Brocade Inter-Switch Link (ISL) Trunking is an optional software product available for all Brocade 2 and 4 Gbit/sec Fiber Channel switches and directors. This technology is ideal for optimizing performance and simplifying the management of multi-switch SAN fabrics containing Brocade 1, 2, and 4 Gbit/sec switches and directors. When two or more adjacent ISLs are used to connect two switches, the switches automatically group the ISLs into a single logical ISL, or "trunk." The throughput of the resulting trunk can be anywhere from 4 Gbit/sec to as much as 32 Gbit/sec.
Increased performance with ISL Trunking
ISL Trunking is designed to significantly reduce traffic congestion in storage networks. To balance workload across all of the ISLs in the trunk, each incoming frame is sent across the first available physical ISL in the trunk. As a result, transient workload peaks are much less likely to impact the performance of other parts of the SAN fabric and bandwidth is not wasted by inefficient traffic routing. ISL Trunking can also help simplify fabric design, lower provisioning time, and limit the need for additional ISLs or switches.
Dynamic path selection for optimized performance
DPS augments ISL Trunking to provide more effective load balancing in certain configurations, such as routing data between multiple trunk groups - or in native connectivity configurations. This approach provides "transmit" ISL Trunking from Fabric OS to M-EOS products while M-EOS products provide transmit trunking, thereby enabling bidirectional trunking support. As a result, this combination of technologies provides the greatest design flexibility and the highest degree of load balancing.
Simplified management and design
In almost any network, management costs increase with complexity -rising with the number of elements being managed. With ISL Trunking, Brocade Fabric OS views the group of physical ISLs as a single logical ISL.
Higher availabilityProduct Highlights
The failure of a link in a route causes the network to reroute any traffic that was using that particular link - as long as an alternate path is available. ISL Trunking improves on this concept by helping to prevent the loss of the route. A link failure merely reduces the available bandwidth of the logical ISL trunk. In other words, a failure does not completely "break the pipe", but simply makes the pipe thinner. As a result, data traffic is much less likely to be affected by link failures and the bandwidth automatically increases when the link is repaired.
- Combines up to eight ISLs into a single logical trunk
- Optimizes link usage by evenly distributing traffic across all ISLs at the frame level
- Maintains in-order delivery to ensure data reliability
- Helps ensure reliability and availability even if a link in the trunk fails
- Optimizes fabric-wide performance and load balancing with Dynamic Path Selection (DPS)
- Simplifies management by reducing the number of ISLs required
- Provides a high-performance solution for network- and data-intensive applications