LAN Phy or WAN Phy?

kris-andrews · ‎01-20-2011

Hi All,

Can someone please clarify the difference between 10Gbps LAN Phy and WAN Phy?

Is there is a preference between using either/or?

Alexei Kiritchenko · ‎01-20-2011

Hello,

We can think of 10GE LAN as a usual Ethernet we used to see.

10GE WAN uses SONET/SDH framing instead and hence can be directly connected to OC-192c/STM-64 interfaces at a carrier network. For diagnostics 10GE WAN PHY makes use of the SONET overhead bits to detect :

- Loss of signal

- Coding violations

- Framing errors/ loss of frame

- Errored seconds

- Severely errored seconds

- Loss of synchronization (not needed) • Same Error/ performance monitoring

- B1, B2, B3

- J0, J1

Same Defect/ Alarms

- FEBE

- RDI

- AIS

…

Regards,

/A

smailmilak · ‎03-30-2012

Thank you Alexei for the clarification.

So this means that if we have a line card with WAN PHY then we can use G.709 optical SFP/XFPs with FEC, and with LAN PHY we don't have features like loss of signal, framing errors etc?

Alexei Kiritchenko · ‎04-01-2012

That is not entirely correct. There is LAN, WAN and G709 encapsulations. WAN and G709 are not the same. WAN is based on SONET and G709 is a separate standard for optical transmission (primarily for DWDM).

FEC is available with G709 only.

LOS is very general alarm, LAN ports support it too.

So your XFP and LC should explicitly support G709 in order to have FEC.

Regards,

/A

smailmilak · ‎04-01-2012

Thank you for the clarification.