RAD Data comm IPmux-16 Manuel D’Utilisation
Chapter 1 Introduction
IPmux-16 Installation and Operation Manual
1-14 Functional Description
Table 1-4. Ethernet Throughput – Unframed T1
TDM
bytes/frame
bytes/frame
Frame
length
(bytes)
length
(bytes)
Over head
(bytes)
(bytes)
Over head
(%)
(%)
Packets
(per
second)
(per
second)
Throughput
(Mbps)
(Mbps)
48 94 46 96 4107
3.08
96 142
46
48
2054
2.32
144 190
46 32 1369
2.07
192 238
46 24 1027
1.95
240 286
46 19 821
1.87
288 334
46 16 685
1.82
336 382
46 14 587
1.78
384 430
46 12 513
1.76
➤
To calculate Ethernet throughput and intrinsic PDV as a function of
TDM bytes/frame:
Ethernet load (bps) = [(frame overhead (bytes) + TDM bytes/frame) × 8] × frames/second
Frame overhead = Ethernet overhead + IP overhead = 46 bytes
Frame/second =
Frame/second =
unframed:
5447/n for a full E1
4107/n for a full T1
framed:
8000Xk / (46.875 x n)
Where k = number of assigned timeslots
Where n =
48
e
bytes/fram
TDM
Round Trip Delay
The voice path round-trip delay, which is a function of all connections and
network parameters, is calculated for E1/T1 as follows:
network parameters, is calculated for E1/T1 as follows:
RTDelay
(
µ
s)
= 2 x (
NTS
n
48×
x 125 (µs) + PDVT buffer (µs) +500 (µs))+ Network round trip delay
Where n =
48
e
bytes/fram
TDM
Where NTS = number of timeslots assigned
in unframed E1 interface = 32
T1 interface = 24