That's the way most extenders work. It uses the last three bytes of the device's MAC address and the first 3 bytes of the extender's MAC address. However, on my extender, the first bytes is changed to something else. I haven't figured that out yet. There is more information here:

https://www.reddit.com/r/HomeNetworking/comments/4huzzp/tplink_tlwa854re_wifi_extender_changes_client/?st=iuy0y1sp&sh=71b2d56e

its not supposed to do that, ive had the same problem on the WA855RE (v1.0 US), first of all i assigned the repeaters MAC address to its own ip

once connected to the main router the repeater got a different IP address then i personally assigned, the MAC of the repeater didnt match the label on the back or in the status page of the repeater

then i assigned the repeater its true mac and then it bound to the ip address i gave it but for no reason it just started messing up the MAC addresses in the whole network making DHCP useless
in repeater mode with DHCP disabled, it should forward the original MAC address and not modify this so it uses assigned ip addresses of the main router

because this breaks all functions of a repeater, devices that normal require a static IP become lost, unreachable (printers, NAS, smart switches) and also messes up parental control functions because your kid's tablet, computer or phone dont match the MAC that has the ip assigned for parental control


so i went back to the store to return my repeater and they exchanged it for model WA860RE (us v1.0) and this model is not affected by this bug
before i owned the model WA850RE (ES v1.20) spanish version and this one also was not affected by this bug

all models that uses the new firmware with the blue interface management page seem to be affected

also another bug is that no matter if you turn on/off the dhcp of the repeater
the repeater ignores this setting and gives an ip between 192.168.x.100 and 192.168.x.199 even if you set it to range 150 to 200 it will keep the range 100 to 199

Hi
it's not a bug.
850 works in proxy mode and this mode will change the devices' mac into a virtual one,all the first 24bits are the same, the latter 24bits of each client’s virtual MAC address are exactly the client’s real MAC address.
check this and you'll understand: http://www.tp-link.com/en/faq-927.html
if the mac do not change,then it works in WDS mode,but proxy mode is better than WDS mode to avoid many security problems.

about the mac on label,it is the mac on WAN port which you can see on router's dhcp page,the LAN mac should plus or minus 1 ( I may have mistaken their relationship but it's to say repeater has two mac,one to connect to router and one to devices)
if you want do do all the settings you mentioned,just fill the virtual mac address and real mac also.
can you understand me? it is to say,when your device connect to the router directly,dhcp page shows the real mac,when your device connect to repeater,the dhcp page on router shows the virtual mac.And the repeater won't assigned an IP(after you've configure it) , all the IPs are assigned by router.

For your infomation.

regards
zep

about the mac on label,it is the mac on WAN port which you can see on router's dhcp page,the LAN mac should plus or minus 1
if you want do do all the settings you mentioned,just fill the virtual mac address and real mac also.
can you understand me? it is to say,when your device connect to the router directly,dhcp page shows the real mac,when your device connect to repeater,the dhcp page on router shows the virtual mac.

QAQ wrote

Hi
it's not a bug.
850 works in proxy mode and this mode will change the devices' mac into a virtual one,all the first 24bits are the same, the latter 24bits of each client’s virtual MAC address are exactly the client’s real MAC address.
check this and you'll understand: http://www.tp-link.com/en/faq-927.html
if the mac do not change,then it works in WDS mode,but proxy mode is better than WDS mode to avoid many security problems.

about the mac on label,it is the mac on WAN port which you can see on router's dhcp page,the LAN mac should plus or minus 1 ( I may have mistaken their relationship but it's to say repeater has two mac,one to connect to router and one to devices)
if you want do do all the settings you mentioned,just fill the virtual mac address and real mac also.
can you understand me? it is to say,when your device connect to the router directly,dhcp page shows the real mac,when your device connect to repeater,the dhcp page on router shows the virtual mac.And the repeater won't assigned an IP(after you've configure it) , all the IPs are assigned by router.

For your infomation.

regards
zep

then its still a bug because i selected "Universal Mode" (WA855RE US/v1.0) also it doesnt explain why it ignores my DHCP settings (auto/off/on)
no matter what i choose the repeater start giving ip addresses between 192.168.x.100 and 192.168.x.199 (my main router is set only to give between 200 and 250 because all other addresses are pre-configured to their mac)
if i set DHCP Enable on the repeater and change the value for range between 200 and 250 its handing out between 100-199
if i set to auto or off it should take dchp from my main router that is set between 200 and 250 but keeps handing ip addresses out between 100-199

then this problem did not occur on my other repeater that was also running in "Universal Mode" (WA850RE ES/v1.20)
and the faulty one i exchanged for model (WA860RE US/v1.0) is also running like it should in "Universal Mode"

also forcing people into WDS mode, there is a line between safety and functionality
it breaks my wireless printer, smartplugs, nas, and parental controls and forwarded ports. since this is a private network WDS is not needed here
and also locks up my main router for some reason after a few hours

about the MAC address on the label,on all my tp-link products (main router wr940n and 2 repeaters wa860re & wa850re) the mac on the label is the wireless mac
and it didnt even match the LAN port on the repeater either, infact didnt match anything that was written on the label

regards,

J3rry.

QAQ , thank you for explaining

O m g thank you so much!! Like ive been googleing n googling & everyone is struggling w this bug & asking what we can do but nobody has actially named some extenders that dont have the bug!! Im ordering the proper 1 now!