Symbol Technologies MC3000 - Manual (Page 52)

MC3000 Integrator Guide 2-12
Daisychaining Ethernet Cradles
To connect several cradles to an Ethernet network, up to four (recommended maximum) Ethernet cradles may be daisychained. The
Speed LED and the Link LED on the Ethernet port 2 function in the same way as the Speed LED and the Link LED on the front of the
cradle.
To daisychain cradles:
1. Connect the first Ethernet cradle to power and to the Ethernet Switch as shown on Figure 2-5 on page 2-9 .
2. Connect power to the second Ethernet cradle.
3. Connect the daisychain Ethernet cable (either straight or twisted cable can be used) between Ethernet Port 2 of the first
cradle, and Ethernet Port 1 of the second cradle.
4. Connect additional cradles as described in Step 2 and Step 3. See Table 2-2 for bandwidth limations.
Figure 2-8. Daisychaining Four Slot Ethernet Cradles
Bandwidth Considerations when Daisychaining
Each cradle added to the daisychain impacts the bandwidth allocated to each of the inserted mobile computers, particularly when the
mobile computers attempt to send and receive at data rates that exceed the bandwidth provided to the chain (typically 100 Mbps). If
a mobile computer in a daisychained cradle does not use its bandwidth, that bandwidth is available to other inserted mobile
computers.
Table 2-2 shows allocated bandwidth (based on 100 Mbps) for the number of daisychained cradles, with each mobile computer
attempting transmission at the maximum data rate.
Table 2-2. Daisychaining Bandwidth
Daisychained Ethernet
Cradles
Bandwidth Allocation For Each
Ethernet Cradle (bits/sec)
Bandwidth Allocation For Each
Mobile Computer (bits/sec)
Cradle 1 100,000,000 20,000,000*
Cradle 2 20,000,000 4,000,000
Cradle 3 4,000,000 800,000
Cradle 4 800,000 160,000
Cradle 5** 160,000 32,000
Cradle 6** 32,000 6,400
Cradle 7** 6,400 1,280
* The maximum bandwidth capacity for the mobile computer is 12,000,000 bits/sec.
** Depending on the application, allocated bandwidth may not be adequate.
Ethernet Port 1 Ethernet Port 2
Link LED Speed LED