[SOLVED] reserved IP that I never added

[Emiliortega]

I've entered to my router and in the client's list of my router I see all devices connected to the router and it has a part where you can add a reserved IP for certain client, and it appears a client there that I never added with name unknown

There I posted the picture with the router and that client that I never added, I'm not sure what that is or why it appears there, I can delete it too but I'm not sure if it's something related to the router or what, so I hope someone can know something about it,
thanks in advanced

 

[SamirD]

Search that mac address here and see who makes the nic--it might just be something like a smart tv that you forgot you put in the router...not like I've done that or anything...🤣

 

[Emiliortega]

Search that mac address here and see who makes the nic--it might just be something like a smart tv that you forgot you put in the router...not like I've done that or anything...🤣

I looked the mac up and it belongs to ARRIS Group, Inc.
haha I'd like that it would be a tv or something but I have good memory and I've never added an ip as reserved so that's what worries me... and Im the only one with access to the router

 

[SamirD]

Who makes your cable modem and router?

 

[DeauteratedDog]

The Arris OUI suggests that it is a cable modem/router/mesh router or something like that.

 

[SamirD]

The Arris OUI suggests that it is a cable modem/router/mesh router or something like that.

That was my thinking too--unless the owner doesn't have anything branded arris...

 

[Emiliortega]

Who makes your cable modem and router?

I don't understand very well the question, are you asking me for my ISP ? if that so the company is VTR (https://vtr.com/ ) they provide me internet and TV

 

[Emiliortega]

The Arris OUI suggests that it is a cable modem/router/mesh router or something like that.

Could you tell me what does "OUI" means ? and the weird thing is that I only have the router Arris and apart from the router is a DECODER FOR CABLE TELEVISION model dcx3520 and it belongs to arris. The mac that appeared as "reserved" from that "unknown" device that I didn't add is "00:00:CA:01:02:03 " but I looked the stickers in the TV decoder and it has 5 things; UA, HOST SN, eSTB MAC, DOCSIS MAC and HUID, but none of them has the same numbers as the MAC of the element "unknown" found in my router configurations

 

[DeauteratedDog]

OUI = Organizationally Unique Identifier. The 1st half of a MAC address; it identifies the manufacturer of the equipment.
00:00:CA indicates Arris.

 

[Emiliortega]

OUI = Organizationally Unique Identifier. The 1st half of a MAC address; it identifies the manufacturer of the equipment.
00:00:CA indicates Arris.

thanks, and do you have any idea what that could be ? I did ping to its ip and I get 4 packages sent, 3 received and 1 lost

 

[DeauteratedDog]

If it answers a ping, run a port scanner against it - nmap or something like that.

You can also just try hitting it with a browser and see if it answers on port 80 (http) or 443 (https).

 

[Emiliortega]

If it answers a ping, run a port scanner against it - nmap or something like that.

You can also just try hitting it with a browser and see if it answers on port 80 (http) or 443 (https).

the unknow device appears in my network with a software that I installed in windows but it doesn't show any ports (Im not sure what it means)... and my computer shows open ports but I think they're the typical ones

 

[DeauteratedDog]

If no ports on the device are open, then it will be very hard to determine what it is.

Your best bet may be to black-list it (block its MAC address) and see if anything around the house stops working.

What port scanner software did you use? Here is a link to several: https://www.netadmintools.com/port-scanners/

 

[SamirD]

I don't understand very well the question, are you asking me for my ISP ? if that so the company is VTR (https://vtr.com/ ) they provide me internet and TV

No, not the isp--the manufacturer of your modem/router unit(s), which you've answered is arris--probably just a piece of your isp equipment and nothing to worry about.

 

[kanewolf]

Could you tell me what does "OUI" means ? and the weird thing is that I only have the router Arris and apart from the router is a DECODER FOR CABLE TELEVISION model dcx3520 and it belongs to arris. The mac that appeared as "reserved" from that "unknown" device that I didn't add is "00:00:CA:01:02:03 " but I looked the stickers in the TV decoder and it has 5 things; UA, HOST SN, eSTB MAC, DOCSIS MAC and HUID, but none of them has the same numbers as the MAC of the element "unknown" found in my router configurations

It is most likely your TV box. Many TV boxes use IP for on-demand programming and for the on-screen guide. There is probably a sticker on the bottom of the TV box which shows the MAC address.