Справочник Пользователя для EMS Technologies Canada Ltd. HSD-X

• Disable the read receipt option 

• Send messages in text format not in HTML format and disable signatures 

to reduce message size

• Disable the “automatic download of message when in viewing 

 

panel” feature

• Increase the time period for automatic mail checks to reduce traffic

• Use IMAP4 mail protocol to allow for header retrieval only

Disable the “Save copy of send messages in the ‘Sent Items’ 
folder” option.

(4) Bonding Channel Cards in Two-Channel Card Systems

This section provides, as an example, detailed instructions on how to make bonded 
calls with a two-channel card HSD transceiver using a DIVA T/A ISDN modem.

Bonded calls are possible with HSD transceivers that have two channel cards 
installed. Bonded calls utilize both 64 kbps channels to provide a single 128 kbps data 
channel. The terminal adapter or router places two separate calls to combine the data 
transfer over both channels.

Although bonded calls provide a single 128 kbps channel, the actual link capacity is 
application and protocol dependant. Throughput on a Multilink PPP TCP/IP 
connection is typically 80 to 90 % of the link capacity (running Windows 2000®).

The system can only make internally bonded calls if both channels are available. If 
another device is using one of the B Channels, then the data call proceeds—but as 
a single channel call. 

If a bonded call is in progress, (using both B channels) the system is busy and denies 
all other calls until a channel is free.

In Multi-Channel configurations, the HSD transceiver channel cards cannot be 
internally bonded together with the HSD-X channel cards installed on the system; 
however, a Multi-Channel configuration, that includes an HSD-128 and two HSD-X 
extensions, is capable of up to 256 kbps data throughput—with the help of an external 
device such as a router or Ethernet hub.

(a) Bonding HSD Channel Cards using the ISDN Interface

If the HSD Transceiver has two channel cards, bonded calls provide the potential 
for higher throughput. For bonded calls, configure the terminal adapter and 
connections to use Multilink PPP as the protocol. 

Not all Internet service providers support Multi-link PPP. Contact your 
service provider for more information. 

If a bonded call is in progress, (using both B channels) the system is busy and 
denies all other calls until a channel is free.