Setting IP Precedence(TOS) on UDP traffic

rjsousa has asked for the wisdom of the Perl Monks concerning the following question:

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Re: Setting IP Precedence(TOS) on UDP traffic by rob_au (Abbot) on Jan 06, 2003 at 14:11 UTC
To do this you will need to construct the packet manually - The XS portion of the `Socket` module does not define the `SO_PRIORITY` macro which is used to set the protocol-defined priority for packets sent on a socket. The existing modules NetPacket and Net::RawIP may be of use in constructing UDP packets - Alternatively, an example of UDP packet construction from raw values using the `pack` function can be found in the Net::DHCPClient module. `perl -le 'print+unpack("N",pack("B32","00000000000000000000001000010000"))'`	[reply] [d/l] [select]
Re: Setting IP Precedence(TOS) on UDP traffic by pg (Canon) on Jan 06, 2003 at 15:51 UTC
At the same time, you may want to look into Net::Pcap. Pcap is a widely used c library for low level packet capture, and it is system independent. This can help you to deal with inbound packets in your application.	[reply]
Re: Re: Setting IP Precedence(TOS) on UDP traffic by rob_au (Abbot) on Jan 07, 2003 at 05:09 UTC
I quite like the pcap library, and in turn the Net::Pcap module. I thus thought it pertinent to add that Net::RawIP also incorporates an interface to pcap, specifically Net::RawIP::libpcap - This interface provides all the same functions as Net::Pcap and provides a capture mechanism to pair with Net::RawIP's packet building methods. `perl -le 'print+unpack("N",pack("B32","00000000000000000000001000010001"))'`	[reply]