September 10th, 2009 | |
Posted in Storage
First of all, let me apologise in advance for confusing you with this blog. It is quite probably going to be completely wrong – but i’m going to try anyway
Recently i joined a storage company and as such i have been cramming Fibre channel as much as i can. Below is what i understand to be the main differences beetween the 3 main different types of Fibre Channel topologies if you will:
FC-AL: Fibre Channel Arbitrary Loop. Much like a token ring topology, uses loops and and WWDN (WorldWide Device Numbers) to transmit data. Very old topology used as it was cheaper and more economical. Problems occur when the ring is broken, or when chatter occurs by a faulty host which causes all hosts in the FCAL to back off and wait.
FC-P2P – Like a PC plugged into another PC, P2P allows one host to communicate with the other host over a dedicated medium. This solution is effective and economical but again it is not very scalable especially in a multi-node environment such as a corporation etc.
FC-SW: Fibre Channel Switched Fabric, this is much like the modern day ethernet, whereby nodes communicate with each other using a common device such as a switch (Infiniband switch for example). The Host-bus adapters (HBA’s) connect to the switch and allow nodes to communicate with the other nodes via the switch, creating “fabrics” (i think). This is obviously a smarter solution as it is scalable and more flexible but is very expensive.
Tags:
FC,
FCP,
Fibre Channel