Specifications

Installation and Operation Manual Chapter 1 Introduction
IPmux-24 Ver. 1.5 Functional Description 1-19
Where k = number of assigned timeslots
Where n =
48
ebytes/framTDM
The maximum Ethernet throughput is calculated by:
PCT
1
bits 8)
bytes) (in size frame
( ××+++
44444443444444421
payloadoverhead frameCW VLAN
Where:
• VLAN is an optional field: if enabled it adds 4 bytes to the frame overhead
• CW = control word (4 bytes)
• payload = number of TDM bytes in frame, (48, 96, 144, 192, … 1440)
• frame overhead = size of 46 bytes, include MAC, LLC, IP and UDP layer
The result is in bits per second (bps).
Pseudowire OAM
OAM connectivity is used to detect a valid connection (the remote IPmux will
confirm it recognizes the connection and that it is enabled). It prevents flooding
by a handshake. The control packets are run over a unique bundle number that is
used for this purpose. The control packets have the same packet overhead as the
traffic. The control packet uses the TDMoIP UDP number. OAM connectivity can
be enabled or disabled.
For control packets, the UDP checksum is neither calculated nor checked.
End-to-End Alarm Generation
An end-to-end alarm generation mechanism exists in IPmux-24 to facilitate the
following alarms:
• Unframed – AIS is transmitted toward the near-end PBX in event of far-end
LOS, AIS
• Framed – Timeslot/CAS configurable alarm pattern is transmitted toward the
near-end PBX in event of far-end LOS, LOF, AIS.
Trail-Extended Mode
To enhance fault condition reporting capabilities, remote IPmux-24 transfers RDI,
LOS, LOF and AIS conditions received from the remote E1 device to the local E1
device (see
Figure 1-15 ).
Figure 1-15. Fault Indication Transfer
Note