPU
+-----------+ 64GB MEM
SAP1--[0 BiS-BiS | 1TB STO
| (UUID13) |
+[2 1]+
| +-----------+ |
| |
| |
+-----------+ | | +-----------+
SAP0--[0 BiS-BiS 1]+ +[0 BiS-BiS 1]--SAP1
| (UUID11) | | (UUID12) |
| 2]-----------------[2 |
+-----------+ +-----------+
20 CPU 10 CPU
64GB MEM 32GB MEM
100TB STO 100TB STO
Figure 13: Single node infrastructure report example: Virtualization
view
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<virtualizer xmlns="http://fp7-unify.eu/framework/virtualizer">
<id>UUID001</id>
<name>Single node simple infrastructure report</name>
<nodes>
<node>
<id>UUID11</id>
<name>single Bis-Bis node</name>
<type>BisBis</type>
<ports>
<port>
<id>0</id>
<name>SAP0 port</name>
<port_type>port-sap</port_type>
<vxlan>...</vxlan>
</port>
<port>
<id>1</id>
<name>North port</name>
<port_type>port-abstract</port_type>
<capability>...</capability>
</port>
<port>
<id>2</id>
<name>East port</name>
<port_type>port-abstract</port_type>
<capability>...</capability>
</port>
</ports>
<resources>
<cpu>20</cpu>
<mem>64 GB</mem>
<storage>100 TB</storage>
</resources>
</node>
</nodes>
</virtualizer>
Figure 14: Single node infrastructure report example: xml view
Figure 15 and Figure 16 show a 3-node infrastructure report with 3
BiS-BiS nodes. Infrastructure links are inserted into the
virtualization view between the ports of the BiS-BiS nodes.
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20 CPU
+-----------+ 64GB MEM
SAP1--[0 BiS-BiS | 1TB STO
| (UUID13) |
+[2 1]+
| +-----------+ |
| |
| |
+-----------+ | | +-----------+
SAP0--[0 BiS-BiS 1]+ +[0 BiS-BiS 1]--SAP1
| (UUID11) | | (UUID12) |
| 2]-----------------[2 |
+-----------+ +-----------+
20 CPU 10 CPU
64GB MEM 32GB MEM
100TB STO 100TB STO
Figure 15: 3-node infrastructure report example: Virtualization view
<virtualizer xmlns="http://fp7-unify.eu/framework/virtualizer">
<id>UUID002</id>
<name>3-node simple infrastructure report</name>
<nodes>
<node>
<id>UUID11</id>
<name>West Bis-Bis node</name>
<type>BisBis</type>
<ports>
<port>
<id>0</id>
<name>SAP0 port</name>
<port_type>port-sap</port_type>
<vxlan>...</vxlan>
</port>
<port>
<id>1</id>
<name>North port</name>
<port_type>port-abstract</port_type>
<capability>...</capability>
</port>
<port>
<id>2</id>
<name>East port</name>
<port_type>port-abstract</port_type>
<capability>...</capability>
</port>
</ports>
<resources>
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<cpu>20</cpu>
<mem>64 GB</mem>
<storage>100 TB</storage>
</resources>
</node>
<node>
<id>UUID12</id>
<name>East Bis-Bis node</name>
<type>BisBis</type>
<ports>
<port>
<id>1</id>
<name>SAP1 port</name>
<port_type>port-sap</port_type>
<vxlan>...</vxlan>
</port>
<port>
<id>0</id>
<name>North port</name>
<port_type>port-abstract</port_type>
<capability>...</capability>
</port>
<port>
<id>2</id>
<name>West port</name>
<port_type>port-abstract</port_type>
<capability>...</capability>
</port>
</ports>
<resources>
<cpu>10</cpu>
<mem>32 GB</mem>
<storage>100 TB</storage>
</resources>
</node>
<node>
<id>UUID13</id>
<name>North Bis-Bis node</name>
<type>BisBis</type>
<ports>
<port>
<id>0</id>
<name>SAP2 port</name>
<port_type>port-sap</port_type>
<vxlan>...</vxlan>
</port>
<port>
<id>1</id>
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<name>East port</name>
<port_type>port-abstract</port_type>
<capability>...</capability>
</port>
<port>
<id>2</id>
<name>West port</name>
<port_type>port-abstract</port_type>
<capability>...</capability>
</port>
</ports>
<resources>
<cpu>20</cpu>
<mem>64 GB</mem>
<storage>1 TB</storage>
</resources>
</node>
</nodes>
<links>
<link>
<id>0</id>
<name>Horizontal link</name>
<src>../../nodes/node[id=UUID11]/ports/port[id=2]</src>
<dst>../../nodes/node[id=UUID12]/ports/port[id=2]</dst>
<resources>
<delay>2 ms</delay>
<bandwidth>10 Gb</bandwidth>
</resources>
</link>
<link>
<id>1</id>
<name>West link</name>
<src>../../nodes/node[id=UUID11]/ports/port[id=1]</src>
<dst>../../nodes/node[id=UUID13]/ports/port[id=2]</dst>
<resources>
<delay>5 ms</delay>
<bandwidth>10 Gb</bandwidth>
</resources>
</link>
<link>
<id>2</id>
<name>East link</name>
<src>../../nodes/node[id=UUID12]/ports/port[id=0]</src>
<dst>../../nodes/node[id=UUID13]/ports/port[id=1]</dst>
<resources>
<delay>2 ms</delay>
<bandwidth>5 Gb</bandwidth>
</resources>
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</link>
</links>
</virtualizer>
Figure 16: 3-node infrastructure report example: xml view
6.2. Simple requests
Figure 17 and Figure 18 show the allocation request for 3 NFs (NF1:
Parental control B.4, NF2: Http Cache 1.2 and NF3: Stateful firewall
C) as instrumented over a BiS-BiS node. It can be seen that the
configuration request contains both the NF placement and the
forwarding overlay definition as a joint request.
+---+ +---+ +---+
|NF1| |NF2| |NF3|
+---+ +---+ +---+
| | | | | |
+-2-3----4-5----6-7--+
--[0-/ \____/ \----|- \ |
| |___________| \-+1]--
| |
| BiS-BiS (UUID11) |
+--------------------+
Figure 17: Simple request of 3 NFs on a single BiS-BiS:
Virtualization view
<virtualizer xmlns="http://fp7-unify.eu/framework/virtualizer">
<id>UUID001</id>
<name>Single node simple request</name>
<nodes>
<node>
<id>UUID11</id>
<NF_instances>
<node>
<id>NF1</id>
<name>first NF</name>
<type>Parental control B.4</type>
<ports>
<port>
<id>2</id>
<name>in</name>
<port_type>port-abstract</port_type>
<capability>...</capability>
</port>
<port>
<id>3</id>
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<name>out</name>
<port_type>port-abstract</port_type>
<capability>...</capability>
</port>
</ports>
</node>
<node>
<id>NF2</id>
<name>cache</name>
<type>Http Cache 1.2</type>
<ports>
<port>
<id>4</id>
<name>in</name>
<port_type>port-abstract</port_type>
<capability>...</capability>
</port>
<port>
<id>5</id>
<name>out</name>
<port_type>port-abstract</port_type>
<capability>...</capability>
</port>
</ports>
</node>
<node>
<id>NF3</id>
<name>firewall</name>
<type>Stateful firewall C</type>
<ports>
<port>
<id>6</id>
<name>in</name>
<port_type>port-abstract</port_type>
<capability>...</capability>
</port>
<port>
<id>7</id>
<name>out</name>
<port_type>port-abstract</port_type>
<capability>...</capability>
</port>
</ports>
</node>
</NF_instances>
<flowtable>
<flowentry>
<port>../../ports/port[id=0]</port>
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<match>*</match>
<action>output:../../NF_instances/node[id=NF1]
/ports/port[id=2]</action>
</flowentry>
<flowentry>
<port>../../NF_instances/node[id=NF1]
/ports/port[id=3]</port>
<match>fr-a</match>
<action>output:../../NF_instances/node[id=NF2]
/ports/port[id=4]</action>
rpcre </flowentry>
<flowentry>
<port>../../NF_instances/node[id=NF1]
/ports/port[id=3]</port>
<match>fr-b</match>
<action>output:../../NF_instances/node[id=NF3]
/ports/port[id=6]</action>
</flowentry>
<flowentry>
<port>../../NF_instances/node[id=NF2]
/ports/port[id=5]</port>
<match>*</match>
<action>output:../../ports/port[id=1]</action>
</flowentry>
<flowentry>
<port>../../NF_instances/node[id=NF3]
/ports/port[id=7]</port>
<match>*</match>
<action>output:../../ports/port[id=1]</action>
</flowentry>
</flowtable>
</node>
</nodes>
</virtualizer>
Figure 18: Simple request of 3 NFs on a single BiS-BiS: xml view
7. IANA Considerations
This memo includes no request to IANA.
8. Security Considerations
TBD
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9. Acknowledgement
The research leading to these results has received funding from the
European Union Seventh Framework Programme (FP7/2007-2013) under
grant agreement no. 619609 - the UNIFY project. The views expressed
here are those of the authors only. The European Commission is not
liable for any use that may be made of the information in this
document.
We would like to thank in particular David Jocha and Janos Elek from
Ericsson for the useful discussions.
10. Informative References
[ETSI-NFV-Arch]
ETSI, "Architectural Framework v1.1.1", Oct 2013,
<http://www.etsi.org/deliver/etsi_gs/
NFV/001_099/002/01.01.01_60/gs_NFV002v010101p.pdf>.
[ETSI-NFV-MANO]
ETSI, "Network Function Virtualization (NFV) Management
and Orchestration V0.6.1 (draft)", Jul. 2014,
<http://docbox.etsi.org/ISG/NFV/Open/Latest_Drafts/
NFV-MAN001v061-%20management%20and%20orchestration.pdf>.
[I-D.ietf-sfc-dc-use-cases]
Surendra, S., Tufail, M., Majee, S., Captari, C., and S.
Homma, "Service Function Chaining Use Cases In Data
Centers", draft-ietf-sfc-dc-use-cases-03 (work in
progress), July 2015.
[I-D.unify-nfvrg-challenges]
Szabo, R., Csaszar, A., Pentikousis, K., Kind, M., Daino,
D., Qiang, Z., and H. Woesner, "Unifying Carrier and Cloud
Networks: Problem Statement and Challenges", draft-unify-
nfvrg-challenges-02 (work in progress), July 2015.
[I-D.zu-nfvrg-elasticity-vnf]
Qiang, Z. and R. Szabo, "Elasticity VNF", draft-zu-nfvrg-
elasticity-vnf-01 (work in progress), March 2015.
Authors' Addresses
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Robert Szabo
Ericsson Research, Hungary
Irinyi Jozsef u. 4-20
Budapest 1117
Hungary
Email: robert.szabo@ericsson.com
URI: http://www.ericsson.com/
Zu Qiang
Ericsson
8400, boul. Decarie
Ville Mont-Royal, QC 8400
Canada
Email: zu.qiang@ericsson.com
URI: http://www.ericsson.com/
Mario Kind
Deutsche Telekom AG
Winterfeldtstr. 21
10781 Berlin
Germany
Email: mario.kind@telekom.de
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