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doc: Convert OPENFLOW-1.1+ to rST

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Rename it to OPENFLOW.

Signed-off-by: Stephen Finucane <stephen@that.guru>
Signed-off-by: Russell Bryant <russell@ovn.org>
This commit is contained in:
Stephen Finucane
2016-10-18 21:03:42 +01:00
committed by Russell Bryant
parent 255efa729d
commit a5788894a7
4 changed files with 418 additions and 320 deletions
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4
FAQ.md
View File

@@ -1609,7 +1609,7 @@ A: The following table lists the versions of OpenFlow supported by
(Open vSwitch 2.2 had an experimental implementation of OpenFlow
1.4 that could cause crashes. We don't recommend enabling it.)
[OPENFLOW-1.1+.md] in the Open vSwitch source tree tracks support for
[OPENFLOW.rst] in the Open vSwitch source tree tracks support for
OpenFlow 1.1 and later features. When support for OpenFlow 1.4 and
1.5 is solidly implemented, Open vSwitch will enable those version
by default.
@@ -2152,7 +2152,7 @@ http://openvswitch.org/
[PORTING.rst]:PORTING.rst
[WHY-OVS.rst]:WHY-OVS.rst
[INSTALL.rst]:INSTALL.rst
[OPENFLOW-1.1+.md]:OPENFLOW-1.1+.md
[OPENFLOW.rst]:OPENFLOW.rst
[INSTALL.DPDK.rst]:INSTALL.DPDK.rst
[Tutorial.md]:tutorial/Tutorial.md
[release-process.md]:Documentation/release-process.md

2
Makefile.am
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@@ -88,7 +88,7 @@ docs = \
INSTALL.Windows.rst \
IntegrationGuide.rst \
MAINTAINERS.rst \
OPENFLOW-1.1+.md \
OPENFLOW.rst \
PORTING.rst \
README.rst \
README-lisp.rst \

317
OPENFLOW-1.1+.md
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@@ -1,317 +0,0 @@
OpenFlow 1.1+ support in Open vSwitch
=====================================
Open vSwitch support for OpenFlow 1.1 and beyond is a work in
progress. This file describes the work still to be done.
The Plan
--------
OpenFlow version support is not a build-time option. A single build
of Open vSwitch must be able to handle all supported versions of
OpenFlow. Ideally, even at runtime it should be able to support all
protocol versions at the same time on different OpenFlow bridges (and
perhaps even on the same bridge).
At the same time, it would be a shame to litter the core of the OVS
code with lots of ugly code concerned with the details of various
OpenFlow protocol versions.
The primary approach to compatibility is to abstract most of the
details of the differences from the core code, by adding a protocol
layer that translates between OF1.x and a slightly higher-level
abstract representation. The core of this approach is the many struct
ofputil_* structures in include/openvswitch/ofp-util.h.
As a consequence of this approach, OVS cannot use OpenFlow protocol
definitions that closely resemble those in the OpenFlow specification,
because openflow.h in different versions of the OpenFlow specification
defines the same identifier with different values. Instead,
openflow-common.h contains definitions that are common to all the
specifications and separate protocol version-specific headers contain
protocol-specific definitions renamed so as not to conflict,
e.g. OFPAT10_ENQUEUE and OFPAT11_ENQUEUE for the OpenFlow 1.0 and 1.1
values for OFPAT_ENQUEUE. Generally, in cases of conflict, the
protocol layer will define a more abstract OFPUTIL_* or struct
ofputil_*.
Here are the current approaches in a few tricky areas:
* Port numbering. OpenFlow 1.0 has 16-bit port numbers and later
OpenFlow versions have 32-bit port numbers. For now, OVS
support for later protocol versions requires all port numbers to
fall into the 16-bit range, translating the reserved OFPP_* port
numbers.
* Actions. OpenFlow 1.0 and later versions have very different
ideas of actions. OVS reconciles by translating all the
versions' actions (and instructions) to and from a common
internal representation.
OpenFlow 1.1
------------
The list of remaining work items for OpenFlow 1.1 is below. It is
probably incomplete.
* Match and set double-tagged VLANs (QinQ). This requires kernel
work for reasonable performance.
[optional for OF1.1+]
* VLANs tagged with 88a8 Ethertype. This requires kernel work for
reasonable performance.
[required for OF1.1+]
OpenFlow 1.2
------------
OpenFlow 1.2 support requires OpenFlow 1.1 as a prerequisite. All the
additional work specific to Openflow 1.2 are complete. (This is based
on the change log at the end of the OF1.2 spec. I didn't compare the
specs carefully yet.)
OpenFlow 1.3
------------
OpenFlow 1.3 support requires OpenFlow 1.2 as a prerequisite, plus the
following additional work. (This is based on the change log at the
end of the OF1.3 spec, reusing most of the section titles directly. I
didn't compare the specs carefully yet.)
* Add support for multipart requests.
Currently we always report OFPBRC_MULTIPART_BUFFER_OVERFLOW.
[optional for OF1.3+]
* IPv6 extension header handling support. Fully implementing this
requires kernel support. This likely will take some careful and
probably time-consuming design work. The actual coding, once
that is all done, is probably 2 or 3 days work.
[optional for OF1.3+]
* Per-flow meters. OpenFlow protocol support is now implemented.
Support for the special OFPM_SLOWPATH and OFPM_CONTROLLER meters
is missing. Support for the software switch is under review.
[optional for OF1.3+]
* Auxiliary connections. An implementation in generic code might
be a week's worth of work. The value of an implementation in
generic code is questionable, though, since much of the benefit
of axuiliary connections is supposed to be to take advantage of
hardware support. (We could make the kernel module somehow
send packets across the auxiliary connections directly, for
some kind of "hardware" support, if we judged it useful enough.)
[optional for OF1.3+]
* Provider Backbone Bridge tagging. I don't plan to implement
this (but we'd accept an implementation).
[optional for OF1.3+]
* On-demand flow counters. I think this might be a real
optimization in some cases for the software switch.
[optional for OF1.3+]
OpenFlow 1.4 & ONF Extensions for 1.3.X Pack1
---------------------------------------------
The following features are both defined as a set of ONF Extensions
for 1.3 and integrated in 1.4.
When defined as an ONF Extension for 1.3, the feature is using the
Experimenter mechanism with the ONF Experimenter ID.
When defined integrated in 1.4, the feature use the standard OpenFlow
structures (for example defined in openflow-1.4.h).
The two definitions for each feature are independant and can exist in
parallel in OVS.
* Flow entry notifications
This seems to be modelled after OVS's NXST_FLOW_MONITOR.
(Simon Horman is working on this.)
[EXT-187]
[optional for OF1.4+]
* Role Status
Already implemented as a 1.4 feature.
[EXT-191]
[required for OF1.4+]
* Flow entry eviction
OVS has flow eviction functionality.
table_mod OFPTC_EVICTION, flow_mod 'importance', and
table_desc ofp_table_mod_prop_eviction need to be implemented.
[EXT-192-e]
[optional for OF1.4+]
* Vacancy events
[EXT-192-v]
[optional for OF1.4+]
* Bundle
Transactional modification. OpenFlow 1.4 requires to support
flow_mods and port_mods in a bundle if bundle is supported.
(Not related to OVS's 'ofbundle' stuff.)
Implemented as an OpenFlow 1.4 feature. Only flow_mods and
port_mods are supported in a bundle. If the bundle includes port
mods, it may not specify the OFPBF_ATOMIC flag. Nevertheless,
port mods and flow mods in a bundle are always applied in order
and consecutive flow mods between port mods are made available to
lookups atomically.
[EXT-230]
[optional for OF1.4+]
* Table synchronisation
Probably not so useful to the software switch.
[EXT-232]
[optional for OF1.4+]
* Group and Meter change notifications
[EXT-235]
[optional for OF1.4+]
* Bad flow entry priority error
Probably not so useful to the software switch.
[EXT-236]
[optional for OF1.4+]
* Set async config error
[EXT-237]
[optional for OF1.4+]
* PBB UCA header field
See comment on Provider Backbone Bridge in section about OpenFlow 1.3.
[EXT-256]
[optional for OF1.4+]
* Multipart timeout error
[EXT-264]
[required for OF1.4+]
OpenFlow 1.4 only
-----------------
Those features are those only available in OpenFlow 1.4, other
OpenFlow 1.4 features are listed in the previous section.
* More extensible wire protocol
Many on-wire structures got TLVs.
All required features are now supported.
Remaining optional: table desc, table-status
[EXT-262]
[required for OF1.4+]
* More descriptive reasons for packet-in
Distinguish OFPR_APPLY_ACTION, OFPR_ACTION_SET, OFPR_GROUP,
OFPR_PACKET_OUT. NO_MATCH was renamed to OFPR_TABLE_MISS.
(OFPR_ACTION_SET and OFPR_GROUP are now supported)
[EXT-136]
[required for OF1.4+]
* Optical port properties
[EXT-154]
[optional for OF1.4+]
OpenFlow 1.5 & ONF Extensions for 1.3.X Pack2
---------------------------------------------
The following features are both defined as a set of ONF Extensions for
1.3 and integrated in 1.5. Note that this list is not definitive as
those are not yet published.
When defined as an ONF Extension for 1.3, the feature is using the
Experimenter mechanism with the ONF Experimenter ID.
When defined integrated in 1.5, the feature use the standard OpenFlow
structures (for example defined in openflow-1.5.h).
The two definitions for each feature are independant and can exist in
parallel in OVS.
* Time scheduled bundles
[EXT-340]
[optional for OF1.5+]
OpenFlow 1.5 only
-----------------
Those features are those only available in OpenFlow 1.5, other
OpenFlow 1.5 features are listed in the previous section.
Note that this list is not definitive as OpenFlow 1.5 is not yet
published.
* Egress Tables
[EXT-306]
[optional for OF1.5+]
* Packet Type aware pipeline
Prototype for OVS was done during specification.
[EXT-112]
[optional for OF1.5+]
* Extensible Flow Entry Statistics
[EXT-334]
[required for OF1.5+]
* Flow Entry Statistics Trigger
[EXT-335]
[optional for OF1.5+]
* Controller connection status
Prototype for OVS was done during specification.
[EXT-454]
[optional for OF1.5+]
* Meter action
[EXT-379]
[required for OF1.5+ if metering is supported]
* Enable setting all pipeline fields in packet-out
Prototype for OVS was done during specification.
[EXT-427]
[required for OF1.5+]
* Port properties for pipeline fields
Prototype for OVS was done during specification.
[EXT-388]
[optional for OF1.5+]
* Port property for recirculation
Prototype for OVS was done during specification.
[EXT-399]
[optional for OF1.5+]
General
-----
* ovs-ofctl(8) often lists as Nicira extensions features that
later OpenFlow versions support in standard ways.
How to contribute
-----------------
If you plan to contribute code for a feature, please let everyone know
on ovs-dev before you start work. This will help avoid duplicating
work.
Please consider the following:
* Testing. Please test your code.
* Unit tests. Please consider writing some. The tests directory
has many examples that you can use as a starting point.
* ovs-ofctl. If you add a feature that is useful for some
ovs-ofctl command then you should add support for it there.
* Documentation. If you add a user-visible feature, then you
should document it in the appropriate manpage and mention it in
NEWS as well.
* Coding style (see the [CodingStyle] file at the top of the
source tree).
* The patch submission guidelines (see [CONTRIBUTING.rst]). I
recommend using "git send-email", which automatically follows a
lot of those guidelines.
Bug Reporting
-------------
Please report problems to bugs@openvswitch.org.
[CONTRIBUTING.md]: CONTRIBUTING.md
[CodingStyle.rst]: CodingStyle.rst

415
OPENFLOW.rst Normal file
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@@ -0,0 +1,415 @@
..
Licensed under the Apache License, Version 2.0 (the "License"); you may
not use this file except in compliance with the License. You may obtain
a copy of the License at
http://www.apache.org/licenses/LICENSE-2.0
Unless required by applicable law or agreed to in writing, software
distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
License for the specific language governing permissions and limitations
under the License.
Convention for heading levels in Open vSwitch documentation:
======= Heading 0 (reserved for the title in a document)
------- Heading 1
~~~~~~~ Heading 2
+++++++ Heading 3
''''''' Heading 4
Avoid deeper levels because they do not render well.
================================
OpenFlow Support in Open vSwitch
================================
Open vSwitch support for OpenFlow 1.1 and beyond is a work in progress. This
file describes the work still to be done.
The Plan
--------
OpenFlow version support is not a build-time option. A single build of Open
vSwitch must be able to handle all supported versions of OpenFlow. Ideally,
even at runtime it should be able to support all protocol versions at the same
time on different OpenFlow bridges (and perhaps even on the same bridge).
At the same time, it would be a shame to litter the core of the OVS code with
lots of ugly code concerned with the details of various OpenFlow protocol
versions.
The primary approach to compatibility is to abstract most of the details of the
differences from the core code, by adding a protocol layer that translates
between OF1.x and a slightly higher-level abstract representation. The core of
this approach is the many ``struct ofputil_*`` structures in
``include/openvswitch/ofp-util.h``.
As a consequence of this approach, OVS cannot use OpenFlow protocol definitions
that closely resemble those in the OpenFlow specification, because
``openflow.h`` in different versions of the OpenFlow specification defines the
same identifier with different values. Instead, ``openflow-common.h`` contains
definitions that are common to all the specifications and separate protocol
version-specific headers contain protocol-specific definitions renamed so as
not to conflict, e.g. ``OFPAT10_ENQUEUE`` and ``OFPAT11_ENQUEUE`` for the
OpenFlow 1.0 and 1.1 values for ``OFPAT_ENQUEUE``. Generally, in cases of
conflict, the protocol layer will define a more abstract ``OFPUTIL_*`` or
struct ``ofputil_*``.
Here are the current approaches in a few tricky areas:
* Port numbering.
OpenFlow 1.0 has 16-bit port numbers and later OpenFlow versions have 32-bit
port numbers. For now, OVS support for later protocol versions requires all
port numbers to fall into the 16-bit range, translating the reserved
``OFPP_*`` port numbers.
* Actions.
OpenFlow 1.0 and later versions have very different ideas of actions. OVS
reconciles by translating all the versions' actions (and instructions) to and
from a common internal representation.
OpenFlow 1.1
------------
The list of remaining work items for OpenFlow 1.1 is below. It is probably
incomplete.
* Match and set double-tagged VLANs (QinQ).
This requires kernel work for reasonable performance.
(optional for OF1.1+)
* VLANs tagged with 88a8 Ethertype.
This requires kernel work for reasonable performance.
(required for OF1.1+)
OpenFlow 1.2
------------
OpenFlow 1.2 support requires OpenFlow 1.1 as a prerequisite. All the
additional work specific to Openflow 1.2 are complete. (This is based on the
change log at the end of the OF1.2 spec. I didn't compare the specs carefully
yet.)
OpenFlow 1.3
------------
OpenFlow 1.3 support requires OpenFlow 1.2 as a prerequisite, plus the
following additional work. (This is based on the change log at the end of the
OF1.3 spec, reusing most of the section titles directly. I didn't compare the
specs carefully yet.)
* Add support for multipart requests.
Currently we always report ``OFPBRC_MULTIPART_BUFFER_OVERFLOW``.
(optional for OF1.3+)
* IPv6 extension header handling support.
Fully implementing this requires kernel support. This likely will take some
careful and probably time-consuming design work. The actual coding, once
that is all done, is probably 2 or 3 days work.
(optional for OF1.3+)
* Per-flow meters.
OpenFlow protocol support is now implemented. Support for the special
``OFPM_SLOWPATH`` and ``OFPM_CONTROLLER`` meters is missing. Support for
the software switch is under review.
(optional for OF1.3+)
* Auxiliary connections.
An implementation in generic code might be a week's worth of work. The value
of an implementation in generic code is questionable, though, since much of
the benefit of axuiliary connections is supposed to be to take advantage of
hardware support. (We could make the kernel module somehow send packets
across the auxiliary connections directly, for some kind of "hardware"
support, if we judged it useful enough.)
(optional for OF1.3+)
* Provider Backbone Bridge tagging.
I don't plan to implement this (but we'd accept an implementation).
(optional for OF1.3+)
* On-demand flow counters.
I think this might be a real optimization in some cases for the software
switch.
(optional for OF1.3+)
OpenFlow 1.4 & ONF Extensions for 1.3.X Pack1
---------------------------------------------
The following features are both defined as a set of ONF Extensions for 1.3 and
integrated in 1.4.
When defined as an ONF Extension for 1.3, the feature is using the Experimenter
mechanism with the ONF Experimenter ID.
When defined integrated in 1.4, the feature use the standard OpenFlow
structures (for example defined in openflow-1.4.h).
The two definitions for each feature are independant and can exist in parallel
in OVS.
* Flow entry notifications
This seems to be modelled after OVS's NXST_FLOW_MONITOR. (Simon Horman is
working on this.)
(EXT-187)
(optional for OF1.4+)
* Role Status
Already implemented as a 1.4 feature.
(EXT-191)
(required for OF1.4+)
* Flow entry eviction
OVS has flow eviction functionality. ``table_mod OFPTC_EVICTION``,
``flow_mod 'importance'``, and ``table_desc ofp_table_mod_prop_eviction``
need to be implemented.
(EXT-192-e)
(optional for OF1.4+)
* Vacancy events
(EXT-192-v)
(optional for OF1.4+)
* Bundle
Transactional modification. OpenFlow 1.4 requires to support
``flow_mods`` and ``port_mods`` in a bundle if bundle is supported.
(Not related to OVS's 'ofbundle' stuff.)
Implemented as an OpenFlow 1.4 feature. Only flow_mods and port_mods are
supported in a bundle. If the bundle includes port mods, it may not specify
the ``OFPBF_ATOMIC`` flag. Nevertheless, port mods and flow mods in a bundle
are always applied in order and consecutive flow mods between port mods are
made available to lookups atomically.
(EXT-230)
(optional for OF1.4+)
* Table synchronisation
Probably not so useful to the software switch.
(EXT-232)
(optional for OF1.4+)
* Group and Meter change notifications
(EXT-235)
(optional for OF1.4+)
* Bad flow entry priority error
Probably not so useful to the software switch.
(EXT-236)
(optional for OF1.4+)
* Set async config error
(EXT-237)
(optional for OF1.4+)
* PBB UCA header field
See comment on Provider Backbone Bridge in section about OpenFlow 1.3.
(EXT-256)
(optional for OF1.4+)
* Multipart timeout error
(EXT-264)
(required for OF1.4+)
OpenFlow 1.4 only
-----------------
Those features are those only available in OpenFlow 1.4, other OpenFlow 1.4
features are listed in the previous section.
* More extensible wire protocol
Many on-wire structures got TLVs.
All required features are now supported.
Remaining optional: table desc, table-status
(EXT-262)
(required for OF1.4+)
* More descriptive reasons for packet-in
Distinguish ``OFPR_APPLY_ACTION``, ``OFPR_ACTION_SET``, ``OFPR_GROUP``,
``OFPR_PACKET_OUT``. ``NO_MATCH`` was renamed to ``OFPR_TABLE_MISS``.
(OFPR_ACTION_SET and OFPR_GROUP are now supported)
(EXT-136)
(required for OF1.4+)
* Optical port properties
(EXT-154)
(optional for OF1.4+)
OpenFlow 1.5 & ONF Extensions for 1.3.X Pack2
---------------------------------------------
The following features are both defined as a set of ONF Extensions for 1.3 and
integrated in 1.5. Note that this list is not definitive as those are not yet
published.
When defined as an ONF Extension for 1.3, the feature is using the Experimenter
mechanism with the ONF Experimenter ID. When defined integrated in 1.5, the
feature use the standard OpenFlow structures (for example defined in
openflow-1.5.h).
The two definitions for each feature are independant and can exist in parallel
in OVS.
* Time scheduled bundles
(EXT-340)
(optional for OF1.5+)
OpenFlow 1.5 only
-----------------
Those features are those only available in OpenFlow 1.5, other OpenFlow 1.5
features are listed in the previous section. Note that this list is not
definitive as OpenFlow 1.5 is not yet published.
* Egress Tables
(EXT-306)
(optional for OF1.5+)
* Packet Type aware pipeline
Prototype for OVS was done during specification.
(EXT-112)
(optional for OF1.5+)
* Extensible Flow Entry Statistics
(EXT-334)
(required for OF1.5+)
* Flow Entry Statistics Trigger
(EXT-335)
(optional for OF1.5+)
* Controller connection status
Prototype for OVS was done during specification.
(EXT-454)
(optional for OF1.5+)
* Meter action
(EXT-379)
(required for OF1.5+ if metering is supported)
* Enable setting all pipeline fields in packet-out
Prototype for OVS was done during specification.
(EXT-427)
(required for OF1.5+)
* Port properties for pipeline fields
Prototype for OVS was done during specification.
(EXT-388)
(optional for OF1.5+)
* Port property for recirculation
Prototype for OVS was done during specification.
(EXT-399)
(optional for OF1.5+)
General
-------
* ovs-ofctl(8) often lists as Nicira extensions features that later OpenFlow
versions support in standard ways.
How to contribute
-----------------
If you plan to contribute code for a feature, please let everyone know on
ovs-dev before you start work. This will help avoid duplicating work.
Please consider the following:
* Testing. Please test your code.
* Unit tests. Please consider writing some. The tests directory has many
examples that you can use as a starting point.
* ovs-ofctl. If you add a feature that is useful for some ovs-ofctl command
then you should add support for it there.
* Documentation. If you add a user-visible feature, then you should document
it in the appropriate manpage and mention it in NEWS as well.
* Coding style (see the `coding style guide <CodingStyle.rst>`__ file at the top
of the source tree).
* The `patch submission guidelines <CONTRIBUTING.rst>`__. I recommend using
"git send-email", which automatically follows a lot of those guidelines.