Specifications

Chapter 1 Introduction IPmux-11 Installation and Operation Manual
1-12 Functional Description
The maximum Ethernet throughput in static mode is calculated by:
Unstructured
bits 8*
n*47
data
TS*8000
*)
size frame
(














++
48476
44444443444444421
payloadoverhead frameVLAN
Structured
bits 8*
n*47
2
*500
pointer
1- 8)*(47
*8000
data
TS*8000
* )
size frame
(
























++
++
48476
48476
48476
44444443444444421
CAS
TSTS
payload overhead frameVLAN
• where VLAN is an optional field: if enabled it adds 4 bytes to the frame
overhead
• where payload = number of TDM bytes in frame, (48, 96, 144, 192, … 1440)
• where frame overhead = size of 46 bytes, include MAC, LLC, IP and UDP
layer
• where CAS is signaling (note: for structured mode only)
• where TS is number of configured time slots.
The result in both the equations is in bits per second [bps].
Round Trip Delay
The voice path round-trip delay is a function of all connections and network
parameters. The calculation for E1/T1 in each connection mode is described in the
following sections.
Round Trip Delay in Static Mode
(±2 µs) RTDelay
(
µ
s)
= 2 x [
NTS
n
47x
x 125 µs + PDVT buffer µs +1000 µs] + network round trip delay
• where n =
48
ebytes/framTDM
• where NTS = number of timeslots assigned; in unframed mode NTS is
constant: 32 for E1, 24 for T1
Reorder and Duplication of Ethernet Frames
IPmux-11 handles situations in the IP network where:
• Packets are reordered by the network
• Packets are duplicated.