2.5Gbps ethernet interface queries

[vinaykumarreddy]

Presently i am working on the different possible interface options for the 2.5Gbps MAC to PHY interface. Based on my study i came to know that there are couple of interfaces to interface MAC and PHY for 2.5Gbps. The interfaces are SGMII, SGMII+,HSGMII.

Questions:

1)What is the Maximum Speed of SGMII interface?

2)What is the Difference between SGMII+ and SGMII?

3)What is the difference between the SGMII and HSGMII?
4)Who are setting the standards for SGMII,SGMII+,HSGMII?

5)If cisco is setting the standards for the above interface could you please share the datasheet or electrical characterstics of the above interfaces.

Thanks in advance.

[balaji.bandi]

most of them are set by  IEEE standard :

https://en.wikipedia.org/wiki/Media-independent_interface

https://www.intel.com/content/www/us/en/architecture-and-technology/programmable/transceiver/protocols/pro-sgmii.html

Cisco point :

https://community.cisco.com/t5/networking-documents/difference-between-usgmii-and-usxgmii-and-why-usgmii-is-better/ta-p/4304438

[vinaykumarreddy]

Hi Balaji,

Thank you for the reply.

I have gone through the links which you shared but I need further information on the SGMII  interface.

1)The SGMII maximum supported speed is 1Gbps. In Broadcom BCM6757 SOC datasheet they are mentioned that SGMII interface of SOC is interfaced to 2.5Gbps PHY for the 2.5Gbps LAN. HOW the 1Gbps SGMII is different from the 2.5Gbps?

2)I have contacted the Broadcom about previous question but they replied that SGMII standard was set by the Cisco. In case if you have the SGMII interface app note or electrical specification document could you please share it with me.