GL Communications Inc.
Home >  Digital Central Office Switch Simulator (DCOSS)

DCOSS Available Protocols

The following are available protocols for the DCOSS system. Within each protocol, the DCOSS user interface allows all protocol parameters, protocol setup parameters as well as call setup parameters to be configured by the user. Thus, a user may completely change the configuration for a given protocol, induce protocol errors or protocol violations, as well as create a completely new configuration for a given protocol. This allows great flexibility within a specified protocol. It should be noted, however, that the protocol configurations delivered with the DCOSS system are certified for a specific network/country and may not be modified. However, the certified configurations may be copied.

User's Guide
Product Brochure
View Presentation
GL Product Lists
  • CAS T1/E1
        - R1 (WINK)
        - T1 Loopstart
        - T1 Ground Start
        - T1 Feature Group D
        - T1 Immediate Start
        - E1 MFC-R2
          Certified Countries Available: Argentina, Bahrain, Bolivia, Brazil, Chile, China, Columbia, Czech Republic, Honduras,       Indonesia, Korea, Malaysia, Mexico, Panama, Philippines, Singapore, Thailand, and CCITT
        - E1 Digital European CAS (Italy, Netherlands, Sweden)
        - E1 Digital E&M (Brazil and Indonesia)
        - E1 International Wink Start
        - User-Configurable State Machine

  • SS7 Signaling - MTP 1-3, ISUP, TUP, TCAP/SCCP, and SCP

  • PRI ISDN (Europe, USA, Asia)

    Europe France Telecom VN6 (ETSI)
    EuroISDN (Available countries: Austria, Denmark, Finland, Greece, Iceland, Ireland, Italy, Liechtenstein, Luxembourg, Netherlands, Norway, Portugal, and Spain) Belgium, China, Great Britain, Sweden, Germany, Singapore, European QSIG
    USA (includes ISDN-NFAS)
    Northern Telecom DMS 100
    AT & T 5ESS10
    AT&T 4ESS
    US National ISDN2 (BellCore)
    Asia Australian Telecom 1
    Hong Kong Telephone
    Nippon Telegraph Telephone
    Korean Telecom
  • Fax & Modem over T1E1
  • Fax & Modem over VoIP T.38
  • SS5
  • No Call Control

Additional Protocol Information

SS7 Protocol (Go to SS7 Page)

SS7 is a very flexible, yet complex signaling protocol. Establishing a working link(s) as well as placing simple and complex calls is not always easily accomplished. DCOSS SS7 provides the required flexibility to handle all your SS7 requirements.

Screenshot of SS7 Protocol Parameter Configuration

The DCOSS SS7 may be configured as either an SSP, STP (allows SSP as well as STP operation simultaneously), or SCP. From 4 to 16 SS7 signaling links may be defined by the user per SS7 board. These signaling links may either be user-defined timeslot/trunk associated with any of the DCOSS digital trunks, timeslots associated with the optional SS7 Dual T1/E1 trunk interface, or up to three links with the optional V.35 interface. If either the optional SS7 T1/E1 trunk interface or the optional V.35 interface is used, all other digital trunks associated with DCOSS (up to 16 trunks) will be capable of handling the SS7 voice channels.

Each user-defined SS7 signaling link also has a linkset association. Multiple SS7 signaling links may share a single linkset, thus providing SS7 link redundancy.

SS7 calls are identified using a Circuit Identification Code (CIC). The CIC may be an arbitrary value. DCOSS SS7 allows the user to custom associate a CIC to a timeslot/trunk and thus create a circuit to timeslot mapping table.

In addition to the link parameters and CIC mapping (as described above), all parameters, required for SS7 messages, may be modified within DCOSS.

MFC-R2 Protocol

The following are all parameters associated with the MFC-R2 protocol. These parameters may be modified and saved, within the DCOSS database, under a user-defined configuration.

Screenshot of MFC-R2 Protocol Parameter Configuration

Flow Control Parameters

Flow Control Parameters

Expected Number of DID digits
Expected Number of ANI digits
Number of DID before ANI
Calling Party Category

Ring/Busy Control

Ring Frequency 1 (Hz)
Ring Frequency 2 (Hz)
Ring ON-Time (ms)
Ring OFF-Time1 (ms)
Ring OFF-Time2 (ms)
Busy Frequency 1 (Hz)
Busy Frequency 2 (Hz)
Busy ON-Time (ms)
Busy OFF-Time (ms)
Ring/Busy Tone Ampl (IDU)
Compelled Tones Ampl (IDU)

Compelled/Flow Control Timers

Compelled Timers (sec)

Forward Tones Max ON-Time
Forward Tones Max OFF-Time
Inbound Compelled Cycle Timer

Flow Control Timers (msec)

Inbound, Release Guard Time
Inbound, Line Qualification Timers
During Idle
During Compelled Sequence
During Connected
Outbound, Line Qualification Timers
During Idle
During Compelled Sequence
During Connected
Outbound, Seizure Acknowledge Time
Outbound, Max Time before receipt of Group B backward tone and call answered (sec)
Outbound, Max Time between generation of Group II forward tone and detect Group B backward tone
Outbound, Time in which clearback, seen by outbound, is treated as remote hangup

Re-Answer Pulse (msec)

Time to wait for Re-Answer Pulse
Length of Re-Answer Pulse

Compelled Tones

Compelled Tones (select appropriate tone)

Backward Group A Tones
Send next DID
Send Group I category
Send next ANI
Send Group II tone (switch to Group B tone)
Backward Group B Tones
Indicate congestion
Indicate unallocated number
Indicate busy
Indicate line out of order
Forward Tones indicating end or non-availability
End of DID
End caller's category
End of ANI (caller id avail)
End of ANI (caller id restrict)
Backward Tones indicating acceptance of call
Call accepted in Group B (charge)
Call accepted in Group B (free)
Call accepted in Group A
Alternative tone for call accepted in Group B
Request or Indication Tones
Outbound tone in Group II
Default User Category (Group I)
After Category I, no ANI's avail
Backward Group B tone to reject incoming call
Backward Group A Tones
Repeat DID N-1
Repeat DID N-2
Repeat DID N-3
Repeat all DID's (restart dialing)
Backward Group C Tones (when collecting ANI's)
Rquest outbound to send DID's; send next DID
Rquest outbound to send DID's; repeat last DID
Inbound request the nature of the circuit
Inbound request if half-echo suppressor needed
Forward Group A tones that outbound plays
No satellite link in circuit
Satellite link in the circuit
Half-echo suppressor needed

Signaling Flags/Mask

Signaling Flags (On/Off)

Bit C - ON
Bit D - ON
Expect Metering Pulses on the A-Bit
Expect Metering Pulses on the B-Bit
Expect Metering Pulses on the C-Bit
Inbound Clearing Back signaled by a Release Guard
Half-Echo Suppression is needed in international
Bit Information
Ignore Bit Faults during Ring
Detect and Abort the Call
Next DID does not come
Pulse Congestion
Pulse Request for Group II Tone
Length of Delay after Outbound Protocol hangs up before place new call
No delay
400 ms delay
700 ms delay
1000 ms delay
Type of Bit Detector (definition of simultaneously bit transitions on a line)
5 ms

MFC-R2 Mask

Valid DID Tones in target country
Valid ANI Tones in target country
Valid Category Tones in target country
Valid Group II Tones in target country
Category Tones that imply no ANI follows

 Back to Digital Central Office Switch Simulator (DCOSS) Index Page

Home Page Sitemap Global Presence Email