Connectivity
Manual configuration
Use these settings to manually configure DC++ for incoming connections. If unsure about these settings,
you may want to follow the Manual connection setup guide.
While some settings as various Ports are shared, the rest are grouped making possible to individually
set and fine tune connectivity for IPv4 and IPv6 protocols. Settings on this pane are unavailabe and ignored
when Automatic connectivity setup is enabled.
Note that IPv6 support is currently in experimental state and DC++ might not able to connect to all kinds
of DC clients using the IPv6 protocol.
Before changing these make sure you are familiar with the meaning of each connection mode and with the differences between active and passive mode and their effect on your ability to
search and download from users of the DC network.
Manual incoming connection settings for both IPv4 and IPv6 protocols
- Ports
These settings specify the communication ports DC++ listens on for incoming connections.
Generally you don't need to add specific ports unless you configured your port forwarding settings
manually. If port settings are left blank, DC++ will let the operating system generate a random
port number. Port values are ignored when
Automatic connectivity setup is enabled.
- Transfer port (TCP)
- This is the port that DC++ listens on for
incoming connections from other peers. If this port is incorrectly forwarded, you won't be
able to download.
- Encrypted transfer port (TCP)
- This is the port that DC++ listens on for
incoming TLS (encrypted) connections from other peers. If
this port is incorrectly forwarded, you won't be able to search nor to download on
encrypted ADC hubs. Note that this port value should be different than the one used for
transfers (TCP).
- Search port (UDP)
- This is the port that DC++ listens on for
incoming search results. If this port is incorrectly forwarded, you won't be able to
receive search results.
Individual settings for IPv4 and IPv6 protocols
The following incoming connection settings grouped to be able to
do a separate setup for the two available IP protocols.
- Active mode (I have no router / I have configured my router)
-
Select this mode if you are directly connected to the Internet (no router) or if you are
willing to manually configure port forwarding rules in your router. Use this mode only if the
automatic configuration (via NAT-PMP / UPnP) is not an option for you. For more information,
refer to the Manual port forwarding guide.
- Active mode (let DC++ configure my router with NAT-PMP / UPnP)
-
Select this mode if you are behind a router that supports standard port forwarding methods such
as NAT-PMP or UPnP. Most routers do support them but they often have to be explicitly enabled
from the router's configuration page. Thanks to automatic port mapping methods, DC++ is able to
open the ports it needs and obtain your external IP address as well. For more information, see
What is NAT-PMP / UPnP?.
- Passive mode (last resort - has serious limitations)
-
Select this mode if you can't get active mode to work. In this mode, DC++ will not try to
listen for inbound connections; it will only initiate outbound ones. This mode carries some
serious limitations:
- only 5 results per user will be returned in response to searches.
- you may not be able to download / receive search results from passive users.
- you may not be able to fully enjoy certain hubs (because of their regulations).
Note that DC++ tries NAT Traversal on ADC hubs to allow passive users to connect with each other.
- Disable connectivity
-
Select this mode if you do not wish to have the specified protocol active.
- External / WAN IP address
-
These fields specify your external IP addresses for the specified protocol.
Note: most hubs are able to determine your external IPs and forward it to your DC++, making
a manual configuration of this field unnecessary. If your computer is directly connected to
the internet, your internal and external IP will be the same and can easily be automatically
detected. Fill these boxes only if you need to override said auto-detection.
Ordinarily, only users behind a router (NAT device) need to fill in this boxes.
If you put a DNS name here, DC++ will try to resolve it into an IP address before use.
For additional information like how to determine your external IP
address, follow the Manual connection setup guide.
- Don't allow hubs/NAT-PMP/UPnP to override
-
Enable this to always use the IP address in "External / WAN IP", and not let either NAT-PMP,
UPnP nor connected hubs change it. If unsure, leave this setting disabled.
- Preferred port mapping interface
-
DC++ has several interfaces available it can use to try to automatically map the ports it
requires on the router:
- NAT-PMP: A lightweight protocol that is not widely used by generic routers; but
open-source firmwares generally implement it.
- MiniUPnP: An open-source UPnP library.
The interface selected here will be tried first; other available interfaces will then be tried
if the preferred port mapping interface were to fail.
- Bind Address
-
This setting allows binding DC++ network connections of the specified protocol to a specific network
adapter by its IP address. Useful when you have more than one physical or virtual network adapter installed and
you want to assign a specfic device for all the network traffic generated for a certain IP protocol
by DC++.
If this setting is set to 'Default' it means that DC++ is relying on the operating
system to find the best adapter. In case of the adapter offered by the operating system does
not suit you, you can override it here by selecting the required adapter.
If binding with the selected adapter fails, it will do so silently and the 'Default' setting
(INADDR_ANY) will be used instead.