If one initiator is connected to one target, there is no opportunity for contention with parallel SCSI, even this situation could cause contention. Each SAS device is connected by a dedicated link to the initiator, unless an expander is used. The SAS "bus" operates point-to-point while the SCSI bus is multidrop.( May 2014) ( Learn how and when to remove this template message) Unsourced material may be challenged and removed. Please help improve this article by adding citations to reliable sources in this section. This section needs additional citations for verification. For a SAS expander device, the SCSI port identifier and SCSI device name are the same SAS address. People sometimes call a SAS address a World Wide Name or WWN, because it is essentially the same thing as a WWN in Fibre Channel. People sometimes refer to a SCSI port identifier as the SAS address of a device, out of confusion. In SAS, both SCSI port identifiers and SCSI device names take the form of a SAS address, which is a 64 bit value, normally in the NAA IEEE Registered format. In Fibre Channel, the port identifier is a WWPN and the device name is a WWNN. One doesn't often see these device names because the port identifiers tend to identify the device sufficiently.įor comparison, in parallel SCSI, the SCSI ID is the port identifier and device name. In addition, every SAS device has a SCSI device name, which identifies the SAS device uniquely in the world. SAS devices use these port identifiers to address communications to each other. It is assigned by the device manufacturer, like an Ethernet device's MAC address, and is typically worldwide unique as well. Each SAS port in a SAS domain has a SCSI port identifier that identifies the port uniquely within the SAS domain, the World Wide Name.
0 Comments
Leave a Reply. |
Details
AuthorWrite something about yourself. No need to be fancy, just an overview. ArchivesCategories |