Professional Service Agreement
The following pre-installation Professional Service Agreement is to be filled in for any professional service installation.
All the terms must be mutually agreed upon by the customer and Sangoma Technician prior to work.
A copy of the NSG SS7 Professional Service Agreement can be downloaded here:
-> NSG SS7 Professional Service Agreement
Included in the agreement document is an "SS7 Site Survey" which details all the SS7 network components the Sangoma Technician requires the customer to fill in.
The components will be provided by the SS7 telco to the customer.
example of the SS7 Site Survey:
Details on each heading seen in blue are described below
Wanpipe #
The Wanpipe # is unique number assigned to each port and is used to easily identify the port.
The number will be used for the wanpipe configuration file (/etc/wanpipe/wanpipeX.conf) as well as for the interface name (wxg1).
This value does not need to be filled in as it will be filled in my the installation technician.
T1/E1 Cfg
This section is used to briefly describe the settings needed for the physical layer/layer 1.
The structure of the field is: Line Media/Line Clocking/Line Framing
Line Media values are: T1 or E1
Line Clocking values are: N(ormal) or M(aster)
Line Framing values are: ESF, D4, CRC4, and NCRC4 (aka double frame)
FTDM Span #
The FTDM span value is a virtual number assigned to every port and is used to uniquely identify the port in the SMG cli.
This value does not need to be filled in as it will be filled in my the installation technician.
Sig Channel
This section indicates on which time slot on the specified port a signaling link will be.
Most commonly a signaling link will be on time slot 1 or 16.
The telco should provide you with this information.
Error Type
This section indicates the type of layer 2 (MTP2) error correction the signaling on this port will use.
There are 2 types of Error Correction: basic or pcr.
The telco should provide you with this information but PCR error correction is always used on links that will be transmitted on satellite connections and BASIC for all other types of connections
LSSU Length
This section indicates the length of LSSU frames on the signaling link.
The length of an LSSU frame is either 1 or 2.
The telco should provide you with this information.
SLC (Signaling Link Selection Code)
This section indicates the SLC value for the signaling link on this port.
The SLC is a value between 0-15 that unique identifies this signaling link.
Normally your first link will use 0, the second link will use 1, the third link will use 2, etc
The telco should provide you with this information.
SSF mtp3/isup
This section indicates what SSF (Sub-Service Field) values this signaling link will use for the MTP3 traffic and ISUP traffic.
The possible values are: int (0), spare (1), nat (2), res (3).
Normally the value for MTP3 and ISUP layers will be the same but they can also be different.
The telco should provide you with this information.
APC
This section indicates the APC (Adjacent Point Code) for the signaling link on this port.
The APC is the point code of the system on the other end of the signaling link.
The telco should provide you with this information.
DPC
This section indicates the DPC (Destination Point Code) for the CICs on this port.
The DPC is the point code of the SSP that the CICs are connected to.
The telco should provide you with this information.
CIC Base
This section indicates the CIC base value for the CICs on this port.
The CIC base is the CIC value for the first channel on this port.
The telco should provide you with this information.
Audio Channels
This section indicates which time slots/channels on this port will be used to carry voice traffic.
It is not un-common for channel 16 on ITU installs to not carry voice traffic and not carry signaling traffic.
The telco should provide you with this information.
NADI clg/cld
This section indicates what value of NADI (Nature of address indicator) will be used for calling and called numbers.
The telco uses this information to route the call as either a national or international number as ISUP does not allow you to use "+" in the called number string.
If not all calls will use the same value leave this field blank and your technician will enable per call control of these values.
Commonly used values are: national (3) or international (4).
More information on this option can be found here.