Medium Access Control (MAC) and Physical Layer (PHY) - CISE

4-June-07 P1901_PRO_016_r0
Polling Token addressed
to Slaves 1,2 and 3
Master
TX
Slave1
TX
Slave2
TX
Slave3
TX
Polling PPDU
IPPDUS1
Time
Size Poll
Window
Submission page 100 UPA-OPERA
Polling
Slot 1
S
O
T
Figure 32 Polling scheme
Offset Poll
Window
Size Poll
Window
Polling
Slot 2
Offset Poll
Window
Size Poll
Window
Polling
Slot 3
As described in 4.2.1, there are two types of Polling Tokens transmitted by a master to CPEs:
• Active Polling Token
• Alive Polling Token
These Polling Tokens are identified by the Polling Type field (see 4.4.2.4, Polling Token).
S
O
T
IPPDUS1
Note: Active Polling Tokens provide an Idle CPE with the ability to recover the Active state and get
transmission opportunities. The master transmits data tokens only to those slaves that are considered Active.
Alive Polling Tokens provide the master with the ability to detect slaves with no activity (e.g.: turned off).
These ones become Unregistered and are not polled anymore.
4.3.6 TDR Polling Frame
As described in 4.3.5, master shall periodically poll its Idle TDRs and give them opportunity to poll their own
Idle slaves (CPEs and/or TDRs) and transmit Access Frames. TDR Polling Frames have the same format as a
Data Frame except for the last symbol, which is a TDR Polling Token instead of a Data Token. TDR Polling