Powering Up

By Dave Greenfield  |  Posted 2008-08-18 Print this article Print

Neither vendor today has a solution for the 802.3at (POE Plus) standard in the tested platforms. Cisco offers its Enhanced POE on the 4500 series, and has indicated that it will release Enhanced POE on the 6500 series soon.

When we asked Cisco about supporting 802.3at in the 6500, we were told that customers will need to replace their power supplies to take advantage of their higher-powered Ethernet.

If this is the case, Cisco will need to introduce a new power supply, as the Cisco 8000w-the largest power supply the company currently makes available-won't be sufficient to power devices across all ports.

Extreme has not announced plans for 802.3at. Today, however, the company runs devices up to about 16.8W. The 8810 is limited to 7,200W.

Given the limitation of both vendors on this score, it seems likely that one or both will introduce a new chassis or new power supplies to accommodate the higher power requirements during the next year.

Complex Configuration

Ultimately, the biggest argument for the 6509-E is also its biggest challenge. There is no switch today on the market that can match the 6509-E's flexibility--not only in range of wiring options but also in the 6509-E's ability to accommodate a wide range of application modules. Indeed, in our conversation, Cisco touted the 6509-E as the "all-purpose" switch, not necessarily the one best-suited for a company looking solely for switching capacity. But it's this flexibility that makes the 6509-E's configuration so complex.

The Supervisor modules run either the IOS or CAT IOS operating system, depending on their age and the type of module. The problem is the wide array of switch code needed to support the services modules being used: "I've had a case when I had a NAM [Cisco Network Analysis Module], Flex WAN, IDSM-2 [Cisco Intrusion Detection Module] and a FWSM [Cisco Firewall Services Module] plugged into a single switch, and spent two weeks with the Technical Assistance Center upgrading code and fixing bugs until we discovered the correct code to use," said Fistler.

Organizations are thus advised to negotiate contracts with their integrators on project price and not installation time. This is always a good idea, but particularly so when expecting to configure the 6509-E with service modules.

On the other hand, organizations looking for pure switching may want to consider the Extreme solution or the Cisco 4500.

The Extreme switches offer more capacity for a lower price than the 6509-E, while providing the ability to undersubscribe edge ports. Extreme customers can also reduce their recurring costs by settling for less aggressive replacement times on their service contracts.

Conceivably, Cisco customers could do the same, but then they run into the problem of having to spare separate Supervisor and wiring modules for the core and access layers. Extreme's switches avoid that problem by using the same modules.

Dave Greenfield is a 20-year networking veteran and the principal of Strategic Technology Analytics.


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