1 .. This work is licensed under a Creative Commons Attribution 4.0 International License.
2 .. http://creativecommons.org/licenses/by/4.0
3 .. (c) OPNFV, Intel Corporation, AT&T and others.
5 ===================================
6 Traffic Generator Integration Guide
7 ===================================
12 This document is intended to aid those who want to integrate new traffic
13 generator into the vsperf code. It is expected, that reader has already
14 read generic part of :ref:`vsperf-design`.
16 Let us create a sample traffic generator called **sample_tg**, step by step.
18 Step 1 - create a directory
19 ===========================
21 Implementation of trafficgens is located at tools/pkt_gen/ directory,
22 where every implementation has its dedicated sub-directory. It is
23 required to create a new directory for new traffic generator
28 .. code-block:: console
30 $ mkdir tools/pkt_gen/sample_tg
32 Step 2 - create a trafficgen module
33 ===================================
35 Every trafficgen class must inherit from generic **ITrafficGenerator**
36 interface class. VSPERF during its initialization scans content of pkt_gen
37 directory for all python modules, that inherit from **ITrafficGenerator**. These
38 modules are automatically added into the list of supported traffic generators.
42 Let us create a draft of tools/pkt_gen/sample_tg/sample_tg.py module.
44 .. code-block:: python
46 from tools.pkt_gen import trafficgen
48 class SampleTG(trafficgen.ITrafficGenerator):
50 A sample traffic generator implementation
54 VSPERF is immediately aware of the new class:
56 .. code-block:: console
58 $ ./vsperf --list-trafficgen
60 Output should look like:
62 .. code-block:: console
64 Classes derived from: ITrafficGenerator
67 * Dummy: A dummy traffic generator whose data is generated by the user.
69 * IxNet: A wrapper around IXIA IxNetwork applications.
71 * Ixia: A wrapper around the IXIA traffic generator.
73 * Moongen: Moongen Traffic generator wrapper.
75 * TestCenter: Spirent TestCenter
77 * Trex: Trex Traffic generator wrapper.
79 * Xena: Xena Traffic generator wrapper class
82 Step 3 - configuration
83 ======================
85 All configuration values, required for correct traffic generator function, are passed
86 from VSPERF to the traffic generator in a dictionary. Default values shared among
87 all traffic generators are defined in **conf/03_traffic.conf** within **TRAFFIC**
88 dictionary. Default values are loaded by **ITrafficGenerator** interface class
89 automatically, so it is not needed to load them explicitly. In case that there are
90 any traffic generator specific default values, then they should be set within class
91 specific **__init__** function.
93 VSPERF passes test specific configuration within **traffic** dictionary to every
94 start and send function. So implementation of these functions must ensure,
95 that default values are updated with the testcase specific values. Proper merge
96 of values is assured by call of **merge_spec** function from **conf** module.
98 Example of **merge_spec** usage in **tools/pkt_gen/sample_tg/sample_tg.py** module:
100 .. code-block:: python
102 from conf import merge_spec
104 def start_rfc2544_throughput(self, traffic=None, duration=30):
106 self._params['traffic'] = self.traffic_defaults.copy()
108 self._params['traffic'] = merge_spec(
109 self._params['traffic'], traffic)
112 Step 4 - generic functions
113 ==========================
115 There are some generic functions, which every traffic generator should provide.
116 Although these functions are mainly optional, at least empty implementation must
117 be provided. This is required, so that developer is explicitly aware of these
120 The **connect** function is called from the traffic generator controller from its
121 **__enter__** method. This function should assure proper connection initialization
122 between DUT and traffic generator. In case, that such implementation is not needed,
123 empty implementation is required.
125 The **disconnect** function should perform clean up of any connection specific
126 actions called from the **connect** function.
128 Example in **tools/pkt_gen/sample_tg/sample_tg.py** module:
130 .. code-block:: python
135 def disconnect(self):
138 .. _step-5-supported-traffic-types:
140 Step 5 - supported traffic types
141 ================================
143 Currently VSPERF supports three different types of tests for traffic generators,
144 these are identified in vsperf through the traffic type, which include:
146 * RFC2544 throughput - Send fixed size packets at different rates, using
147 traffic configuration, until minimum rate at which no packet loss is
148 detected is found. Methods with its implementation have suffix
149 **_rfc2544_throughput**.
151 * RFC2544 back2back - Send fixed size packets at a fixed rate, using traffic
152 configuration, for specified time interval. Methods with its
153 implementation have suffix **_rfc2544_back2back**.
155 * continuous flow - Send fixed size packets at given framerate, using traffic
156 configuration, for specified time interval. Methods with its
157 implementation have suffix **_cont_traffic**.
159 In general, both synchronous and asynchronous interfaces must be implemented
160 for each traffic type. Synchronous functions start with prefix **send_**.
161 Asynchronous with prefixes **start_** and **wait_** in case of throughput
162 and back2back and **start_** and **stop_** in case of continuous traffic type.
164 Example of synchronous interfaces:
166 .. code-block:: python
168 def send_rfc2544_throughput(self, traffic=None, tests=1, duration=20,
170 def send_rfc2544_back2back(self, traffic=None, tests=1, duration=20,
172 def send_cont_traffic(self, traffic=None, duration=20):
174 Example of asynchronous interfaces:
176 .. code-block:: python
178 def start_rfc2544_throughput(self, traffic=None, tests=1, duration=20,
180 def wait_rfc2544_throughput(self):
182 def start_rfc2544_back2back(self, traffic=None, tests=1, duration=20,
184 def wait_rfc2544_back2back(self):
186 def start_cont_traffic(self, traffic=None, duration=20):
187 def stop_cont_traffic(self):
189 Description of parameters used by **send**, **start**, **wait** and **stop**
192 * param **traffic**: A dictionary with detailed definition of traffic
193 pattern. It contains following parameters to be implemented by
196 Note: Traffic dictionary has also virtual switch related parameters,
197 which are not listed below.
199 Note: There are parameters specific to testing of tunnelling protocols,
200 which are discussed in detail at :ref:`integration-tests` userguide.
202 Note: A detailed description of the ``TRAFFIC`` dictionary can be found at
203 :ref:`configuration-of-traffic-dictionary`.
205 * param **traffic_type**: One of the supported traffic types,
206 e.g. **rfc2544_throughput**, **rfc2544_continuous**,
207 **rfc2544_back2back** or **burst**.
208 * param **bidir**: Specifies if generated traffic will be full-duplex
209 (true) or half-duplex (false).
210 * param **frame_rate**: Defines desired percentage of frame
211 rate used during continuous stream tests.
212 * param **burst_size**: Defines a number of frames in the single burst,
213 which is sent by burst traffic type. Burst size is applied for each
214 direction, i.e. the total number of tx frames will be 2*burst_size
215 in case of bidirectional traffic.
216 * param **multistream**: Defines number of flows simulated by traffic
217 generator. Value 0 disables MultiStream feature.
218 * param **stream_type**: Stream Type defines ISO OSI network layer
219 used for simulation of multiple streams.
222 * **L2** - iteration of destination MAC address
223 * **L3** - iteration of destination IP address
224 * **L4** - iteration of destination port of selected transport protocol
226 * param **l2**: A dictionary with data link layer details, e.g. **srcmac**,
227 **dstmac** and **framesize**.
228 * param **l3**: A dictionary with network layer details, e.g. **srcip**,
229 **dstip**, **proto** and l3 on/off switch **enabled**.
230 * param **l4**: A dictionary with transport layer details, e.g. **srcport**,
231 **dstport** and l4 on/off switch **enabled**.
232 * param **vlan**: A dictionary with vlan specific parameters,
233 e.g. **priority**, **cfi**, **id** and vlan on/off switch **enabled**.
234 * param **scapy**: A dictionary with definition of the frame content for both traffic
235 directions. The frame content is defined by a SCAPY notation.
237 * param **tests**: Number of times the test is executed.
238 * param **duration**: Duration of continuous test or per iteration duration
239 in case of RFC2544 throughput or back2back traffic types.
240 * param **lossrate**: Acceptable lossrate percentage.
242 Step 6 - passing back results
243 =============================
245 It is expected that methods **send**, **wait** and **stop** will return
246 values measured by traffic generator within a dictionary. Dictionary keys
247 are defined in **ResultsConstants** implemented in
248 **core/results/results_constants.py**. Please check sections for RFC2544
249 Throughput & Continuous and for Back2Back. The same key names should
250 be used by all traffic generator implementations.