Ace ACE-3105, Инструкция по установке и эксплуатации

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Chapter 1 Introduction Installation and Operation Manual
1-16 Functional Description ACE-3105, ACE-3205 Ver. 5.2
ACE-3105, ACE-3205 support up to 8 CES bundles per E1/T1 port and up to
32 bundles in total.
To compensate for the jitter caused by the packet-switched network, each TDM
stream has a jitter buffer of up to 32 milliseconds. In addition, since the order of
frames is not predictable over Ethernet networks, ACE-3105, ACE-3205 can
optionally perform reordering of received and transmitted packets.
Clock Recovery
Using a dedicated clock recovery component and a software license, ACE-3105,
ACE-3205 can adaptively recover the clock stream from a packet-switched
network via the DSL ports, according to the G.8261 requirements. Alternatively,
NTR clock recovery can be used in SHDSL, as explained below.
Adaptive Clock Recovery
The adaptive clock recovery is performed directly from the PSN using a dedicated
pseudowire that originates from the clock distribution device, and then through
the DSLAM and DSL uplinks of ACE-3105, ACE-3205. The clock stream is
forwarded by ACE-3105, ACE-3205 to the BTS and Node B over Ethernet or N x
E1/T1 interfaces, as shown below.
Figure 1-12. Adaptive Clock Recovery
Adaptive clock recovery is supported over SHDSL or ADSL2+ interfaces, yet it
requires dedicated clock recovery hardware and software license.
NTR Clock Recovery
In NTR clock recovery, the DSLAM receives the clock stream via its BITS interface,
and then forwards it via the DSL line as an NTR clock stream towards ACE-3105,
ACE-3205. The DSLAM receives the clock stream from either:
• A GPS system
•
An SDH connection
• A clock recovery gateway (such as ACE, located near the DSLAM).