]>
Commit | Line | Data |
---|---|---|
bea97716 BP |
1 | OpenFlow 1.1+ support in Open vSwitch |
2 | ===================================== | |
3 | ||
4 | Open vSwitch support for OpenFlow 1.1, 1.2, and 1.3 is a work in | |
5 | progress. This file describes the work still to be done. | |
6 | ||
7 | The Plan | |
8 | -------- | |
9 | ||
10 | OpenFlow version support is not a build-time option. A single build | |
11 | of Open vSwitch must be able to handle all supported versions of | |
12 | OpenFlow. Ideally, even at runtime it should be able to support all | |
13 | protocol versions at the same time on different OpenFlow bridges (and | |
14 | perhaps even on the same bridge). | |
15 | ||
16 | At the same time, it would be a shame to litter the core of the OVS | |
17 | code with lots of ugly code concerned with the details of various | |
18 | OpenFlow protocol versions. | |
19 | ||
20 | The primary approach to compatibility is to abstract most of the | |
21 | details of the differences from the core code, by adding a protocol | |
22 | layer that translates between OF1.x and a slightly higher-level | |
23 | abstract representation. The core of this approach is the many struct | |
24 | ofputil_* structures in lib/ofp-util.h. | |
25 | ||
26 | As a consequence of this approach, OVS cannot use OpenFlow protocol | |
27 | definitions that closely resemble those in the OpenFlow specification, | |
28 | because openflow.h in different versions of the OpenFlow specification | |
29 | defines the same identifier with different values. Instead, | |
30 | openflow-common.h contains definitions that are common to all the | |
31 | specifications and separate protocol version-specific headers contain | |
32 | protocol-specific definitions renamed so as not to conflict, | |
33 | e.g. OFPAT10_ENQUEUE and OFPAT11_ENQUEUE for the OpenFlow 1.0 and 1.1 | |
34 | values for OFPAT_ENQUEUE. Generally, in cases of conflict, the | |
35 | protocol layer will define a more abstract OFPUTIL_* or struct | |
36 | ofputil_*. | |
37 | ||
38 | Here are the current approaches in a few tricky areas: | |
39 | ||
40 | * Port numbering. OpenFlow 1.0 has 16-bit port numbers and later | |
41 | OpenFlow versions have 32-bit port numbers. For now, OVS | |
42 | support for later protocol versions requires all port numbers to | |
43 | fall into the 16-bit range, translating the reserved OFPP_* port | |
44 | numbers. | |
45 | ||
46 | * Actions. OpenFlow 1.0 and later versions have very different | |
47 | ideas of actions. OVS reconciles by translating all the | |
48 | versions' actions (and instructions) to and from a common | |
49 | internal representation. | |
50 | ||
51 | OpenFlow 1.1 | |
52 | ------------ | |
53 | ||
54 | The list of remaining work items for OpenFlow 1.1 is below. It is | |
55 | probably incomplete. | |
56 | ||
4db3f50a | 57 | * OFPT_TABLE_MOD message. This is new in OF1.1, so we need to |
bea97716 BP |
58 | implement it. It should be implemented so that the default OVS |
59 | behavior does not change. | |
4db3f50a SH |
60 | [required for OF1.1 and OF1.2] |
61 | ||
bea97716 | 62 | * MPLS. Simon Horman maintains a patch series that adds this |
ac3d64b1 | 63 | feature. This is partially merged. |
4db3f50a | 64 | [optional for OF1.1+] |
bea97716 | 65 | |
bea97716 BP |
66 | * Match and set double-tagged VLANs (QinQ). This requires kernel |
67 | work for reasonable performance. | |
4db3f50a | 68 | [optional for OF1.1+] |
bea97716 BP |
69 | |
70 | * VLANs tagged with 88a8 Ethertype. This requires kernel work for | |
71 | reasonable performance. | |
4db3f50a | 72 | [required for OF1.1+] |
bea97716 | 73 | |
bea97716 BP |
74 | OpenFlow 1.2 |
75 | ------------ | |
76 | ||
86189a8c GS |
77 | OpenFlow 1.2 support requires OpenFlow 1.1 as a prerequisite. All the |
78 | additional work specific to Openflow 1.2 are complete. (This is based | |
79 | on the change log at the end of the OF1.2 spec. I didn't compare the | |
80 | specs carefully yet.) | |
bea97716 | 81 | |
bea97716 BP |
82 | OpenFlow 1.3 |
83 | ------------ | |
84 | ||
85 | OpenFlow 1.3 support requires OpenFlow 1.2 as a prerequisite, plus the | |
86 | following additional work. (This is based on the change log at the | |
87 | end of the OF1.3 spec, reusing most of the section titles directly. I | |
b2c9b585 | 88 | didn't compare the specs carefully yet.) |
bea97716 BP |
89 | |
90 | * Add support for multipart requests. | |
ff3c2c63 | 91 | Currently we always report OFPBRC_MULTIPART_BUFFER_OVERFLOW. |
4db3f50a | 92 | [optional for OF1.3+] |
bea97716 BP |
93 | |
94 | * Add OFPMP_TABLE_FEATURES statistics. | |
4db3f50a | 95 | [optional for OF1.3+] |
bea97716 BP |
96 | |
97 | * More flexible table miss support. | |
48a5f330 YT |
98 | This requires the following. |
99 | - Change the default table-miss action (in the absense of table-miss | |
100 | entry) from packet_in to drop for OF1.3+. Decide what to do if | |
101 | a switch is configured to support multiple OF versions. | |
4db3f50a | 102 | [required for OF1.3+] |
bea97716 BP |
103 | |
104 | * IPv6 extension header handling support. Fully implementing this | |
105 | requires kernel support. This likely will take some careful and | |
106 | probably time-consuming design work. The actual coding, once | |
107 | that is all done, is probably 2 or 3 days work. | |
4db3f50a | 108 | [optional for OF1.3+] |
bea97716 | 109 | |
e34afc3f BP |
110 | * Per-flow meters. OpenFlow protocol support is now implemented. |
111 | Support for the special OFPM_SLOWPATH and OFPM_CONTROLLER meters | |
112 | is missing. Support for the software switch is under review. | |
4db3f50a | 113 | [optional for OF1.3+] |
bea97716 | 114 | |
4db3f50a SH |
115 | * Auxiliary connections. An implementation in generic code might |
116 | be a week's worth of work. The value of an implementation in | |
117 | generic code is questionable, though, since much of the benefit | |
118 | of axuiliary connections is supposed to be to take advantage of | |
119 | hardware support. (We could make the kernel module somehow | |
120 | send packets across the auxiliary connections directly, for | |
121 | some kind of "hardware" support, if we judged it useful enough.) | |
122 | [optional for OF1.3+] | |
bea97716 | 123 | |
c39f3d73 SH |
124 | * MPLS BoS matching. |
125 | Part of MPLS patchset by Simon Horman. | |
4db3f50a | 126 | [optional for OF1.3+] |
bea97716 | 127 | |
b2c9b585 BP |
128 | * Provider Backbone Bridge tagging. I don't plan to implement |
129 | this (but we'd accept an implementation). | |
4db3f50a | 130 | [optional for OF1.3+] |
bea97716 | 131 | |
c39f3d73 SH |
132 | * Rework tag order. |
133 | Part of MPLS patchset by Simon Horman. | |
4db3f50a | 134 | [required for v1.3+] |
bea97716 | 135 | |
bea97716 BP |
136 | * On-demand flow counters. I think this might be a real |
137 | optimization in some cases for the software switch. | |
4db3f50a SH |
138 | [optional for OF1.3+] |
139 | ||
9fa96468 YT |
140 | ONF OpenFlow Exensions for 1.3.X Pack1 |
141 | -------------------------------------- | |
142 | ||
143 | OpenFlow 1.3 has a bunch of ONF extentions. | |
144 | Many of them are necessary for OpenFlow 1.4 as well. | |
145 | ||
146 | * Flow entry notifications | |
147 | This seems to be modelled after OVS's NXST_FLOW_MONITOR. | |
148 | [EXT-187] | |
149 | [required for OF1.4+] | |
150 | ||
151 | * Role Status | |
152 | [EXT-191] | |
153 | [required for OF1.4+] | |
154 | ||
155 | * Flow entry eviction | |
156 | OVS has flow eviction functionality. | |
157 | table_mod OFPTC_EVICTION, flow_mod 'importance', and | |
158 | table_desc ofp_table_mod_prop_eviction need to be implemented. | |
159 | [EXT-192-e] | |
160 | [optional for OF1.4+] | |
161 | ||
162 | * Vacancy events | |
163 | [EXT-192-v] | |
164 | [optional for OF1.4+] | |
165 | ||
166 | * Bundle | |
167 | Transactional modification. OpenFlow 1.4 requires to support | |
168 | flow_mods and port_mods in a bundle. | |
169 | (Not related to OVS's 'ofbundle' stuff.) | |
170 | [EXT-230] | |
171 | [required for OF1.4+] | |
172 | ||
173 | * Table synchronisation | |
174 | [EXT-232] | |
175 | [optional for OF1.4+] | |
176 | ||
177 | * Group notifications | |
178 | [EXT-235] | |
179 | [optional for OF1.4+] | |
180 | ||
181 | * Bad flow entry priority error | |
182 | Probably not so useful to the software switch. | |
183 | [EXT-236] | |
184 | [optional for OF1.4+] | |
185 | ||
186 | * Set async config error | |
187 | [EXT-237] | |
188 | [optional for OF1.4+] | |
189 | ||
190 | * PBB UCA header field | |
191 | [EXT-256] | |
192 | [optional for OF1.4+] | |
193 | ||
194 | * Duplicate instruction error | |
195 | We already have ONFBIC_DUP_INSTRUCTION. | |
196 | [EXT-260] | |
197 | [required for OF1.4+] | |
198 | ||
199 | * Multipart timeout error | |
200 | [EXT-264] | |
201 | [required for OF1.4+] | |
202 | ||
203 | OpenFlow 1.4 | |
204 | ------------ | |
205 | ||
206 | * More extensible wire protocol | |
207 | Many on-wire structures got TLVs. | |
208 | [EXT-262] | |
209 | [required for OF1.4+] | |
210 | ||
211 | * More descriptive reasons for packet-in | |
212 | Distinguish OFPR_APPLY_ACTION, OFPR_ACTION_SET, OFPR_GROUP, | |
213 | OFPR_PACKET_OUT. NO_MATCH was renamed to OFPR_TABLE_MISS. | |
214 | [EXT-136] | |
215 | [required for OF1.4+] | |
216 | ||
217 | * Optical port properties | |
218 | [EXT-154] | |
219 | [optional for OF1.4+] | |
220 | ||
221 | * Flow-removed reason for meter delete | |
222 | Report flow removal due to meter deletion with OFPRR_METER_DELETE. | |
223 | [EXT-261] | |
224 | [optional for OF1.4+] | |
225 | ||
226 | * Meter notifications | |
227 | [EXT-235] | |
228 | [optional for OF1.4+] | |
bea97716 | 229 | |
70d0aed3 BP |
230 | General |
231 | ----- | |
232 | ||
233 | * ovs-ofctl(8) often lists as Nicira extensions features that | |
234 | later OpenFlow versions support in standard ways. | |
235 | ||
bea97716 BP |
236 | How to contribute |
237 | ----------------- | |
238 | ||
239 | If you plan to contribute code for a feature, please let everyone know | |
240 | on ovs-dev before you start work. This will help avoid duplicating | |
241 | work. | |
242 | ||
243 | Please consider the following: | |
244 | ||
245 | * Testing. Please test your code. | |
246 | ||
247 | * Unit tests. Please consider writing some. The tests directory | |
248 | has many examples that you can use as a starting point. | |
249 | ||
250 | * ovs-ofctl. If you add a feature that is useful for some | |
251 | ovs-ofctl command then you should add support for it there. | |
252 | ||
253 | * Documentation. If you add a user-visible feature, then you | |
254 | should document it in the appropriate manpage and mention it in | |
255 | NEWS as well. | |
256 | ||
257 | * Coding style (see the CodingStyle file at the top of the source | |
258 | tree). | |
259 | ||
260 | * The patch submission guidelines (see SubmittingPatches). I | |
b2c9b585 | 261 | recommend using "git send-email", which automatically follows a |
bea97716 BP |
262 | lot of those guidelines. |
263 | ||
264 | Bug Reporting | |
265 | ------------- | |
266 | ||
267 | Please report problems to bugs@openvswitch.org. |