3845 SFP module available on inbuild Gig port

[anasubra_2]

Hi All,

We are trying to figure out a command to identify whether a SFP is plugged in on the SFP port of the inbuild gigabit ethernet port on the Cisco 3845 router.

Any help is really appreciated.

Thanks

Regards

Anantha Subramanian Natarajan

[ralphcarter]

Do "show run int g0/0", under media type, if its states rj45, then its using the copper port.

Then do "show int g0/0" and see if its up. If the sfp is not inserted then it will show "media type is not connected". This will also tell you if it is rj45 or sfp. If an SFP is inserted, it will state media type is ZX,SX,etc.

[anasubra_2]

Hi Ralph,

Thank you very much and we were able to confirm that.We have one more question based on that,when we plugged in GLC-LH-SM,the "show interface" o/p showed media type as LX instead of LH.Is both are same ?

Any help to understand this would be appreciated.

Thanks

Regards

Anantha Subramanian Natarajan

[Sushil Kumar Katre · Accepted solution]

Hi Anantha,

LX and LH are two different standards with not much of a difference.

1000BASE-LX

1000BASE-LX is a fiber optic gigabit Ethernet standard specified in IEEE 802.3 Clause 38 which uses a long wavelength laser (1270 to 1355 nm), and a maximum RMS spectral width of 4 nm.

1000BASE-LX is specified to work over a distance of up to 5 km over 10 µm single-mode fiber.

1000BASE-LX can also run over multi-mode fiber with a maximum segment length of 550 m.

1000BASE-LH

1000BASE-LH is a non-standard but industry accepted term to refer to gigabit Ethernet transmission using 1300 or 1310 nm wavelength. It is very similar to 1000BASE-LX, but achieves longer distances up to 10 km over single-mode fiber due to higher quality optics. 1000BASE-LH is backwards compatible with 1000BASE-LX.[3]. Some vendors, like Cisco, use the term LH as a synonym for LX.

From Wiki - http://en.wikipedia.org/wiki/Gigabit_ethernet#1000BASE-LX

-> Sushil

[anasubra_2]

Hi Sushil,

Thank you very much for the reply.

Regards

Anantha Subramanian Natarajan