Ethernet and Spanning Tree Protocol
Ethernet and Spanning Tree Protocol
After researching Cisco resilience solutions and HP IRF resilience solutions I have written this summary report to answer the following 3 questions as per assignment;
QUESTION 1 – What are the three primary differences between Cisco layer 2 network resiliency and HP IRF resiliency?
The first obvious difference is the protocols that they use. Cisco uses Spanning Tree Protocol (STP) while HP IRF uses the Link Aggregation Control Protocol. The second difference lies in the architecture being used. Cisco uses a mesh of network switches, linked to other switches in the aggregation layer, which in turn is linked to the core. This mesh type application of switches provides multiple paths for network traffic to flow. What this means is that if one link in the traffic flow or a switch goes down, traffic can continue to flow using an alternate path. HP uses a loop-free, non-blocking architecture. This is designed to keep all links active, enabling highly efficient, high bandwidth connectivity throughout the switching plane. The third major difference is in their prospective bandwidths. HP has high bandwidth connectivity due to IRF’s loop-free, non-blocking architecture. This is designed to keep all links active, enabling highly efficient, high bandwidth connectivity throughout the switching plane.
QUESTION 2 – What are two or three advantages of each company’s layer 2 network resiliency solutions?
Cisco features cost-effective components while achieving full redundancy, load balancing and full scalability.
HP’s IRF (Intelligent Resilient Framework) is designed to combine the benefits of box-type devices (simple, standalone switches for example) and chassis-based distributed devices, such as a blade switch. The argument is that box-type devices are cost-effective, but can be less reliable and less scalable, and are therefore unsuitable for critical business environments. In contrast, chassis-based devices tick all these boxes but are more expensive and considered to be more complex to deploy and manage. With IRF, then, HP is looking to merge the benefits of both approaches into one. IRF allows you to build an IRF domain, seen as one, big, logical device.
QUESTION 3 – What are two or three disadvantages of each company’s layer 2 network resilience solutions?
The biggest disadvantage to Cisco is their use of mesh interlinked switches. This mesh type application of switches provides multiple paths for network traffic to flow. What this means is that if one link in the traffic flow or a switch goes down, traffic can continue to flow using an alternate path. This type of mesh interlinked switches uses Spanning Tree Protocol (STP) to detect and prevent loops. A loop occurs when there are multiple active paths to the same switch and this causes the system to crash. The disadvantages associated with HP’s IRF Resiliency are said to be poor performance because it blocks all parallel paths except the one it has selected as active. Technicians have complained that even when the network is operating normally STP actually reduces the effective bandwidth.
QUESTION FOUR – Which solution do you recommend for the Marketing Company and why?
My recommendation would be to use the Cisco Layer 2 resiliency solution. The Market Company is already flooded with Cisco hardware which needs to use the Spanning Tree Protocol (STP). STP has been shown to reduce the larger band width that is HP’s main advantage. HP’s IRF is also known to have poorer performance because it blocks all parallel paths except the one it has selected.