Hello All,
I am trying to figure out how the media converter for a copper to fiber Ethernet link works. To be more specific, how does the conversion of four diff pairs get brought to two. I'm guessing it's through the following process but am not sure.
You start with a PC connected to a router containing the MAC. The MAC addresses the data, sends it through it's media independent interface (MII) to a physical layer chip (PHY), and the transmits across the media dependent interface (MDI) RJ-45 port to a target machine. Once through the cable it hits the MDI on the other PHY, which then converts it to MII where the target machine gets the signal as usable data.
In order to use the optical fiber however, those four lanes need to be compressed to two (Tx, Rx). To do this a PHY uses RGMII or SGMII, instead of the lower IEEE standards which use the basic MII, in an effort to multiplex the lanes together.
So in a media converter for GigE, they'd have some sort of controller to get status flags and generate codes, power stuff, and a PHY capable of RGMII or SGMII. A link would then have two of these media converters where you transmit/receive optical information through RGMII/SGMII and then shunt that back to copper on MDI side of the PHY which gets sent to the MDI side of the machine's PHY. That then outputs in GMII for the machine to use.
The optical drivers are stored in SFP Modules.
If anyone could confirm this or correct the process I have outlined that would be wonderful and I'd be thrilled! If I've inserted confusing statements that need clarification let me know, I'll try my best to correct them.
- Mezzer26
I am trying to figure out how the media converter for a copper to fiber Ethernet link works. To be more specific, how does the conversion of four diff pairs get brought to two. I'm guessing it's through the following process but am not sure.
You start with a PC connected to a router containing the MAC. The MAC addresses the data, sends it through it's media independent interface (MII) to a physical layer chip (PHY), and the transmits across the media dependent interface (MDI) RJ-45 port to a target machine. Once through the cable it hits the MDI on the other PHY, which then converts it to MII where the target machine gets the signal as usable data.
In order to use the optical fiber however, those four lanes need to be compressed to two (Tx, Rx). To do this a PHY uses RGMII or SGMII, instead of the lower IEEE standards which use the basic MII, in an effort to multiplex the lanes together.
So in a media converter for GigE, they'd have some sort of controller to get status flags and generate codes, power stuff, and a PHY capable of RGMII or SGMII. A link would then have two of these media converters where you transmit/receive optical information through RGMII/SGMII and then shunt that back to copper on MDI side of the PHY which gets sent to the MDI side of the machine's PHY. That then outputs in GMII for the machine to use.
The optical drivers are stored in SFP Modules.
If anyone could confirm this or correct the process I have outlined that would be wonderful and I'd be thrilled! If I've inserted confusing statements that need clarification let me know, I'll try my best to correct them.
- Mezzer26