PEB2096 SIEMENS [Siemens Semiconductor Group], PEB2096 Datasheet - Page 32

• Manufacturer Part Number: PEB2096
• Description: Octal Transceiver for UPN Interfaces OCTAT-P
• Manufacturer: SIEMENS [Siemens Semiconductor Group]

3.6
Decentralized D-Channel processing can be realized by the use of only one multiplexed
HDLC-Controller, which is integrated with a D-channel Arbiter in the ELIC, PEB 20550.
Typically the D-channel load has a very bursty characteristic. Taking this into account,
the ELIC provides the capability to multiplex one HDLC-controller among several
subscribers. This feature results in a drastical reduction of hardware requirements while
maintaining all benefits of HDLC based signaling (figure 17).
A D-channel arbiter is used to assign the receive and transmit HDLC-channels
independently to the subscriber terminals.
In downstream direction the arbiter links the transmit channel to one or more (broadcast)
programmable IOM-2 D-channels (ports).
In upstream direction the arbiter assigns the HDLC-receive channel to a requesting
subscriber and indicates to all other subscribers that their D-channels are blocked, using
a control channel.
This configuration supports full duplex layer-2 protocols with bus capability e.g. LAPD or
proprietary implementations. Consequently no polling overhead is necessary providing
the full 16-kbit/s bandwidth of the D-channel for data exchange.
Figure 17
D-Channel Handling with only one Multiplexed HDLC-Controller (SACCO-A)
Semiconductor Group
D-Channel Handling
IOM -2
Interface
µP
R
D Channel
SACCO CH-A
SACCO CH-B
32
B Channels
ARBITER
D Channel
Controlling
ELIC
EPIC
R
R
ITS05808
PCM
Highway
Signaling
Highway
PEB 2096
01.96