Specifications

Chapter 1 Introduction Installation and Operation Manual
1-6 Functional Description MiTOP-E1/T1 Ver. 1.0
Packet Creation Time (PCT)
When MiTOP-E1/T1 builds a frame, a packetization delay is introduced. The
packet creation time is different for the different payload encapsulation
methods. It is calculated according to the following formulas:
CESoPSN
PCT (ms) = N × 0.125
Where:
N = Number of TDM frames in packet
SAToP
PCT (ms) =
TS
0.125N ×
N – Number of TDM bytes in packet
TS – Number of timeslots in one frame (32 for E1 or 24 for T1)
Round Trip Delay
The voice path round-trip delay is a function of all connections and network
parameters.
(±2 msec) RT Delay
(msec)
= 2 × (PCT + Jitter Buffer Level) + network round trip delay
Ethernet Throughput
Increasing payload size reduces the ratio between the TDMoIP/IP/Ethernet header
segment in the packet and the payload, thus reducing the total Ethernet
throughput.
On the other hand, packetization delay is increased; this contributes to a higher
end-to-end delay. This effect can be small and negligible when a full E1 (or many
timeslots) are transferred, but can be very significant when few timeslots are
transferred.
Configuring the TDM bytes per frame (TDM bytes/frame) parameter has an impact
on Ethernet throughput (bandwidth or traffic traveling through the Ethernet).
This parameter controls the number of TDM bytes encapsulated in one frame.
The calculations depend on the payload encapsulation type: CESoPSN or SAToP.
• CESoPSN: The TDM frame in packet parameter can be configured to 2–47 (E1),
2–60 (T1)
• SAToP: The bytes in packet parameter can be configured to 30–1476.