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DCOSS Frequently Asked Questions

  1. How do I connect the DCOSS to a switch/network/gateway?

  2. What accessories do I need with the DCOSS?

  3. What protocols are supported with the DCOSS?

  4. If I hear a harsh tone in the analog telephone what should I do?

  5. How do I route calls to a specific analog phone?

  6. How do I setup DCOSS for a simple loopback mode for testing?

  7. I have two (or more) trunk cards within my DCOSS and I wish to run more than one protocol during a session. How do I configure this?

  8. What is the maximum number of T1/E1 trunks that DCOSS can support? How about T3 support?

  9. Can the DCOSS and the T1/E1 Analysis boards (provided by GL) reside in the same computer?

  10. How many simultaneous Fax calls can be supported within a single DCOSS?

  11. How do I automate DCOSS? Do I need to learn a scripting language?

  12. What type of Voice Quality Testing is supported with the DCOSS?

  13. Can DCOSS be executed remotely?

  14. What PC platforms are available for DCOSS?

How do I connect the DCOSS to a switch/network/gateway?

The DCOSS utilizes an RJ-48 connection for each digital trunk (T1 or E1). Connecting to the system under test (SUT) requires either a crossover cable (the TX is connected to the RX and the RX is connected to the TX) or a straight cable. The crossover cable is more commonly used. Refer to the SS7 FAQ for additional information concerning SS7 connections. Connecting to the analog phone card requires that the supplied split cable be connected to the analog card using the 62-pin connector. This cable splits into two cables. The first split cable should be connected to the supplied DCOSS Power Supply using the five-pin amp connector. The second split cable should attach to a breakout box or supplied harmonica. Standard analog phones may be attached to the harmonica/breakout box using RJ-11 connectors.


What accessories do I need with the DCOSS?

The DCOSS is pretty much self-contained and, as a result, does not require many accessories. The power supply for the analog phones is required if analog phones are to be used. Turnover (crossover) cables may be purchased for the required connection between the DCOSS and the system under test (SUT). Analog phones may be purchased (or the user may use any standard analog phone).


What protocols are supported with the DCOSS

The DCOSS supports the following protocols.

Under the CAS signaling, the DCOSS supports:
R1 (robbed bit), T1 Loopstart, T1 Ground Start, T1 Feature Group D, E1 MFC-R2, E1 Digital European CAS, E1 Digital E&M, E1 SS5.

Under the PRI signaling, the DCOSS supports:
T1 ISDN (AT&T 5ESS, AT&T 4ESS, National ISDN 2, Nortel DMS 100/250)
T1 QSIG ISDN
E1 ISDN (France Telecom VNT, EuroISDN, Belgium, China, Great Britain, Sweden, Germany, Singapore)
E1 QSIG ISDN (ETSI)
T1/E1 Asian ISDN (Australian Telecom 1, Hong Kong Telephone, Nippon Telegraph Telephone, Korean Telecom)

Under SS7 signaling, the DCOSS supports:
MTP layers 1-3, ISUP, TUP, TCAP, SCCP

DCOSS also supports NOCC (no call control) which allows for no protocol.


If I hear a harsh tone in the analog telephone what should I do?

Hearing a harsh tone (non-crisp) within the analog telephone is a sign that the analog board is not configured for the correct encoding. When this occurs, the DCOSS will also not be able to detect digits from the analog phone. Exit DCOSS. From the windows main screen, click on the cfg icon (agcx_cfg.exe). The analog board configuration will be displayed for all analog boards. Select the board you wish to modify and click on Edit Board. Modify the Encode Law to either MU-Law (T1) or A-Law (E1). Do not modify any other values on this screen. Click on OK to exit this screen. Click on OK to exit the configuration screen. Execute dcos_set from the main window. Execute DCOSS.


How do I route calls to a specific analog phone?

From the main screen of DCOSS, click on File - DCOSS System Setup. This screen will display all analog phones available within your DCOSS. Modify the Phone Number of a specific phone port (physical connection from the breakout box/harmonica) for routing purposes. Two options for the phone routing are available. Phone Routing using the four-digit extension. The incoming call will be routed to a specific analog phone if the last four digits of the incoming number match a specific phone port. The Phone port must also be checked on for routing to occur. Phone Routing using full phone number (25-digit maximum). The incoming call will be routed to a specific analog phone if the entire incoming number matches a specific phone port. The Phone port must also be checked on for routing to occur. If the phone is onhook, the phone will ring and the user may answer the incoming call by taking the phone offhook. If the phone is offhook, the calling party will receive a busy detected from the DCOSS. The call will be terminated automatically.


How do I setup DCOSS for a simple loopback mode for testing?

Configuring DCOSS for loopback mode differs slightly depending on the protocol being used. First, connect a crossover RJ-45 cable (the TX is connected to the RX and the RX is connected to the TX) to the DCOSS; one end of the cable to trunk 0, the other end of the cable to trunk 1 (this may differ depending on which DCOSS trunks you wish to loopback).

CAS Protocols. The two trunks being placed in a loopback configuration must be configured with the same protocol and protocol configuration (using the DCOSS Protocol Configuration screen). After opening the trunks, use the DCOSS Manual Call Generation (1) screen to place a call on a desired timeslot. Use the DCOSS Manual Call Generation (2) screen to answer the call on the incoming timeslot (the opposite trunk).

PRI ISDN Protocols. The two trunks being placed in a loopback configuration must be configured with the same protocol and protocol configuration (using the DCOSS Protocol Configuration screen). One side of the loopback must be configured for Network; the other side of the loopback must be configured for Terminal (using the DCOSS Protocol Configuration screen). After opening the trunks, use the DCOSS Manual Call Generation (1) screen to place a call on a desired timeslot. Use the DCOSS Manual Call Generation (2) screen to answer the call on the incoming timeslot (the opposite trunk).

SS7 Protocols (Note that SS7 loopback requires two SS7 boards to be installed in the DCOSS). From within the SS7 configuration screen, configure SS7 board 0 with an OPC, DPC, Link, and Circuit Group. The Link should be placed on one side of the loopback. The circuit group should extend over an entire trunk or a partial trunk.

From within the SS7 configuration screen, configure SS7 board 1 with an OPC (use SS7 board 0 DPC value), DPC (use SS7 board 0 OPC value), Link, and Circuit Group. The Link should be placed on the opposite side of the loopback. The circuit group should extend over an entire trunk or a partial trunk. The Circuit Group must be identical for both sides of the loopback.

Make certain that the Switch Type, National/International parameter, Baud Rate, and Link Selection Code are identical for both SS7 boards. After saving and exiting the SS7 configuration screen, select the newly created configuration on the Protocol Configuration screen. Configure the Circuit Mapping so that the two circuit groups are on opposite trunks, utilizing the loopback configuration. After opening the trunks, use the DCOSS Manual Call Generation (1) screen to place a call on a desired timeslot (use a timeslot that was configured as a circuit group). Use the DCOSS Manual Call Generation (2) screen to answer the call on the incoming timeslot (the opposite trunk).


I have two (or more) trunk cards within my DCOSS and I wish to run more than one protocol during a session. How do I configure this?

During the execution of dcos_set.exe, select the desired protocol (signaling) for each of the associated trunk boards. Execute DCOSS. Configure each trunk (within each trunk board) as you would normally. This feature allows for multiple protocols to be run simultaneously on a single DCOSS to satisfy test criteria (i.e. SS7 and PRI ISDN). This also allows protocol conversion (SS7 inbound, PRI ISDN outbound) using the DCOSS Switch Routing.


What is the maximum number of T1/E1 trunks that DCOSS can support? How about T3 support?

A single DCOSS can support a maximum of 8 T1 or E1 or combination trunks. Current development plans will allow a maximum of 16 T1 or E1 or combination trunks by first quarter 2001.

GL outlines many options for T3 support.

T3 Option 1.

Seven fully loaded (8 T1 trunks per DCOSS) DCOSS systems will yield 56 T1 trunks, which results in two T3s. This configuration can be designed as seven rack mount DCOSSs utilizing monitor/keyboard/mouse switching. With the introduction of the 16 trunk DCOSS, you will require three sixteen-trunk DCOSS systems and one eight-trunk DCOSS to accomplish the dual T3 configuration. The resultant of the T1s from the DCOSS will be sent to two multiplexers to yield a dual T3 hookup.

T3 Option 2.

A single DCOSS with eight T1 trunks and a series of GL multiport repeaters will yield two T3s. This option will rely on a single T1 transmission being broadcast to seven T1s. The resultant of the multiport repeaters will be sent to two multiplexers to yield a dual T3 hookup.

T3 Option 3.

A single DCOSS with two GL T3 cards will yield two T3s. This option will rely on a single T1 transmission being broadcast to all 28 T1s within the T3 using the GL T3 board. The T3 board(s) can reside within the DCOSS computer for a total solution.


Can the DCOSS and the T1/E1 Analysis boards (provided by GL) reside in the same computer?

Yes. The DCOSS and the GL T1/E1 Analysis boards (single or dual) can reside in the same portable or rack mount computer. As a result, both the DCOSS and the T1/E1 Analysis may be operated simultaneously. This will allow for protocol analysis (SS7, ISDN, MFC-R2, ..) within the same box that is emulating the calls. This will allow for Call Capture and Analysis during DCOSS operations. This will allow for echo cancellation testing to take place on a single system with both DCOSS and T1/E1 Analysis.


How many simultaneous Fax calls can be supported within a single DCOSS?

With the optional hardware required for use with the Quad T1 and Quad E1 boards, DCOSS can support full faxing (240 channels simultaneously - send and/or receive). Faxes are sent using TIF files and faxes are received to DCOSS into TIF files. DCOSS fax supports V.27, V.29, V.33, and V.17 (up to 14400 bps).


How do I automate DCOSS? Do I need to learn a scripting language?

DCOSS automates calls using the Bulk Calling function. From within Bulk Calling, the user may configure, per timeslot, Bulk Call transmit and Bulk Call receive. The user has access to parameters such as Dialed Number, ANI Numbers, Duration of Call, Inter-Call Duration, Rings to Answer, Auto Busy Call. In addition, the user may configure each timeslot to send Voice Files, Faxes, Single/Dual Frequency Tones, or DTMF/MF Digits. Configuring DCOSS is simple and very user-friendly.

Each timeslot is configured individually so that flexibility is truly achieved. While Bulk Calling is running, the user has the option of modifying the Bulk Call configuration on the fly (changes take place on the next call for the particular timeslot in question). While Bulk Calling is running, the user may place manual calls on any unused timeslot using either the software or the analog phones. This will not interrupt Bulk Calling. While Bulk Calling is running, the user can add additional timeslots/trunks to the Bulk Call process.

Adding additional flexibility to the DCOSS Bulk Calling functionality, DCOSS offers Bulk Call Scripting. Bulk Call Scripting allows the user to create a Bulk Call Script; from within a very user-friendly, point and click interface, and add the Bulk Call Script to any timeslot within the Bulk Call configuration. The Bulk Call Script allows for conditional statements, loops, and full access to all functions within DCOSS. Each Bulk Call Script created may be used for many timeslots, or the user may use many scripts within a single Bulk Call configuration. Bulk Call Scripts and Bulk Call configurations, as described above, may be combined into a single configuration. The possibilities are limitless.

After the Bulk Call configuration is created (including Bulk Call Scripts), the Bulk Call configuration may be saved to the DCOSS database. The user may save as many Bulk Call configurations as the DCOSS hard drive will support. The user may also export and import Bulk Call configurations from one DCOSS to another DCOSS.


What type of Voice Quality Testing is supported with the DCOSS?

DCOSS supports PAMS (Perceptual Analysis Measurement System, ITU-T P.800), PSQM (Perceptual Speech Quality Measure, ITU-T P.861), and PSQM+. Using the DCOSS Voice Quality Testing (VQT), arecorded voice file (PCM or WAV) may be tested against a reference voice file (PCM or WAV) using PAMS, PSQM, and PSQM+. The VQT may be executing on a single timeslot at a time, but, using flexible parameters within the DCOSS Bulk Call Generator, the VQT may be executing from within Bulk Calling. VQT may also be executed manually by entering a reference voice file and a degraded voice file.

The resultant of the VQT produces Listening Effort/Listening Quality as part of the PAMS algorithm and an MOS as part of the PSQM/PSQM+ algorithms.


Can DCOSS be executed remotely?

Yes. DCOSS recently introduced a client/server option. This option will allow a client (located on WIN 95, 98, 2000, NT, Unix, ) to control a single DCOSS or many DCOSS over a LAN, WAN, or Internet. The Client will incorporate a DLL or an OCX that can be used for development of a user GUI. This allows for script writing, adding DCOSS Client to an existing Test program, or adding to DCOSS functionality user defined methodology for executing DCOSS. From the DCOSS Client, the user may also utilize a command-line prompt (supplied) to execute the many functions of DCOSS.

What PC platforms are available for DCOSS?

The following PC Platforms are available for DCOSS:


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