Tech-X Flex™ Base Unit User Guide
Spirent Communications 20324 Seneca Meadows Parkway Germantown, MD 20876 USA +1 301.444.2400 800.385.0110 (USA only) www.spirent.
Tech-X Flex™ Base Unit User Guide Issue 1 Contents 1: Introduction 1.1 Documentation notes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-1 1.1.1 Document purpose and scope . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-1 1.1.2 Definitions of terms and acronyms . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-1 1.1.3 Additional documentation . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Base Unit User Guide Issue 1 Tech-X Flex™ 1.5 Technical support . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-17 2: Wi-Fi Testing Menu Intro 2.1 Functionality note . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-2 2.2 Wi-Fi overview . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-2 Wi-Fi 2.2.1 Wi-Fi support details . . . . . . . . . . . . . . . . . . . . . . .
Tech-X Flex™ Base Unit User Guide Issue 1 3.9 Passive testing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-4 Intro 3.9.1 Unit setup for passive testing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-4 3.9.2 Passive Video Quality of Service (QoS) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-5 4: System Menu 4.1 Record Manager . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Base Unit User Guide Issue 1 Tech-X Flex™ 5.5 Web Browser . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5-6 5.5.1 Setup - Web Browser . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .5-7 Intro 5.6 IP Video testing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5-7 Wi-Fi 5.6.1 Video Quality of Service (QoS) . . . . . . . . . . . . . . . . . . . . . . . .
Tech-X Flex™ Base Unit User Guide Issue 1 1: Introduction This section provides an overview of the Tech-X Flex product and includes the following information: • Documentation notes on page 1-1 - Describes this document and the terminology within. • Product introduction on page 1-2 - Describes the physical unit and includes a high-level overview of system features and capabilities. • General product handling and operation on page 1-9 - Describes basic procedures for handling and operating the unit.
Base Unit User Guide Issue 1 Tech-X Flex™ Unit - A Tech-X Flex device in general, with or without a module attached, as applicable to the respective context. • Base Unit - The core handheld component to which modules attach. The base unit has an independent suite of functionality which is described in this document. The use of modules does not change base unit functionality.
Tech-X Flex™ Base Unit User Guide Issue 1 Wi-Fi Primarily, the unit is able to emulate various devices within a home network and perform testing to sectionalize problems. For example, if a subscriber cannot access the internet, the unit can emulate a home computer and verify whether ISP connectivity is actually available. The unit can also perform a variety of other connectivity-related and statistics-gathering functions.
Base Unit User Guide Issue 1 Tech-X Flex™ Intro Wi-Fi 10/100 • Ethernet and IP connectivity testing - With its 10/100 interface, the unit can link to an Ethernet network at any standard transport device such as a home router, hub, or Ethernet switch. Once linked, the unit can join an IP network and perform testing such as ping, traceroute, and internet webpage access.
Tech-X Flex™ Base Unit User Guide Issue 1 LED indicators Intro Power on/off Wi-Fi antenna Strap mount Tech-X Flex CHARGE Wi-Fi ERRORS [System] Back 0: Record Manager 1: 10/100 Admin Port 2: Set Date and Time 3: Auto Sleep Mode 4: Version Info 5: Battery Status 6: Channel Guide/Network Setup 7: Download Channel Guide 8: Wireless ON/OFF MoCA 10/100 F2 F3 F1 Exit System F4 Arrow keys ENTER Backlight EXIT 1 4 Help GHI 7 2 ABC 5 JKL 8 3 DEF 6 MNO 9 PQRS TUV WXYZ N1 0 HELP
Base Unit User Guide Issue 1 Table 1-1 Tech-X Flex™ Front panel feature descriptions Intro Wi-Fi 10/100 System IP/Video Indicator Function Power on/off Powers the unit on and off, and is also used to place the unit into sleep mode (see Powering on/off and sleep mode on page 1-9). LED indicators See LED indicators on page 1-6. Strap mount See Attaching the strap on page 1-11. Wi-Fi antenna See Attaching the Wi-Fi antenna on page 1-10.
Tech-X Flex™ Indicates the status of the link over the active interface. For example, when using the WiFi interface, the LED indicates the status of the Wi-Fi link. The general behavior is as follows: • Solid green - The unit is properly linked and/or synchronized with a comparable farend device. For the 10/100 interface, the LED is solid green any time the interface is configured with IP information, but does not necessarily indicate that the information is valid and routable.
Base Unit User Guide Issue 1 Tech-X Flex™ 1.2.
Modules have their own physical interfaces. See the documentation for the respective module for more information. • The two Ethernet interfaces are used for 10/100 testing and for administrative functions on the unit, such as upgrading firmware. • The 2.5 mm mic/headset jack and USB port are for future use. 1.3 General product handling and operation 10/100 This section provides basic information for general operation.
Base Unit User Guide Issue 1 Tech-X Flex™ connection. Likewise, to attach a module, gently press the module into the base unit to seat the electrical connection, then finger-tighten the screws. Intro Fastener screws Wi-Fi 10/100 Module System Figure 1-4 Rear of unit with a module installed, showing the fastener screws IP/Video Once a module is attached and has booted up, a menu corresponding to the module functionality will appear over the F1 function key.
Base Unit User Guide Issue 1 Intro Tech-X Flex™ Wi-Fi CHARGE 10/100 Figure 1-5 Attaching the antenna Figure 1-6 Antenna positioned for typical use, following attachment 1.3.4 Attaching the strap A strap with a hook is provided to hang the unit while working.
Base Unit User Guide Issue 1 Tech-X Flex™ (To hook) Intro Strap end Wi-Fi Tech-X Flex 10/100 SYNC DATA ERRORS CHARGE Figure 1-7 Sliding the open strap end through the strap mount Next, feed the open end through the bottom of the buckle as shown in the following figure: System Buckle (To hook) IP/Video Strap end Specs 2 Figure 1-8 Feeding the strap through the buckle 1-12 1: Introduction
Tech-X Flex™ Base Unit User Guide Issue 1 The unit display includes touchscreen functionality which allows you to operate most display controls by touching the screen. You should use a plastic stylus or a similar device. It is recommended to avoid using your fingers because it is difficult to control selections with precision. Intro 1.3.5 About the touchscreen display CAUTION: Never use a sharp or metallic object which will damage the screen. Likewise, 1.3.
Base Unit User Guide Issue 1 Tech-X Flex™ 1. Using the function keys or the touchscreen, select the correct menu/interface. Intro A function key selects the function/test/menu directly above 8: Wireless ON/OFF Wi-Fi MoCA F1 Wi-Fi F2 10/100 F3 System F4 10/100 2. Using the up/down arrows, number pad, and/or touchscreen, select the desired menu item and possibly submenu items to activate the desired function/test. System 3.
Tech-X Flex™ Base Unit User Guide Issue 1 The text entry pad is similar to a standard text message device, where you must press a key multiple times to cycle through the associated letters. For example, to enter a “b”, press the “2” key three times quickly, then pause. • The N1 key allows you to enter special characters, such as a period. • The Help button on the physical keypad acts as a backspace.
Base Unit User Guide Issue 1 Tech-X Flex™ 1.4.1 Battery replacement Users may perform field replacement of the battery pack. Note the following: Intro • New battery packs should be ordered from Spirent. • Batteries contain hazardous contaminants and should be disposed of according to local regulations. It may be illegal to discard batteries in the general trash. To replace the battery pack Wi-Fi 1. On the back of the unit, remove the two battery pack anchor screws, under the base of the kickstand.
Base Unit User Guide Issue 1 3. Using the two screws at the base of the battery pack unit, remove the old battery from the plastic holder and replace with the new battery, 4. Carefully reinstall the battery pack and screws. NOTE: Do not overtighten the screws, which could cause the battery pack cover to crack. 1.5 Technical support If you need product assistance or want to report problems with the product or the documentation, please contact us. Phone: or +1 301.444.2400 +1 800.321.
Base Unit User Guide Issue 1 Tech-X Flex™ E-mail: systemssupport@spirent.
Tech-X Flex™ Base Unit User Guide Issue 1 2: Wi-Fi Testing Menu Wi-Fi testing on the unit includes: • Scanning for available wireless access points • Connecting to an existing network and obtaining IP information • Basic network-level testing such as ping, traceroute, and web browsing All Wi-Fi testing is performed from the Wi-Fi menu. When this menu is active, all testing uses the Wi-FI interface only. That is, no other interface will process test requests.
Base Unit User Guide Issue 1 Tech-X Flex™ 2.1 Functionality note Wi-Fi connection and testing is a purchasable option. Please contact Spirent for more information. Intro 2.2 Wi-Fi overview The following sections describe general information about the unit and Wi-Fi. Wi-Fi 2.2.1 Wi-Fi support details 10/100 The unit supports connection to IEEE 802.11b (“Wireless-B”) networks using the 2.4GHz range.
Base Unit User Guide Issue 1 Intro Tech-X Flex™ Home computer Wi-Fi Wireless router Ping 10/100 Provider network/ISP Ping, traceroute, web browsing System Figure 2-2 Typical Wi-Fi testing diagram 2.2.
Base Unit User Guide Issue 1 Tech-X Flex™ Intro Wi-Fi • The Wi-Fi antenna is properly connected to the unit (see Attaching the Wi-Fi antenna on page 1-10.) • If entering all information manually, you have properly identified the network. Because this is an errorprone process, it is recommended that you use the auto-scan feature to find the network and prepopulate many of the parameters (see Wi-Fi Setup > Scan on page 2-5.) • The network is not an “adhoc” network, which the unit does not support.
• When you initiate a connection with Wi-Fi Setup > Connect or with the Connect shortcut from the Wi-Fi Setup > Scan results, you can specify whether to add the network to the auto-connect list following the connection attempt. The network is added whether or not the connection is successful. (see Setup - Connect (Wi-Fi Setup) on page 2-7).
Base Unit User Guide Issue 1 Tech-X Flex™ Setup - Scan (Wi-Fi Setup) Intro The Wi-Fi Scan requires no setup parameters. The process launches immediately following the menu selection Results - Scan (Wi-Fi Setup) Wi-Fi The scan lists all networks within range of the unit, including the SSID (name), signal strength, and channel number for each network. For more information on these fields, see the descriptions under Wi-Fi Setup > Details on page 2-9.
Tech-X Flex™ Base Unit User Guide Issue 1 NOTE: If you have trouble connecting, see If you cannot connect (troubleshooting tips) on page 2-3. Intro Once the unit successfully connects, the network parameters are saved in memory under the respective SSID (name). Setup - Connect (Wi-Fi Setup) Description SSID (Service Set Identifier) Network name. Channel Number Channel used by the network, typically 1 to 11 with variances possible based on the country of operation and applicable regulations.
Base Unit User Guide Issue 1 Table 2-2 Tech-X Flex™ Connect (Wi-Fi Setup) - Setup parameters page 2 Intro Parameter Description Key Type and Key Type of key and the key itself, as follows: Wi-Fi • If Key Type = HEX, the Key must be a hexadecimal number. A hex digit occupies four bits, so for WEP-64, a hex Key must be 10 digits (40 bits total). For WEP-128, a hex Key must be 26 digits (104 bits total).
Base Unit User Guide Issue 1 Wi-Fi Intro Tech-X Flex™ Results - Connect (Wi-Fi Setup) The unit reports whether the connection was successful or not. If the connection is successful, the SYNC LED lights as solid green. If the connection failed and you don’t know why, see If you cannot connect (troubleshooting tips) on page 2-3. NOTE: After connection, you must obtain an IP address if you want to do any IP-based testing. For more information, see IP Network Setup on page 5-1. IP/Video 2.3.
Base Unit User Guide Issue 1 Table 2-4 Tech-X Flex™ Details (Wi-Fi Setup) - Results Intro Result Description Security Type of security in use by the network: • NONE - No security (open access) • WEP - Wired Equivalent Privacy Wi-Fi 10/100 Signal Strength Signal power level. Channel Number Channel used by the network, typically 1 to 11 with variances possible based on the country of operation and applicable regulations.
Tech-X Flex™ Base Unit User Guide Issue 1 2.6 Traceroute Intro Traceroute testing over the Wi-Fi interface is similar to other interfaces. For more information, see Traceroute on page 5-5. NOTE: The web browser is a purchasable option. Please contact Spirent for more information. Specs IP/Video System 10/100 Use of the web browser over the Wi-Fi interface is similar to other interfaces. For more information, see Web Browser on page 5-6. Wi-Fi 2.
Base Unit User Guide Issue 1 Tech-X Flex™ Intro Wi-Fi 10/100 System IP/Video Specs 2-12 2: Wi-Fi Testing Menu
Tech-X Flex™ Base Unit User Guide Issue 1 3: 10/100 Testing Menu With the 10/100 testing menu, the unit is able to join a 10/100 Ethernet link and perform the following functions and tests: • IP address retrieval/assignment (See IP Network Setup on page 5-1) • IP ping (See Ping on page 5-4) • Traceroute (See Traceroute on page 5-5) • Internet web page request (See Web Browser on page 5-6) • IP video testing (See IP Video testing on page 5-7) • Ethernet bridging and passive testing (See Passive
Base Unit User Guide Issue 1 Tech-X Flex™ 3.1 Functionality note Intro Your unit may or may not include all the functionality described in this section, dependent upon your licensing agreement with Spirent. Please contact Spirent for more information. 3.2 About the 10/100 ports and connections Wi-Fi The unit has two physical 10/100 ports which are connected internally by a functional Ethernet switch. Therefore, when performing single-ended tests such as ping or traceroute, you may use either port.
Tech-X Flex™ Base Unit User Guide Issue 1 IP Network Setup allows you to assign IP routing information to the unit in order to perform IP-based testing. This function operates similarly to other interfaces; however, note that when launched from the 10/100 menu, the assigned IP information applies to the 10/100 interface/connection only. Intro 3.4 IP Network Setup NOTE: The unit must be connected to a suitable access device before attempting IP Network setup (see 10/100 testing diagram on page 3-2).
Base Unit User Guide Issue 1 Tech-X Flex™ 3.9 Passive testing NOTE: Passive testing is a purchasable option. Please contact Spirent for more information. Intro Passive testing allows non-intrusive testing on a bridged Ethernet link. The following sections describe passive testing and bridge setup in more detail. Wi-Fi 3.9.
Tech-X Flex™ Base Unit User Guide Issue 1 1. Connect the physical wires between the endpoints, from router-to-unit and unit-to-STB. 3. Set up and run the desired test on the unit. The following notes apply: • Following successful IP Network Setup, you can also perform single-ended active tests while the link is bridged, in either direction. In the previous example, you should be able to ping the STB if you know its IP address, as well as anywhere upstream, including the internet.
Base Unit User Guide Issue 1 Tech-X Flex™ Intro Wi-Fi 10/100 System IP/Video Specs 3-6 3: 10/100 Testing Menu
Tech-X Flex™ Base Unit User Guide Issue 1 4: System Menu The System menu provides access to general system configuration. Figure 4-1 System main menu 4.1 Record Manager Select System > Record Manager. The Record Manager is used to create, delete, and view record files, which are special files used to store test results. When you invoke the “Save” function in a results screen, they are saved to a record file.
Base Unit User Guide Issue 1 Tech-X Flex™ NOTE: All records and associated results remain on the unit until manually deleted. A unit shutdown will not delete record data. Intro The unit has no specific maximum to the number of record files or the amount of results that any record can contain. However, it does have a certain overall limit related to the constraints of physical memory.
Tech-X Flex™ Base Unit User Guide Issue 1 Intro Currently, this function is used as a prerequisite for management activities such as firmware upgrades and channel guide imports. It does not provide general access to the operating system of the unit. For more information on firmware upgrades, see Update Firmware on page 4-10. 4.3 Set Date and Time The date and time are used to timestamp all saved results in the Record manager.
Base Unit User Guide Issue 1 Tech-X Flex™ 4.4 Auto Sleep Mode Select System > Auto Sleep Mode. Intro This function sets the maximum amount of idle time after which the unit automatically enters “sleep mode” in order to save battery power. It does not apply when the unit is powered by an external source. For more information on sleep mode, see Powering on/off and sleep mode on page 1-9. Wi-Fi 4.5 Version Info Select System > Version Info.
Tech-X Flex™ Base Unit User Guide Issue 1 4.7 Channel Guide/Network Setup Parameters Description Use Guide Indicates whether a channel guide is currently active for video test setup. For more information, see About channel guides on page 4-7. Guide Name Name of the active channel guide, only applicable when Use Guide is set to Yes. The field allows you to select from the guides currently on the unit, if any. If the field is blank, no channel guides have been imported.
Base Unit User Guide Issue 1 Table 4-3 Tech-X Flex™ Channel Guide/Network Setup - Page 2 parameters Intro Parameters Description Int’l Code Country/continent code. This specification allows the analysis to adjust the quality metric scores according to statistical data available in different parts of the world.
Tech-X Flex™ Base Unit User Guide Issue 1 Within the channel guide file itself (not on a video test screen), a sample entry might appear as follows: ...where the element names intuitively denote each respective parameter, such as and . To be functional, a channel guide must be well-formed and conform to the proper schema. For more information on schemas and channel guide generation, please contact Spirent.
Base Unit User Guide Issue 1 Tech-X Flex™ 1. Place the channel guides on a networked computer that has an approved FTP server running. This section describes how to install and set up that server. 2. Run the import function on the unit.
The IP address or DNS name of the host computer where the FTP server application is running. Port The port on which the FTP server is listening for requests. The default is 21 but can be changed in the FTP server setup. User ID The name of the user account that you set up in the previous procedure. Password The password of the user account, if one was specified. 4. On the unit, click Start to initiate the import.
Base Unit User Guide Issue 1 Tech-X Flex™ 4.10 Calibrate Touchscreen Select System > Calibrate Touchscreen. Intro This function calibrates the touchscreen display for optimal response. Calibration should be done after firmware upgrades, after battery replacement, or if the screen response begins to degrade after heavy use. Wi-Fi The process requires you to touch the screen in several places with a stylus or other approved device. Follow the instructions on the screen. 4.
Base Unit User Guide Issue 1 • The host that contains the firmware must be set up in a specific manner. Please contact Spirent for a separate document that provides details on this setup and other information about firmware upgrades. • The 10/100 admin port must be set up before this menu command becomes available (see 10/100 Admin Port on page 4-2). Intro Tech-X Flex™ Specs IP/Video System 10/100 Wi-Fi Please contact Spirent for additional information about upgrading firmware.
Base Unit User Guide Issue 1 Tech-X Flex™ Intro Wi-Fi 10/100 System IP/Video Specs 4-12 4: System Menu
Tech-X Flex™ Base Unit User Guide Issue 1 5: IP and Video Testing This section describes the suite of IP and video (IPTV) functions available on the unit. These tests are available over various interfaces on the unit, including the Wi-Fi and Ethernet interfaces, and modular interfaces such as MoCA. Not all tests are available for all interfaces; see the respective documentation for specific testing support.
Base Unit User Guide Issue 1 Tech-X Flex™ information required to send and receive IP traffic. For any interface, IP Network Setup is a required prerequisite to any test that sends and/or receives IP data over that interface. Intro IP Network Setup must be performed each time the unit is started up, for the interface(s) that you intend to use. Furthermore, you may need to run the setup again after switching test menus, if the menu change activates a different interface on the unit.
Base Unit User Guide Issue 1 • Ensure that you have specified generally valid IP information. For example, the unit cannot assign an address of 0.0.0.0 because it is not valid for IP communications. • For static assignment, the DNS server address is optional. However, if you do not specify a valid server, you must know the target IP address for any IP-based tests. That is, the unit will be unable to resolve domain names such as www.google.com.
Base Unit User Guide Issue 1 Tech-X Flex™ 5.3 Ping Intro IP Ping is a basic connectivity test that verifies whether a specific IP address can be reached. It sends a set of ICMP echo requests to an IP address and reports whether replies are successfully received. The request is sent via the active interface of the unit and requires that routable IP information is assigned to that interface. For more information, see IP Network Setup on page 5-1. 5.3.
Base Unit User Guide Issue 1 Wi-Fi Intro Tech-X Flex™ 5.4 Traceroute This test is the standard ICMP traceroute function that sends three traceroute requests to a destination address and reports every router “hop” along the path, up to 30 hops. The results provides a topological view of the route that the packets used to reach the destination. 5.4.
Base Unit User Guide Issue 1 Tech-X Flex™ 5.4.2 Results - Traceroute test Intro The unit reports the IP address of each sequential hop along the path to the target, along with the roundtrip time required for each hop to receive the request and the unit to receive acknowledgement. Because three independent requests are sent, each hop shows three different roundtrip times.
Tech-X Flex™ Base Unit User Guide Issue 1 5.5.1 Setup - Web Browser Web Browser - Setup parameters Intro Table 5-5 Parameters Description URL Target address of the web page to load, either a dotted IP address or a URL if a DNS is available. For example: Wi-Fi 208.22.58.142 www.google.com Note the following: 10/100 • When entering a URL, case is unimportant because all characters are converted to lower case when the browser is launched. • The unit remembers the recent addresses you entered.
Base Unit User Guide Issue 1 Intro • Channel Guide/Network Setup on page 4-5 (System menu) • Video Quality of Service (QoS) on page 5-8 • Channel Change Time on page 5-30 Tech-X Flex™ 5.6.1 Video Quality of Service (QoS) NOTE: Video testing is a purchasable option. Please contact Spirent for more information.
Base Unit User Guide Issue 1 Wi-Fi Intro Tech-X Flex™ Description Channel Num If a channel guide was used, the channel number and abbreviation that was selected in the previous screen. If no channel guide is active, these fields do not appear. For more information on channel guides, see About channel guides on page 4-7. Channel Abbr IP Address IP address of the video stream. If you selected a channel from the channel guide, this field is automatically populated.
Base Unit User Guide Issue 1 Table 5-6 Tech-X Flex™ Video QoS test - Setup parameters Intro Parameter Description IP Port UDP port of the video stream. Similar to the IP Address, this must be the destination port in the UDP packet header. If you selected a channel from the channel guide, this field is automatically populated. Wi-Fi Optionally, you can select As IP Add from the drop-down list which indicates to ignore the port and use the IP address exclusively for identifying video stream packets.
Tech-X Flex™ Options include: • F or FIXED - The jitter buffer uses a constant fixed delay. The jitter buffer is bounded by a nominal and maximum delay, where the nominal delay dictates the actual delay and the maximum delay dictates the maximum number of packets that can be stored in the jitter buffer.
Base Unit User Guide Issue 1 Table 5-6 Tech-X Flex™ Video QoS test - Setup parameters Intro Parameter Description GOP Length Number of frames in a group of pictures (GOP) on the stream, related to the GOP type. This is essentially the I-frame update interval; that is, the number of frames from one I-frame to the next. This value is used only as a default if the actual frame types and GOP structure cannot be dynamically detected from the stream.
Tech-X Flex™ Video QoS test - Setup parameters Parameter Description Original Quality Original picture quality. This value represents the subjective quality of the video before encoding, which is the theoretical maximum that the quality ever could be after encoding, transport, and decoding. Intro Table 5-6 Base Unit User Guide Issue 1 Video coder class, which describes the ability of the stream to tolerate packet loss with respect to perceived quality.
Base Unit User Guide Issue 1 Table 5-6 Tech-X Flex™ Video QoS test - Setup parameters Intro Parameter Description International Code Country/continent code. This specification allows the analysis to adjust the quality metric scores according to statistical data available in different parts of the world.
Base Unit User Guide Issue 1 All quantitative measurements apply to the reporting period only. No measurements are cumulative. • Unless indicated otherwise, any reference to “packets” means MPEG packets, not IP packets. Table 5-7 Intro • Video QoS results - Summary results, Plot tab Description MOS graph Displays graph of calculated V-MOS, A-MOS, and AV-MOS, which updates regularly for continuous tests. The graph assumes a fixed score of 4.0 as passing and 3.0 as marginal.
Base Unit User Guide Issue 1 Table 5-9 Tech-X Flex™ Video QoS - Summary results, Stream/Expert Analysis tab Intro Result Description Codec Type Stream type, as defined in ITU Spec ISO/IEC 13818-1. Image Size Horizontal resolution, indicating the left-right size of the image, in pixels. -and- Wi-Fi Vertical resolution, indicating the top-bottom size of the image, in pixels. Image Type Type of the image.
Tech-X Flex™ Base Unit User Guide Issue 1 Discards Total number of packets discarded by the jitter buffer emulator containing data for the respective frame type; for example, the total number of packets discarded containing I-frame data. These results are packet counts, not frame counts. Impairments Total number of frames errored, by type. A frame is considered errored if a single packet containing data for it is lost or discarded.
Base Unit User Guide Issue 1 Tech-X Flex™ Table 5-12 Video QoS - Stream results, Video Scores tab Intro Result Description VSTQ Video service transmission quality. This is a codec-independent measure related to the ability of the bearer channel to support reliable video. Valid values are: Wi-Fi 0 - 100 VSPQ Video Service Picture Quality. This is a codec-dependent measure of the subjective quality of the decoded video stream. It is equivalent to a V-MOS score, using a different scoring range.
Tech-X Flex™ Base Unit User Guide Issue 1 Result Description OOS Pkt Rate Number of video/audio stream packets that arrived out of sequence, as detected by the jitter buffer emulator. Burst Loss Rate Average percentage of media independent units (MIUs) lost and/or discarded during burst periods. Wi-Fi NOTE: For further information about bursts and gaps, see About gap and burst states on page 5-29. Average burst period length in milliseconds.
Base Unit User Guide Issue 1 Tech-X Flex™ Table 5-14 Video QoS - Transport results, MPEG Stats tab Result Description Intro Wi-Fi PCR Repetition Err Number of times that the interval between PCR (program clock reference) transmissions exceeded 100 ms, if the discontinuity indicator is not set. The PCR is used as a time synchronization tool between the encoder and decoder. If the discontinuity indicator is not set, the encoder expects a 100 ms or smaller interval between PCRs.
Temporal redundancy - Adjacent video frames often have many similarities, especially with video of still or slow-moving objects. In this case, sequential frames may have redundant information expressed over time as the video is played. In the end, the encoders/decoders effectively form a system where the technology is able to interpolate redundant data, without the need to transmit it.
Base Unit User Guide Issue 1 Tech-X Flex™ Intro received the referenced frame before the B-frame can be decoded, making the frame order different from the actual display order. Therefore, B-frames can cause a delay in the decoding process, because the decoder must buffer the input while reordering the frames for display. Of the three, the loss of a B-frame generally causes the least impact to picture quality.
Base Unit User Guide Issue 1 Audio compression has some similarity to video compression, in that techniques may be used to eliminate redundant data. Furthermore, audio exhibits the concept of “masking,” where one frequency may mask another and the human ear is unable to perceive it. Because it is unnecessary to transmit any data for sounds that will never be heard, the removal of this data from the original audio stream provides further possibilities for data reduction.
Base Unit User Guide Issue 1 Tech-X Flex™ Intro Wi-Fi 10/100 System • Elementary stream - The elementary stream is the basic compressed audio or video bitstream. In the case of a video stream, this is the original content segmented into macroblocks, slices, and frames, then packetized with header information required to reconstruct the stream at the far end.
Tech-X Flex™ Base Unit User Guide Issue 1 IP multicast is a set of protocols that allows a single IP packet to be sent to multiple hosts (that is, “group members”) without the need to send multiple redundant copies of the same packet from the source. It serves to alleviate network congestion when multiple hosts need to receive the same traffic, such as the case where multiple IPTV subscribers are watching the same channel and each will ultimately receive the exact same data payload.
Base Unit User Guide Issue 1 Tech-X Flex™ R1 Intro R2 Wi-Fi R5 R3 10/100 R4 System Figure 5-8 Hypothetical multicast network with multicasting and IGMP IP/Video In this example, the routers are multicast-aware and can make intelligent decisions about packet forwarding.
Protocol Independent Multicast (PIM) to build logical multicast trees and forward packets efficiently between the multicast source and group members. Once multicast packets reach their destination subnets, group members "listening" for packets with the specific IP multicast (destination) address will receive and process the packets accordingly. The IP address range of 224.0.0.0 - 239.255.255.255 is reserved for multicast packets.
Base Unit User Guide Issue 1 Tech-X Flex™ Intro Wi-Fi 10/100 • Other problems related to network impairments, such as packet delay variation and out-of-sequence packets. • The inherent abilities of the codec and associated equipment to conceal network impairments such as packet loss. • The structure and length of GOPs (MPEG Groups of Pictures), especially with regards to the varied effects of packet loss on different frame types.
Tech-X Flex™ Base Unit User Guide Issue 1 The software models the distribution of packet loss over the measurement duration, which allows for a more detailed characterization of the packet loss experienced by the audio/video stream. This is a fourstate model in which two periods of loss exist, gap and burst periods, each of which has two states. The stream is considered to be in a gap condition of loss when consecutive packet loss is less than or equal to one packet.
Base Unit User Guide Issue 1 Tech-X Flex™ Note that the usage of PDV versus PPDV is a complex subject and is beyond the scope of this document. Intro Additional video testing notes About the IP address specified for testing Wi-Fi The IP address specified must reflect the destination IP address for video stream packets; that is, the first address contained in the IP packet headers. For a multicast stream, this will be a multicast IP address, not an IP address of a host on the network under test.
Tech-X Flex™ Base Unit User Guide Issue 1 For more detailed information on the time calculation, see How channel change time is calculated on page 5-32. Intro a multicast stream and initiating an actual channel change, emulating the behavior of IPTV subscriber STB equipment. With an active channel guide: Figure 5-9 Change Channel Setup - Page 1 (with channel guide) NOTE: The screen has a small display area and can only show a limited number of channels from the guide at once.
Base Unit User Guide Issue 1 Tech-X Flex™ Intro • IP Address - IP address of the multicast stream • IP Port - UDP or TCP port of the stream, with respect to the Encapsulation Method • Encapsulation Method - Transport encapsulation used for the stream • Codec - Video codec type Results - Channel Change Time Wi-Fi The test reports the channel change time in msec, along with other parameters used in the calculation. For more information, see How channel change time is calculated on page 5-32.
Tech-X Flex™ Base Unit User Guide Issue 1 Channel Leave Time - Equals the (LastA - ML) term. • Channel Join Time - Equals the (FirstB - MJ) term.
Base Unit User Guide Issue 1 Tech-X Flex™ Intro Wi-Fi 10/100 System IP/Video Specs 5-34 5: IP and Video Testing
Tech-X Flex™ Base Unit User Guide Issue 1 6: Specifications This section provides detailed information on physical components and specifications of the Tech-X Flex base unit. NOTE: Specifications are subject to change. 6.1 General specifications Table 6-1 Physical specifications Dimensions (H x W x D) • 8.964 in x 4.208 in x 2.524 in • 22.77 cm x 10.69 cm x 6.41 cm Weight 2.0 lb. (0.91 kg) Display Color LCD with adjustable backlight.
Base Unit User Guide Issue 1 Table 6-2 Tech-X Flex™ Power specifications Intro AC operations External AC adaptor/charger NOTE: Adaptor will charge battery while unit is in use.
Tech-X Flex™ Base Unit User Guide Issue 1 Co-location - This transmitter must not be co-located or operated in conjunction with any other antenna or transmitter. • Compliance - This device complies with Part 15 of FCC rules. Operation is subject to the following two conditions: 1 This device may not cause harmful interference and, 2 This device must accept any interference received, including interference that may cause undesired operation.
Base Unit User Guide Issue 1 Tech-X Flex™ Intro Wi-Fi 10/100 System IP/Video Specs 6-4 6: Specifications
