cat6500 module question

[julxu]

Greeting

Could anyone advice me that is there capability dramatic difference between module WS-X6516-GBIC and module WS-X6748-GE-TX? Of cause they are use different adapter, but how about other feature?

The reason I ask, because I current use a critical device on WS-X6516-GBIC, and there is small packet drop on output queue, if I change it to use WS-X6748-GE-TX, if it will improve?

Any comments will be appreciated

Thanks in advance

[Jerry Ye · Accepted solution]

The WS-X6748-GE-TX will definitely provide better performance over the WS-X6516-GBIC. It has much larger buffer, and QoS support. From the data sheet, the WS-X6748-GE-TX has 1.3MB buffer per port, while the WS-X6516-GBIC has 512KB buffer per port.

Please check out the following data sheets

http://www.cisco.com/en/US/prod/collateral/switches/ps5718/ps708/product_data_sheet0900aecd801459a7.html

http://www.cisco.com/en/US/prod/collateral/switches/ps5718/ps708/product_data_sheet0900aecd8017376e.html

HTH,

jerry

[Joseph W. Doherty]

Jerry's references might note this, but some important differences between the two module cards, the 6516-GBIC has dual CEF256 (8 GB) fabric connection, the 6748 (TX or SFP) has dual CEF720 (20 GB) fabric connections. The 6748's optional DFC supports a higher forwarding rate (48 Mpps vs. 24 Mpps) than the 6516-GBIC optional DFC.

As to your question about packet drops, depends on the nature of the drops. Drops, in theory, is normal with any oversubscription. Deeper queues/buffers might absorb transient oversubscription with less drops.