TRANSip consists of:
Let's look at usage of the following in a REDCOM system:
There are 2,048 ports in each HDX•C shelf, SLICE 2100 or SLICE IP. There are 512 timeslots in each SLICE 2100 or SLICE IP unit. In the HDX•C, each shelf can have 512, 1024, or 2048 timeslots, up to a maximum of 4,096 timeslots per HDX•C system.
There are up to 3,000 IP registrants in each TRANSip equipped HDX shelf and SLICE IP, and up to 2,000 IP registrants in each SLICE 2100. These registrants do not use any ports unless they are active, meaning in a call state. These IP registrants only use timeslots if they need to access system services such as conferencing, announcements, or connecting to a TDM / analog interface (HDX•C /SLICE 2100 only).
The timeslots and ports that are used for IP calls are located in the MSC board. One MSC board can have up to 128 timeslots. Additional boards should be added to the system if more timeslots (i.e. IP to TDM conversions) are needed. Below are two examples to further clarify the shared resources in the HDX•C and SLICE 2100.
In this example, an IP phone calls another IP phone using an HDX•C as the call controller. These phones are registered in the HDX•C, thus they occupy 2 of the possible 3,000 registrations in this HDX•C shelf. They do not occupy any port until they call each other. The moment they call each other, each of them occupies a system port. However, since there is no IP to TDM conversion, no timeslots are used.
Total resources used in this example:
In this example, an IP phone calls an analog phone using a TRANSip-equipped HDX•C as the call controller and media gateway. The IP phone is registered to TRANSip and occupies 1 of the possible 3,000 registrations in the HDX•C shelf. The moment the IP phone calls the analog phone or vice versa, a timeslot is used in the MSC board for media gateway functionality.
The total resources used in this example:
Resource planning may be somewhat challenging due to the number of variants. The communication experts at REDCOM will be more than happy to help with resource planning if you have any questions or concerns.
TDM circuit-switched phones and other TDM equipment are physically connected to the HDX•C or SLICE 2100. This gives some physical assurance that the device is authorized.
An IP telephone is not connected physically to a TRANSip-equipped system. Rather, it uses the data network to send a SIP message to the system to be “registered”. Because IP phones are not physically connected to the TRANSip’s SIP Call Controller, it must ensure the IP phone is, indeed, an authorized device, and not one that is masquerading for the purpose of unauthorized use of TRANSip’s services. This is accomplished by programming the phone with the IPv4 or IPv6 address of the TRANSip equipped system, specifying a SIP username, and assigning an optional pre-arranged password. The SIP username and password are exchanged and validated as part of the registration process. Registration typically occurs when the phone is connected to the data network and powered up, and then is repeated at scheduled intervals.
Once an IP phone is successfully registered, TRANSip’s SIP Call Controller may dispatch calls to it and accept requests for service from it. When the IP phone is “idle”, as long as the registration has not expired, TRANSip remains aware of the phone, but it does not occupy any ports or timeslots on the system.