About Data Traffic
With the Data Traffic option, you can simultaneously test the control plane and bearer plane capabilities of an SUT. You can simply verify packet data connectivity or load the bearer plane with continuous traffic. When you use continuous data, you can specify the amount of bandwidth consumed and the protocols used. Data Traffic is available in all nodal test cases that emulate mobile nodes.
The data model is defined as part of the test case with the Data Traffic pane on the General tab. In addition to emulating MNs, the test system emulates application servers with Network Host nodes (Correspondent Nodes in MIPv6 testing). You define the boundaries of the traffic — when the traffic begins, error injection, and fragmentation size — and the protocol type, the data rate, and the packets sent. Combining data traffic with a test activity allows you to define a test that requires the SUT to simultaneously handle a mix of control and data activities, completing your real-world model.
A Data Message Flow (DMF) contains the data model definition, including the protocol, the rate used for data traffic, and the messages exchanged between the MN and the Network Host. DMFs can be saved to the Test Library and included in any data-capable test case. A single execution of a DMF is referred to as a transaction. A DMF can also be embedded in another DMF to repeat a transaction a number of times, to combine different protocols in one message flow, or when the protocol uses a different connection for data transfer as does FTP. The embedded DMF is called the subflow and the parent DMF is called the mainflow.
Traffic Capacity
The capacity of the bearer plane traffic generated by each test server depends on the application and traffic model. In the default configuration, one test case emulates both ends of the data connection, the MN and the Network Host, consuming two interfaces and the processing power required for sending and receiving all of the traffic. The number of emulated MNs also affects data traffic capacity. As the number of MNs increases, the maximum data capacity decreases. See Capacity and Throughput for CDMA2000 and GPRS data performance metrics.
You can effectively double the data capacity of your test case by executing the Network Host on a separate test server with the Network Host and IPv6 CN Node test cases. Select a remote network host in the Data Traffic pane and add the data test case to the same test session as your nodal test case. You can use the Automation Control feature to start the Network Host test case before your nodal test case executes, so that the host is listening for the data traffic when it begins.
| Basic Data Capability | A variety of Basic Data protocols are provided with the applicable test applications, including PING, RAW, UDP, TCP, and SCTP. The basic data capability allows you to select the protocol used in the test, define the payload size of the data packet, and define the rate used to send the data packets. |
| Advanced Data Capability | The Advanced Data feature enhances the basic capability by expanding the data protocols available with more complex, stateful data protocols. Advanced Data also gives you explicit control over the messages exchanged between the MN and the Network Host, allowing you to use a "real" application server as a remote Network Host rather than a Network Host node. You can design a sequence of messages that simulate data activities typically performed by a mobile user such as logging into a POP3 server and downloading email messages or accessing a web site. You can define the application layer (headers and content) of each request sent by the MN or the Network Host and an associated response from the other side. Message flow controls give you the ability to control the execution sequence of a message flow, including event handling, data connection triggering, and sequence re-direction. The powerful Auto-Fill Fields allow you to construct messages with dynamic content that can be based on test conditions or on information received in a message. Wizards are provided that can assist you in constructing a message sequence for a particular protocol and that can import a message trace into your DMF. With the optional IMS Security Testing feature, you can design data streams that can participate in IMS authentication from the standpoint of the MN or a CSCF. |
| Lite DMF | The Lite Data Message Flow window is used to define/edit Lite DMFs and Studio Scenarios converted into Lite DMFs. The Lite DMF format provides a simplified way to create and display a vast majority of data flows used for L4-L7 DPI testing (on Landslide). |
Test Operations
Data Traffic is enabled with the Data Traffic option of a nodal test case. Several types of data tests are available, and each is explained below. The measurements collected in Data Traffic testing include round trip latency between the MN and the Network Host node, overall data throughput of the SUT, and packet, byte, and error counters for both ends of the data stream.
The Dynamic IPSec feature adds the ability to encrypt bearer plane traffic and to simulate a VPN configuration with an MN connecting to a private network. The Network Host test case also supports IPSec, allowing it to act as both a remote host and an IPSec gateway if a physical IPSec gateway is not available. Data IPSec can be added to the test even when Data Traffic is disabled and the test simply attempts to establish SAs.
Verification Test
The simplest type of Data Traffic test is a Verification test. Its purpose is to verify connectivity between an MN and a Network Host by sending a single ping request and waiting for a reply. If the reply is received, the test succeeds; if not, the test fails. You can use a Verification test to confirm that the SUTs can simultaneously establish MN sessions and usable data connections for all MNs, or to troubleshoot your test definition and network routing.
Continuous Test
In a Continuous test, you can more closely simulate normal MN activity. Hundreds of thousands of MNs per test server can generate uplink traffic towards up to 5 Network Hosts, and the Network Hosts respond with downlink response traffic towards the MNs. Traffic can be continuously generated by active MNs or generated for a finite amount of time. You control the throughput, the protocols used, and when the traffic starts and stops. The data model in a Continuous test can be as simple as one-for-one or one-for-many packet exchanges to consume bandwidth or, with the Advanced Data protocols, client-server transactions, streaming media, or other content delivery that can test not only the capabilities of MN servicing nodes but also those of any packet inspection devices that may be in the data path. In this type of test, the MN acts as the client in a client-server model and normally initiates the transactions or exchanges. The uplink load is normally significantly less than the downlink load.
External Test
The External Data Sourcing feature provides inter-operability with other data generating devices. Landslide forwards traffic initiated by the generator towards the network and relays the response traffic back to the generator.
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