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Open ports on LAN-side of Arris T1682G

New Poster

Open ports on LAN-side of Arris T1682G

A LAN-side scan of my Arris T1682G shows ten open or filtered ports.  Should there be this many?  Anyone have insight into what the ports > 443 are?  Nmap results below.


nmap -p-

Starting Nmap 7.70 ( https://nmap.org ) at 2018-05-14 16:33 PDT

Nmap scan report for

Host is up (0.0020s latency).

Not shown: 65525 closed ports


22/tcp    filtered ssh

23/tcp    filtered telnet

53/tcp    open     domain

80/tcp    open     http

443/tcp   open     https

2601/tcp  open     zebra

7547/tcp  filtered cwmp

49152/tcp open     unknown

51515/tcp open     unknown

58081/tcp open     unknown

New Poster

Re: Open ports on LAN-side of Arris T1682G

Look like port forwarding setup for a game console or some other device that requires specific ports to be open.

Problem Solver

Re: Open ports on LAN-side of Arris T1682G

Zebra (TCP 2601) is an older networking protocol that tells devices where to go on yout network. TCP 7547 is the CWMP (CPE WAN Management Protocol) , which is an autoconfiguration protocol for remote devices via a WAN link. Those two are most likely from Comcast, i.e. the gateway.. 


The last three are dynamic TCP ports, which I suspect are from Windows computers on your network. 


SInce they're on the LAN side, and not the WAN, they're internal to your network, and quite normal, so I wouldn't be worried about them. 

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