nmap -sT -Pn 10.208.16.1

Nmap scan report for 10.208.16.1

Host is up (0.000015s latency).

Not shown: 991 filtered ports

PORT STATE SERVICE

25/tcp open smtp

110/tcp open pop3

119/tcp open nntp

143/tcp open imap

465/tcp open smtps

563/tcp open snews

587/tcp open submission

993/tcp open imaps

995/tcp open pop3s

//------------------------------

nmap -sT -Pn 172.18.2.206

Nmap scan report for 172.18.2.206

Host is up (0.00015s latency).

Not shown: 991 filtered ports

PORT STATE SERVICE

25/tcp open smtp

110/tcp open pop3

119/tcp open nntp

143/tcp open imap

465/tcp open smtps

563/tcp open snews

587/tcp open submission

993/tcp open imaps

995/tcp open pop3s