Fujitsu MBC2073RC Manual Do Utilizador

28 

C141-C013 

A connection is a temporary association between a SAS INIT port and a SAS 
TARG port.  During a connection all dwords from the SAS INIT port are 
forwarded to the SAS TARG port, and all dwords from the SAS TARG port are 
forwarded to the SAS INIT port. 

A connection is pending when an OPEN address frame has been delivered along a 
completed pathway to the destination phy but the destination phy has not yet 
responded to the connection request.  A connection is established when an 
OPEN_ACCEPT is returned to the source phy. 

A connection enables communication for one protocol: SSP, STP, or SMP.  For 
SSP and STP, connections may be opened and closed multiple times during the 
processing of a command. 

The connection rate is the effective rate of dwords through the pathway between a 
SAS INIT phy and a SAS TARG phy, established through the connection request.  
Every phy shall support a 1,5 Gbps connection rate regardless of its physical link 
rate. 

One connection may be active on a physical link at a time. If the connection is an 
SSP or SMP connection and there are no dwords to transmit associated with that 
connection, idle dwords are transmitted.  

The number of connections established by a SAS port shall not exceed the number 
of SAS phys within the SAS port (i.e., only one connection per SAS phy is 
allowed). There shall be a separate connection on each physical link. 

If multiple potential pathways exist between the SAS INIT port(s) and the SAS 
TARG port(s), multiple connections may be established by a SAS port between 
the following: 

a)  one SAS INIT port to multiple SAS TARG ports; 

b)  one SAS TARG port to multiple SAS INIT ports; or 

c)  one SAS INIT port to one SAS TARG port. 

Once a connection is established, the pathway used for that connection shall not 
be changed (i.e., all the physical links that make up the pathway remain dedicated 
to the connection until it is closed).