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The H802EDTB board can work in the VOICE mode.

In the case of TDM SHDSL in the VOICE mode, the H802EDTB board needs to be configured with the working sub-mode: service mode or transparent transmission mode.

l Service mode

Each G.SHDSL port and E1 port are independent ports, on which the SPC, PRA service, port rate, or port mode can be configured.

l Transparent transmission mode

The H802EDTB board automatically connects the Nth SHDSL line with the Nth E1 line to transparently transmit the 2M data. The E1 port is in the UNFRAME format. The clock locks the Nth E1 line clock. Therefore, every E1 line has its independent clock. In the transparent transmission mode, the SPC and PRA services cannot be configured.

5.3.6 Narrowband Data Private Line Service Applications

The narrowband data private line service is mainly demonstrated in expanding the reach of DDN nodes. TDM SHDSL for expanding the reach of DDN nodes is a mainstream method supported by the integrated access equipment to provide the DDN service. On the CO side, the integrated access equipment connects to the DDN node through E1; on the user side, the TDM-capable SHDSL modem provides the TDM SHDSL (E1) port to implement N x 64 kbit/s private line access and at the same time achieves private line interconnection by supporting the V.35-capable router, as shown in Figure 5-5.

Module

Feature Description 5 SHDSL Access

Figure 5-5 Narrowband data private line service applications

Router FE

FE

Router

SHDSL modem

SHDSL modem

MA5600T/

MA5603T V.35

V.35

TDM SHDSL (E1)

TDM SHDSL (E1)

E1

The MA5600T/MA5603T connects to the DDN node in the following two ways:

l Transparent transmission l Aggregation

Figure 5-6 shows how the MA5600T/MA5603T connects to the DDN node in the transparent transmission mode: The H802EDTB board connects upstream to the DDN network through E1 and connects downstream to the SHDSL modem through SHDSL.

Figure 5-6 Connection to the DDN (in the transparent transmission mode)

E1

E1 E1

SHDSL

SHDSL SHDSL

E1 Port

SHDSL Port

...

...

H802 EDTB

Router SHDSL modem E1

SHDSL

The working sub-mode of the H802EDTB board of the MA5600T/MA5603T is set to the transparent transmission mode. In this mode, the H802EDTB board automatically maps E1 ports 0-15 to SHDSL ports 16-31 to transparently transmit data.

NOTE

In addition, the clock source for every E1 port on the H802EDTB board comes from the E1 line clock and the clock source for an SDHSL port keeps synchronized with its corresponding E1 port.

Module

Feature Description 5 SHDSL Access

Figure 5-7 shows how the MA5600T/MA5603T connects to the DDN node in the aggregation mode: The H802EDTB connects upstream to the DDN network through E1 and connects downstream to the SHDSL modem through SHDSL.

Figure 5-7 Connection to the DDN (in the aggregation mode)

TSn

TS0 TS 31

E1 Port

SHDSL Port

...

H802 EDTB

Router SHDSL modem

TS1 ... TSm

64K ...

64K 64K ... 64K

N*64K M*64K

E1

SHDSL SHDSL

...

...

...

32*64K 32*64K

N*64K M*64K

An SHDSL port supports only framed N x 64 kbit/s, that is, the SHDSL modem still sends 32 x 64 kbit/s to the equipment (certain timeslots of the 32 timeslots may not carry data because N may be smaller than 32). In this way, The H802EDTB board aggregates certain timeslots in 32 x 64 kbit/s for multiple SHDSL ports and then sends them upstream to the DDN.

NOTE

That is, N x 64 kbit/s is input to the SHDSL modem and the modem outputs E1 frames with 32 timeslots. The equipment aggregates certain timeslots of multiple E1 frames into a same E1 port and then sends them upstream to the DDN.

The working sub-mode of the H802EDTB board of the MA5600T/MA5603T is set to the service mode. In addition, the frame format of the E1 and SHDSL ports are configured to UNFRAME, and SPCs are set up for timeslots between N x 64 kbit/s for multiple SHDSL ports and E1 ports.

This achieves the aggregation of multiple N x 64 kbit/s into E1, that is, timeslot channels of different lines are multiplexed to the same E1 upstream port, thereby saving E1 resources.

5.3.7 PRA Carrying Applications

Figure 5-8 shows the long-distance access of the PBX to the IP network for carrying the PRA service.

Module

Feature Description 5 SHDSL Access

Figure 5-8 PRA carrying applications

PBX TDM SHDSL modem

MA5600T/

MA5603T

TG

Softswitch/IMS

H.248/SIP RTP E1/

PRA

E1 TDM SHDSL

l The PBX provides E1 in the upstream direction.

l The SHDSL modem implements the E1-to-SHDSL conversion and connects upstream through SHDSL to the SHDSL port on the H802EDTB board of the MA5600T/

MA5603T.

l The MA5600T/MA5603T connects upstream to the IP network.

l The working mode of the H802EDTB board of the MA5600T/MA5603T is configured to the service mode.

l The signaling mode of the SHDSL port is configured to CCS. In addition, the D channel signaling of the PRA is transmitted in timeslot 16 and timeslot 0 is used for frame synchronization.

By using SHDSL, the MA5600T/MA5603T provides long-distance transmission to implement long-distance access of the MA5600T/MA5603T and PBX.

5.3.8 Glossary, Acronyms, and Abbreviations

Glossary

Glossary Explanation

Port binding Port binding is to bind two or more ports as one port for use, thereby increasing

bandwidth.

Timeslot A timeslot represents a communication

channel and is allocated to one user. (Time is segmented into periodical non-overlapped frames and every frame is further segmented into several non-overlapped timeslots.) Module

Feature Description 5 SHDSL Access

Glossary Explanation

Common channel signaling Common channel signaling (CCS) is a method of transmitting a group of voice signaling over the public data link in the form of messages, where the signaling channel and the service channel are completely separate.

China's No. 7 signaling system is a CCS system.

Channel associated signaling Channel associated signaling (CAS) is a method of transmitting signaling over the corresponding voice channels. China's No. 1 signaling system is a CAS system.