Specifications

Installation and Operation Manual Chapter 1 Introduction
IPmux-24 Ver. 1.5 Functional Description 1-11
Adaptive Timing
When a common clock is not available on all the ends of the network, one of the
IPmux-24 devices is configured to work in loopback timing, while the other IPmux-
24 device is configured to work in adaptive timing (see
Figure 1-5 ).
Figure 1-5. IPmux-24 in Adaptive Timing Mode
In leased line applications, the carrier does not know which side provides the
source clock. To ensure correct clock distribution, IPmux-24 units working
opposite each other can be both configured to adaptive clock.
As the clock is recovered twice, it is more sensitive to interferences introduced by
the network.
Figure 1-6. IPmux-24 in Adaptive-Adaptive Timing Mode
Frame Format
Network encapsulation method depends on packet-switched network type (IP or
MPLS) and pseudowire standard (TDMoIP, CESoPSN, SAToP or HDLCoPSN).
IP Encapsulation (MPLS and IP Networks)
The Ethernet frame sent by IPmux-24 is a UDP datagram that transfers E1/T1
payload bytes over IP over Ethernet (UDP payload + UDP header + IP header +
Ethernet header). The UDP payload is equal to TDM bytes per frame
(TDM bytes/frame configuration).
Table 1-1 specifies the structure of the
different headers, special fields, and the payload in the Ethernet packet.
CRC TDM Payload CW UDP IP ETH
Figure 1-7. TDMoIP Frame Structure
Note