Free tolerant routing system software for linux

BitWise Routing Server allows multiple PCs behind a router to make direct connections.

The BitWise Routing Server allows you to accept BitWise connections to multiple computers behind a router. Typically, using a router, you would set up port forwarding on BitWises client port (4137), and specify a single destination IP. This is fine until multiple users behind a router all need to accept incoming connections.

As shown by the picture at right, the Routing Server allows individual users to register themselves with the Routing Server, and then the Routing Server accepts all incoming connections and directs those connections to the appropriate user.

The Routing Server requires that your physical router support port forwarding with a way to specify different external and internal ports (this is sometimes labeled "UPnP" by many common home routers).

The Routing Server has several options allowing you to customize the Routing Server for your environment. Many of the options are self-explanatory. The two that are not are Listen on Port and IP filtering. IP filtering is explained in the next section.

The BitWise Routing Server listens on a different port than the BitWise IM client. This allows the Routing Server and the IM client to be run on the same computer without causing conflicts. You will want to set up your router (more detail in a later step) to shift the port of the incoming connections from 4137 to another port. It doesnt particularly matter which port you want to use, as long as it is not a port used by another program. The default port is 4200.

Depending on the complexity of the network, it may be desirable to filter the IP addresses that are allowed to register with the Routing Server. This can be done in the preferences. One very likely scenario would be limiting registrations to the 192.168.1.x IP addresses (192.168 is reserved for local networks). When specifying an IP as the comparison address, you can use any valid IP numbers for wildcards.

In the case shown here, the Routing Server will limit connections to computers having IP addresses of 192.168.1.x. Any number, 0 through 255, could be placed for x in the Routing Server preferences.

If you are not familiar with IP address classes and IP filtering, it will usually be safe to leave Any selected.

Setting up the physical router

The picture at right was taken from a Linksys router, other routers will have a similar capability, although it may be layed out differently. On some routers, the advanced port forwarding options are mistakingly labeled UPnP.

The router setup shows that we are accepting connections on port 4137 and then sending them inside the network on port 4200 (the default port). Enter the IP address of the machine on the network running the Routing Server, and make sure that the rule is enabled. You will want to enter a rule for both TCP and UDP (UDP is used only for voice).

Please consult your router manual for more detailed instructions about how to set up port forwarding on your specific model.

Configuring BitWise to use the Routing Server

In order for you to enjoy the connectivity benefits of the Routing Server, you will need to register with the Routing Server when you log in to BitWise. Prior to logging in to BitWise, click the Setup button next to the Connect button to open the BitWise Setup. There is an area to enter an address for the Routing Server, and to specify what port to use. The port must be the same as the port used above (4200 is the default).

Upon connecting to BitWise, you will be registered with the Routing Server. If you could not be registered, an error message will be displayed. Double-check that the correct address was entered in the Setup.

Registration with the Routing Server

Upon successfully registering with the Routing Server, the Routing Server will display the user name and the IP address of the registration. If you want to unregister a user, click on the username, and then click Unregister. Incoming connections will no longer be forwarded to the specified computer.

It is worth pointing out two things here. First, if you later log in from a different computer, and that computer is also set to use the Routing Server, you will be re-registered with your new IP address. Second, if you are unregistered, or move to another computer but are not set up to use the Routing Server, you will not be able to benefit from the services of the Routing Server.
By default, the Routing Server saves the registered user list when it is closed down.

Using the Routing Server

Assuming that everything is set up correctly, everyone that registers with the Routing Server when they log in to BitWise will be able to enjoy significantly increased connectivity with other BitWise users. As incoming connections are established, you will see the connections listed in the right pane of the Routing Server window. The IP address and the time of the connection is also displayed, and the connection is later marked when it is disconnected.

The disconnected/closed connections may be cleaned from the list at any time using the Clean List button. Only active connections will be left displayed.

Ad-hoc Wireless Distribution Service (AWDS) is a Layer 2 routing protocol for wireless mesh networks. The project provides transparent Ethernet-like access to all participating nodes, thus easily allowing the employment of different higher level protocols like IP (with DHCP), IPv6, AppleTalk, ...

A Linux implementation of AWDS can be downloaded from our download section. Ports to other platforms are highly appreciated!

Internet Registry Routing Daemon (IRRd) is a freely available, stand-alone Internet Routing Registry database server. IRRd supports the RPSL and RPSLng Routing Policy Specification Language standards.

The IRRd package includes all required IRR support services, including: automated near real-time mirroring of other IRR databases, update syntax checking, authentication/security, and notification.

Routing incoming ppp0 is a netfilter firewall.

Sample:

#!/bin/bash

# Load required modules
insmod ip_tables
insmod ip_conntrack
insmod iptable_nat
insmod ipt_MASQUERADE

# Then flush all rules
iptables -F
iptables -t nat -F

# In the NAT table (-t nat), Append a rule (-A) after routing
# (POSTROUTING) for all packets going out ppp0 (-o ppp0) which says to
# MASQUERADE the connection (-j MASQUERADE).

#iptables -t nat -A POSTROUTING -o ppp0 -j MASQUERADE

# Below means route 192.168.1.x
iptables -t nat -A POSTROUTING -d ! 192.168.1.0/24 -j MASQUERADE

iptables -A FORWARD -s 192.168.1.0/24 -j ACCEPT
iptables -A FORWARD -d 192.168.1.0/24 -j ACCEPT
iptables -A FORWARD -s ! 192.168.1.0/24 -j DROP

# Disallow NEW and INVALID incoming or forwarded packets from ppp0.
#iptables -A INPUT -i ppp0 -m state --state NEW,INVALID -j DROP
#iptables -A FORWARD -i ppp0 -m state --state NEW,INVALID -j DROP

# port 113 is evil ;)
iptables -A INPUT --protocol udp --source-port 113 -j DROP
iptables -A INPUT --protocol udp --destination-port 113 -j DROP

# Turn on IP forwarding
echo 1 > /proc/sys/net/ipv4/ip_forward

#iptables -A INPUT --protocol udp --source-port 113 -j DROP

# Route incoming ppp0 at port 80, to 192.168.1.18:80
iptables -A PREROUTING -t nat -p tcp -i ppp0 --dport 80 -j DNAT --to 192.168.1.18:80

# Route incoming ppp0 at port 21, to 192.168.1.18:21
iptables -A PREROUTING -t nat -p tcp -i ppp0 --dport 21 -j DNAT --to 192.168.1.18:21

Balsa project is an asynchronous circuit synthesis system. Balsa is built around the Handshake Circuits methology, and it can generate gate level netlists from high-level descriptions in the Balsa language.

Both dual-rail (QDI) and single-rail (bundled data) circuits can be generated.