12. Network Services Benchmarking (NSB)

12.1. Abstract

This chapter provides an overview of the NSB, a contribution to OPNFV Yardstick from Intel.

12.2. Overview

The goal of NSB is to Extend Yardstick to perform real world VNFs and NFVi Characterization and benchmarking with repeatable and deterministic methods.

The Network Service Benchmarking (NSB) extends the yardstick framework to do VNF characterization and benchmarking in three different execution environments - bare metal i.e. native Linux environment, standalone virtual environment and managed virtualized environment (e.g. Open stack etc.). It also brings in the capability to interact with external traffic generators both hardware & software based for triggering and validating the traffic according to user defined profiles.

NSB extension includes:

  • Generic data models of Network Services, based on ETSI spec ETSI GS NFV-TST 001

  • New Standalone context for VNF testing like SRIOV, OVS, OVS-DPDK etc

  • Generic VNF configuration models and metrics implemented with Python classes

  • Traffic generator features and traffic profiles

    • L1-L3 state-less traffic profiles
    • L4-L7 state-full traffic profiles
    • Tunneling protocol / network overlay support
  • Test case samples

    • Ping
    • Trex
    • vPE,vCGNAT, vFirewall etc - ipv4 throughput, latency etc
  • Traffic generators like Trex, ab/nginx, ixia, iperf etc

  • KPIs for a given use case:

    • System agent support for collecting NFVi KPI. This includes:

      • CPU statistic
      • Memory BW
      • OVS-DPDK Stats
    • Network KPIs, e.g., inpackets, outpackets, thoughput, latency etc

    • VNF KPIs, e.g., packet_in, packet_drop, packet_fwd etc

12.3. Architecture

The Network Service (NS) defines a set of Virtual Network Functions (VNF) connected together using NFV infrastructure.

The Yardstick NSB extension can support multiple VNFs created by different vendors including traffic generators. Every VNF being tested has its own data model. The Network service defines a VNF modelling on base of performed network functionality. The part of the data model is a set of the configuration parameters, number of connection points used and flavor including core and memory amount.

The ETSI defines a Network Service as a set of configurable VNFs working in some NFV Infrastructure connecting each other using Virtual Links available through Connection Points. The ETSI MANO specification defines a set of management entities called Network Service Descriptors (NSD) and VNF Descriptors (VNFD) that define real Network Service. The picture below makes an example how the real Network Operator use-case can map into ETSI Network service definition

Network Service framework performs the necessary test steps. It may involve

  • Interacting with traffic generator and providing the inputs on traffic type / packet structure to generate the required traffic as per the test case. Traffic profiles will be used for this.
  • Executing the commands required for the test procedure and analyses the command output for confirming whether the command got executed correctly or not. E.g. As per the test case, run the traffic for the given time period / wait for the necessary time delay
  • Verify the test result.
  • Validate the traffic flow from SUT
  • Fetch the table / data from SUT and verify the value as per the test case
  • Upload the logs from SUT onto the Test Harness server
  • Read the KPI’s provided by particular VNF

12.3.1. Components of Network Service

  • Models for Network Service benchmarking: The Network Service benchmarking requires the proper modelling approach. The NSB provides models using Python files and defining of NSDs and VNFDs.

The benchmark control application being a part of OPNFV yardstick can call that python models to instantiate and configure the VNFs. Depending on infrastructure type (bare-metal or fully virtualized) that calls could be made directly or using MANO system.

  • Traffic generators in NSB: Any benchmark application requires a set of traffic generator and traffic profiles defining the method in which traffic is generated.

The Network Service benchmarking model extends the Network Service definition with a set of Traffic Generators (TG) that are treated same way as other VNFs being a part of benchmarked network service. Same as other VNFs the traffic generator are instantiated and terminated.

Every traffic generator has own configuration defined as a traffic profile and a set of KPIs supported. The python models for TG is extended by specific calls to listen and generate traffic.

  • The stateless TREX traffic generator: The main traffic generator used as Network Service stimulus is open source TREX tool.

The TREX tool can generate any kind of stateless traffic.

+--------+      +-------+      +--------+
|        |      |       |      |        |
|  Trex  | ---> |  VNF  | ---> |  Trex  |
|        |      |       |      |        |
+--------+      +-------+      +--------+

Supported testcases scenarios:

  • Correlated UDP traffic using TREX traffic generator and replay VNF.

    • using different IMIX configuration like pure voice, pure video traffic etc
    • using different number IP flows like 1 flow, 1K, 16K, 64K, 256K, 1M flows
    • Using different number of rules configured like 1 rule, 1K, 10K rules

For UDP correlated traffic following Key Performance Indicators are collected for every combination of test case parameters:

  • RFC2544 throughput for various loss rate defined (1% is a default)

12.4. Graphical Overview

NSB Testing with yardstick framework facilitate performance testing of various VNFs provided.

+-----------+
|           |                                                     +-----------+
|   vPE     |                                                   ->|TGen Port 0|
| TestCase  |                                                   | +-----------+
|           |                                                   |
+-----------+     +------------------+            +-------+     |
                  |                  | -- API --> |  VNF  | <--->
+-----------+     |     Yardstick    |            +-------+     |
| Test Case | --> |    NSB Testing   |                          |
+-----------+     |                  |                          |
      |           |                  |                          |
      |           +------------------+                          |
+-----------+                                                   | +-----------+
|   Traffic |                                                   ->|TGen Port 1|
|  patterns |                                                     +-----------+
+-----------+

            Figure 1: Network Service - 2 server configuration

12.4.1. VNFs supported for chracterization:

  1. CGNAPT - Carrier Grade Network Address and port Translation

  2. vFW - Virtual Firewall

  3. vACL - Access Control List

  4. Prox - Packet pROcessing eXecution engine:
    • VNF can act as Drop, Basic Forwarding (no touch), L2 Forwarding (change MAC), GRE encap/decap, Load balance based on packet fields, Symmetric load balancing
    • QinQ encap/decap IPv4/IPv6, ARP, QoS, Routing, Unmpls, Policing, ACL
  5. UDP_Replay