10-03-2013
Question about blocking incomming traffic
Hello,
Like many others, I have continued to get attempts to connect to my local net router from the Asia Pacific Network Information Centre and from RIPE Network Coordination Centre, Amsterdam. I would say that 90% of attempted connections come from these two locations. The originating IP address is usually not registered in ARIN, so there is no specific IP range I can block. It is probably pointless to block individual IP addresses, so I have been thinking about other methods.
I began wondering why I should allow any inbound connections, meaning connection requests that originate off of my local net. After thinking about this, I realize that I don't fully understand these protocols as well as I should. Can someone explain whether or not I should block all incoming connections (I am not running any kind of service that would need incoming connections, ftp, sshd, etc). If I can't block all of them, which ones should I continue to allow? What would such a firewall rule look like, etc?
Thanks for any assistance that you can provide.
LMHmedchem
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LEARN ABOUT DEBIAN
vanessa_socket_pipe
VANESSA_SOCKET_PIPE(1) General Commands Manual VANESSA_SOCKET_PIPE(1)
NAME
vanessa_socket_pipe - Trivial TCP/IP pipe based on libvanessa_socket
SYNOPSIS
vanessa_socket_pipe [options]
DESCRIPTION
A TCP/IP pipe is a user space programme that listens for TCP/IP connections on port on the local host and when a client connects makes a
connection to a TCP port, possibly on another host. Once both connections are established data sent on one connection is relayed to the
other, hence forming a bi-directional pipe.
Uses include enabling connections to specific ports on hosts behind a packet filter.
This code is intended primarily as an example of how many of the features of libvanessa_socket work.
OPTIONS
-c|--connection_limit:
Maximum number of connections to accept simultaneously. A value of zero sets no limit on the number of simultaneous connections.
(default 0)
-d|--debug:
Turn on verbose debuging to stderr.
-h|--help:
Display this message.
-L|--listen_port:
Port to listen on. (mandatory)
-l|--listen_host:
Address to listen on. May be a hostname or an IP address. If not defined then listen on all local addresses.
-n|--no_lookup:
Turn off lookup of hostnames and portnames. That is, hosts must be given as IP addresses and ports must be given as numbers.
-O|--outgoing_port:
Define a port to connect to. If not specified -l|--listen_port will be used.
-o|--outgoing_host:
Define host to connect to. May be a hostname or an IP address. (mandatory)
-q|--quiet:
Only log errors. Overriden by -d|--debug.
-t|--timeout:
Idle timeout in seconds. Value of zero sets infinite timeout. (default 1800)
Notes: Default value for binary flags is off.
-L|--listen_port and -o|--outgoing_host must be defined.
AUTHOR
Simon Horman <horms@verge.net.au>
12th February 2001 VANESSA_SOCKET_PIPE(1)