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Messaging Over IPv6 Headers
elias miles writes "A guy from the Swiss Unix Users Group made a cool utility that lets you chat over IPv6 packet headers. Not useful, but it's a nice hack.
Read the article and download joe 6 pack."
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"sonar"
From the description of the Debian package:
Description: console chat via ICMP (ping) echo-request packets sonar implements a peer to peer chat using ICMP (ping) echo-request packets, which means nearly stealth communication between two hosts without a central server.
It has an ncurses-based interface with basic support for multiple windows and chats with different peers. It is a reference implementation for the u23 project of the Chaos Computer Club Cologne (http://koeln.ccc.de)
So many half-truths, so little time...
Point 1 re 'Cisco sucks at IPv6' - do you have any data to back this up? Cisco seem to be doing fine with IPv6 deployments so I don't believe this is a real issue. More recent Cisco routers (7600, 10000, 12000 series) are hardware-based and will do IPv6 in hardware. Those that are software-based will forward IPv6 exactly like the other non-IPv4 protocols they have supported for years (DECnet, SNA, etc) - Cisco started out with multiprotocol routing not just IP. I'd be surprised if there is a big difference in performance - certainly there'll be more memory references with IPv6 addresses, but the IPv6 header (less the addresses) is shorter and simpler than the IPv4 header, so software-based routers may actually go faster on IPv6. Hardware-based routers should go at wire speed, basically.
Point 2 - there are already 1 billion cell phones in the world, and perhaps 30% of those are already IP-enabled. If you add in VoIP phones at home, and the myriad of new devices such as TiVOs, you can easily see how a mere 4 billion addresses is not enough - remember that India and China alone have 2 billion people. NAT is a hack that prevents simple deployment of more complex applications that aren't merely client to server - P2P apps work much more easily without NAT.
Point 3 - routing tables too large. Routing tables won't grow in size as you imply - if anything they are smaller for the true core routers, since IPv6 was designed to scale better using CIDR-like techniques for route aggregation, i.e. only a short prefix is stored and fewer prefixes should be needed. Your proposal for using the Ethernet-style MAC address doesn't work for ADSL, leased lines, and many other non-Ethernet media.
Point 4 - this is true for MTU-sized packets, but of course the host can send larger packets (frequently 1500 bytes or so), reducing this overhead. A 1 to 3 % overhead doesn't sound like much given IPv6's other advantages.
The fact that IPv6 allows stupid hacks like this is irrelevant. IPv6 is going to happen, it's just a question of time - my ADSL ISP already offers IPv6 as a checkbox option at no extra cost.