2 This work is licensed under a Creative Commons Attribution 3.0 Unported
5 http://creativecommons.org/licenses/by/3.0/legalcode
7 ==========================================
8 High Priority Traffic Path
9 ==========================================
11 https://wiki.opnfv.org/display/ovsnfv/OVSFV+Requirement+-+High+Priority+Traffic+Path
13 Introduction paragraph -- why are we doing anything? A single paragraph of
14 prose that operators can understand. The title and this first paragraph
15 should be used as the subject line and body of the commit message
18 Some notes about the process:
20 * The aim of this document is first to define the problem we need to solve,
21 and second agree the overall approach to solve that problem.
23 * This is not intended to be extensive documentation for a new feature.
25 * You should aim to get your spec approved before writing your code.
26 While you are free to write prototypes and code before getting your spec
27 approved, its possible that the outcome of the spec review process leads
28 you towards a fundamentally different solution than you first envisaged.
30 * But, API changes are held to a much higher level of scrutiny.
31 As soon as an API change merges, we must assume it could be in production
32 somewhere, and as such, we then need to support that API change forever.
33 To avoid getting that wrong, we do want lots of details about API changes
36 Some notes about using this template:
38 * Your spec should be in ReSTructured text, like this template.
40 * Please wrap text at 79 columns.
42 * Please do not delete any of the sections in this template. If you have
43 nothing to say for a whole section, just write: None
45 * For help with syntax, see http://sphinx-doc.org/rest.html
47 * To test out your formatting, build the docs using sphinx
49 * If you would like to provide a diagram with your spec, ascii diagrams are
50 required. http://asciiflow.com/ is a very nice tool to assist with making
51 ascii diagrams. The reason for this is that the tool used to review specs is
52 based purely on plain text. Plain text will allow review to proceed without
53 having to look at additional files which can not be viewed in gerrit. It
54 will also allow inline feedback on the diagram itself.
59 A detailed description of the problem. What problem is this blueprint
65 What use cases does this address? What impact on actors does this change have?
66 Ensure you are clear about the actors in each use case: Developer, End User,
72 Here is where you cover the change you propose to make in detail. How do you
73 propose to solve this problem?
75 If this is one part of a larger effort make it clear where this piece ends. In
76 other words, what's the scope of this effort?
78 At this point, if you would like to just get feedback on the problem and
79 proposed change, you can stop here and post this for review to get
80 preliminary feedback. If so please say:
81 Posting to get preliminary feedback on the scope of this spec.
86 What other ways could we do this thing? Why aren't we using those? This doesn't
87 have to be a full literature review, but it should demonstrate that thought has
88 been put into why the proposed solution is an appropriate one.
93 Changes which require modifications to the data model often have a wider impact
94 on the system. The community often has strong opinions on how the data model
95 should be evolved, from both a functional and performance perspective. It is
96 therefore important to capture and gain agreement as early as possible on any
97 proposed changes to the data model.
99 Questions which need to be addressed by this section include:
101 * What new data objects and/or database schema changes is this going to
104 User interface impact
105 ---------------------
107 Each user interface that is either added, changed or removed should have the
110 * Specification for the user interface
112 * Example use case including typical examples for both data supplied
113 by the caller and the response
118 Describe any potential security impact on the system. Some of the items to
121 * Does this change touch sensitive data such as tokens, keys, or user data?
123 * Does this change alter the interface in a way that may impact security, such as
124 a new way to access sensitive information?
126 * Does this change involve cryptography or hashing?
128 * Does this change require the use of sudo or any elevated privileges?
130 * Does this change involve using or parsing user-provided data? This could
131 be directly at the API level or indirectly such as changes to a cache layer.
133 * Can this change enable a resource exhaustion attack, such as allowing a
134 single interaction to consume significant server resources?
136 Other end user impact
137 ---------------------
139 Aside from the user interfaces, are there other ways a user will interact with this
145 Describe any potential performance impact on the system, for example
146 how often will new code be called, and is there a major change to the calling
147 pattern of existing code.
149 Examples of things to consider here include:
151 * Will the change include any locking, and if so what considerations are there
154 Other deployer impact
155 ---------------------
157 Discuss things that will affect how you deploy and configure Open vSwitch
158 that have not already been mentioned, such as:
160 * What config options are being added? Should they be more generic than
161 proposed? Are the default values ones which will work well in
164 * Is this a change that takes immediate effect after its merged, or is it
165 something that has to be explicitly enabled?
167 * If this change is a new binary, how would it be deployed?
169 * Please state anything that those doing continuous deployment, or those
170 upgrading from the previous release, need to be aware of. Also describe
171 any plans to deprecate configuration values or features.
176 Discuss things that will affect other developers working on Open vSwitch,
185 Who is leading the writing of the code? Or is this a blueprint where you're
186 throwing it out there to see who picks it up?
188 If more than one person is working on the implementation, please designate the
189 primary author and contact.
200 Work items or tasks -- break the feature up into the things that need to be
201 done to implement it. Those parts might end up being done by different people,
202 but we're mostly trying to understand the timeline for implementation.
208 * If this requires functionality of another project that is not currently used
211 * Does this feature require any new library dependencies or code otherwise not
212 included in Open vSwitch? Or does it depend on a specific version of library?
218 Please discuss the important scenarios needed to test here, as well as
219 specific edge cases we should be ensuring work correctly. For each
220 scenario please specify if this requires specialized hardware.
222 Please discuss how the change will be tested: Open vSwitch unit tests, VSPERF
223 performance tests, Yardstick tests, etc.
225 Is this untestable in gate given current limitations (specific hardware /
226 software configurations available)? If so, are there mitigation plans (3rd
227 party testing, gate enhancements, etc).
233 Which audiences are affected most by this change, and which documentation
234 should be updated because of this change? Don't
235 repeat details discussed above, but reference them here in the context of
236 documentation for multiple audiences. If a config option
237 changes or is deprecated, note here that the documentation needs to be updated
238 to reflect this specification's change.
243 Please add any useful references here. You are not required to have any
244 reference. Moreover, this specification should still make sense when your
245 references are unavailable. Examples of what you could include are:
247 * Links to mailing list or IRC discussions
249 - http://lists.opnfv.org/pipermail/opnfv-tech-discuss/2015-December/007193.html
250 - http://ircbot.wl.linuxfoundation.org/meetings/opnfv-ovsnfv/2016/opnfv-ovsnfv.2016-03-07-13.01.html
252 * Links to relevant research, if appropriate
254 - https://wiki.opnfv.org/download/attachments/5046510/qos_mechanisms.pdf?version=1&modificationDate=1459187636000&api=v2
256 * Related specifications as appropriate
258 * Anything else you feel it is worthwhile to refer to
264 Optional section intended to be used each time the spec
265 is updated to describe new design, API or any database schema
266 updated. Useful to let reader understand what's happened along the
269 .. list-table:: Revisions