Specifications

Installation and Operation Manual Chapter 1 Introduction
IPmux-8/16 Ver. 6.00 Functional Description 1-25
You can configure the TDM bytes/frame parameter in N × 48 bytes, where N is an
integer from 1 to 30 (for E1/T1 or CT3) or 5 to 30 (for E3/T3).
If you configure TDM bytes/frame to a higher value, you will reduce the
IP/Ethernet overhead segment of the total packet, and thus can significantly reduce
the total Ethernet throughput.
On the other hand, packetization delay are increased; this contributes to a higher
end-to-end delay. This effect can be small and negligible when full E1 (or many
timeslots) is transferred but can be very significant when few E1/T1 timeslots are
transferred. In this case, the packetization delay and the intrinsic PDV, when
configuring a large value of TDM bytes/frame, can be very large and may exceed
the maximum PDVT (jitter) buffer on the receiving end. The tables below show the
throughput as a function of the TDM bytes/frame configuration for full E1 and full
T1.
TDMoIP Calculator supplied on the TDMoIP technical documentation CD can be
used for the following calculation:
• ETH/IP/MPLS bandwidth consumption,
• Packet per second rate
• Packetization delay,
• Maximum number of re-ordered packets
• End-to-end IPmux delay.
IPmux-16 with Two E3/T3 Cards
As the bandwidth for delivering two E3 or T3 over IP is more than 100 Mbps, two
Ethernet modules are needed to support two E3 or T3 TDMoIP modules. Each of
the Ethernet modules is used as an uplink to one of the E3/T3 ports. The Ethernet
module at slot number 1 is used as the uplink to the E3/T3 module at slot number
3; the Ethernet card at slot number 2 is used as the uplink to the E3/T3 module at
slot number 4.
End-to-End Alarm Generation
An end-to-end alarm generation mechanism exists in IPmux-8/16 to facilitate the
following alarms:
Unframed AIS will be transmitted toward the near-end PBX in event of:
• Far-end LOS, AIS
• PDVT underflow, overflow or packet loss.
Framed Timeslot / CAS configurable alarm pattern is transmitted toward
the near-end PBX in event of:
• Far-end LOS, LOF, AIS
• PDVT underflow, overflow or packet loss.