Midspan(mode b) and endspan (mode a) ?

MacAmb77

Young grasshopper
Nov 29, 2021
34
3
Iraq
Hello guys whats up?
Regarding a poe/none poe PSE(POE switch etc..)

So if i have a poe switch and a poe ip camera does it matter the Ethernet cable terminator Mode ?or i should use Mode A ?
because i always Mode B
Or i can use any mode?
Or it does matter ? If it does,does the manufacturer provide info on which mode is used for cabling?.

Thanks ..
And sorry for a noob question i am new to Networking.
 
If I understand correctly, you're referring to the method of terminating the RJ-45 connection. If so, just insure both ends are the same.
The U.S. is mostly T-568B as follows:

RJ45-Pinout-T568B_med.jpg
 
Yes i know that.
But my question was when do we use Mode A and Mode B ?
Do you use Mode A or Mode B when a product vendor like a poe switch provides info on datasheet on which mode you use?
Because here is what i found this info that's why i am asking

Powered Devices labeled as “compliant” fulfill IEEE’s strict requirements of
supporting both Mode A and Mode B power modes. 802.3af/at compatible Powered Devices on the other hand, usually only have the ability to provide power using Mode B.

Power pin outs for compatible powered devices are vendor-specific.
While 802.3af/at compatible powered devices can operate with compliant power sourcing equipment, there is no guarantee. If you find yourself in the market for an 802.3af/at compatible devices, ensure to check the product’s data sheet or contact your vendor to ensure that your prospective device will be compatible with your existing Power Sourcing Equipment.

Please make a note that compliant Power Sourcing Equipment can either support Mode A or Mode B, but IEEE doesn’t require compliant devices to support both power modes. Power Sourcing Equipment can essentially support one mode and still be considered compliant.
 
Understood.
From Wikipedia ==>> Power over Ethernet:

You don't select the mode, the PSE, and not the PD, decides whether power mode A or B shall be used.
Your only responsibility is to insure that both the PSE and the PD comply with 802.3af/at.
 
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