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Comment Re:There is a reason send/return pathes are not... (Score 1) 347

PEIP and Fair Service require implementation on a cooperating network of routers in which case what is encoded in each router only requires space proportional to the number of hops to the router times the number of ancestor routers of the router.

As stated in :

The longest paths in the Internet are currently about 25 hops. The average is actually much less. The routers that forward packets are typically connected to no more than 16 other routers. Therefore a typicalhop should take no more than 4 bits. This gives a total of about 16 bytes for the longest paths in IPv4 (including the 4 byte explicit address) and 28 bytes in IPv6 (where the explicit address is 16 bytes).

Of course, in packets with an extra path, the expense could be twice as high. However, as noted above, these packets make up a small fraction of the traffic in the Internet. To give an idea of the value of the bandwidth being used, it is relevant to mention that the smallest possible IPv6 header is 40 bytes, whereas the smallest possible IPv4 header is 20 bytes. Most IPv4 headers are actually the minumum length. Anyone who wants to move from IPv4 to IPv6 therefore must be willing to pay 20 bytes per packet.

The time it takes a router to add its data to the path is a small constant. This should pose not a serious problem. If expanding a packet is problematic for specific routers, it would be possible to pre-allocate space. A more serious problem is that this extra data might require fragmentation. For non-attack traffic this does not seem like a major problem. TCP traffic, which comprises most of the traffic in the Internet, avoids this problem by using non-fragmentable packets to find a Path MTU. Attack traffic is discussed below.

A reasonable question is what maximum size of paths must be supported. Both IPv4 and IPv6 limit paths to 255 hops. As noted above, this is far more than any real paths. Of course, legitimate paths must not be cut off since that prevents source tracing. On the other hand, there are good reasons to limit the length to the maximum realistic path length. Something in the range of 30 hops or 16 bytes (for IPv4) seems like a reasonable limit.

Comment Re: Ineffective (Score 1) 347

Although Don Cohen's PEIP Fair Service approach is effective for the case spoofed packets it is equally effective for the case of legitimate packets.

As I state in :

PEIP and Fair Service are not overwhelmed by the âoesheer number of connectionsâ because what matters is the set of router paths leading to each host. Think of the host being targeted. Now consider the spanning tree of the graph of routers that are involved in routing packets to that host. If every router in that spanning tree has implemented Fair Service then most paths will be providing unhindered service. Even the most prolific attack can only compromise a tiny set of the router paths and even then if Fair Service is implemented all the way back to each source host, even the initial packets from each zombie source client will only receive Fair Service.

I have asked Don Cohen to reply here in more detail. Letâ(TM)s see what he has to say.

Submission + - A solution for DDOS packet flooding attacks (

dgallard writes: On October 21, 2016, a DDOS attack crippled access to major Web sites including Amazon and Netflix.

PEIP (Path Enhanced IP) extends the IP protocol to enable determining the router path of packets sent to a target host. Currently, there is no information to indicate which routers a packet traversed on its way to a destination (DDOS target) enabling use of forged source IP addresses to attack the target via packet flooding.

PEIP changes all that. Rather than attempting to prevent attack packets, instead, PEIP provides a way to rate-limit all packets based on their router path to a destination. In this way, DDOS attacks can be thwarted be simply only allowing them a limited amount of bandwith.

Comment usual slashdot flame wars (Score 1) 225

There was one funny post about the lost screw comng back.

The other *hundreds* of posts were idiotic flame wars about measurement units and what not.

A more interesting discussion would be to wonder how incidents like this, which per the article are common, would impact the longevity of the space station and other proposed long-term dwellings in orbit.

Just wondering.

Comment No need for 2x (was: Re:Incompetent IT) (Score 1) 239

An anonymous coward stated:

> First off you need a minimum of 2x the floor space in a min 2 different geographic locations.
> Second you need a min 2x the hardware at both locations. blah blah blah
> You need 2 x the number of blah blah blah
> Blah blah blah

Today you can do DR (Disaster Recovery) in AWS or other cloud infrastructure without needing 2x blah blah blah.

You do need 2x for *just* the database that stores truth and keeps it redundant sychronously or, in this case, near synchronous is probably good enough (OK lose a few hundred or even thousand transactions I would guess, just NOT OK to lose the entire system for a day. Jeeeesh.).

Almost all other systems can stay quiescent and not used actual cycles or energy until needed for recovery.

-- Dennis Allard

Comment Re: Hoax (Score 1) 1105

ScentCone stated:

> Those would be the evil rich people who pay almost all of the country's income taxes?
> Yeah, Socialism - where success is indeed punished, and the stuff that's taken is given
> to other people. That's socialism for everybody, because it's socialism doing what it likes
> to do: taking from the most productive/successful, and giving to the least. Half the country
> pays no income taxes at all (or pay's negative income taxes, getting "refunds" and cash
> credits on taxes they don't even pay), and the vast majority of the income taxes that are
> paid are paid by a small portion of the other half.

The vast majority of the income and wealth goes to the top 10% and, actually, to the top 1%.

And their wealth comes form what they own not what they do. Gates owns/owned one third
of Microsoft stock. Yes, he's smart and founded a successful company but his total fortune
was based on ownership of stock, the value of which was created by workers at Microsoft.

Albert Einstein was a socialist.

Germany is a social democracy, has a standard of living higher than the United States, is a
net exporting manufacturing economy, and has free tuition for all strudents at all levels.

All of the above contradict your Libertarian Fundamentalist religious-like views.

BTW, I am a socialist and I am for *more* people owning things, not fewer. This Libertarian
Fundamentalist clap trap about socialists wanting the gov'ment to own everything is B.S.

We should have natioanlized banks that enable all current renters to purchase their units
and own them instead of paying their landlords mortgage.

See the above link for more argumentation along those lines.

Dennis Allard
Santa Monica
February 15, 2016

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Comment Re:10 years (Score 1) 279

lisp is so elegant it has made all other languages look silly since 1959

javascript is strongly influenced by lisp

scala is adding lisp to a fixed up version of java that runs in a JVM and code is way less ugly to write

i hope people will discover ap5 ( an extension to lisp that uses first order logic to express conditions and define n-ary relations

Comment Re:The fuss over Uber (Score 1) 385

So now we are going to witness the usual repartee, not to mention bull shit, of exchanges between the Libertarian Fundamentalists and reasonable people with absolutely no one changing their mind. I personally like Uber (especially the fantastic job they did no their app GUI), but also, being one of the "reasonable people", will side with those who favor government regulation and things like higher wages for working people, including Uber drivers. Libertarian fundamentalists do not believe one can provide regulations that result in better working conditions and higher wages without somehow reducing "freedom" (the freedom for those who own to acquire more wealth) or without reducing efficiency of the economy (part of the bull shit aspect of their so-called theory).

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