Well-Known Port List; Multinat Setup - Draytek Vigor2500V Manual

5.7 Well-known Port Number List
This page provides some well-known port numbers for your reference.
5.8 Multi-NAT Setup
The NAT, Network Address Translation establishes a many-to-one
relationship from your private IP address to your single public IP address. In
the most common type of router usage, the user uses the NAT facility of the
router to utilize the broadband access. i.e. Your family members can have
their own computer or laptop for Internet access but you just subscribe one
public IP address. Every computer or laptop receives a private IP address
from Vigor router. The NAT provides essential security to your network
clients because their private address is hidden from the outside world and
can not be reached directly, unless they are authorized to be contacted by
opening up ports/protocols.
NAT
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